report of the ices advisory reports/ices advice/2008/ices a… · dk-1553 copenhagen v denmark...

ICES ADVICE 2008 AVIS DU CIEM

Books 1- 10

Report of the ICES Advisory Committee 2008

Book 5 Celtic Sea and West of Scotland

International Council for the Exploration of the Sea Conseil International pour l’Exploration de la Mer

H.C. Andersens Boulevard 44-46 DK-1553 Copenhagen V Denmark Telephone (+45) 33 38 67 00 Telefax (+45) 33 93 42 15 www.ices.dk [email protected] Report of the ICES Advisory Committee, 2008. Books 1 - 10 December 2008 Recommended format for purposes of citation: ICES. 2008. Report of the ICES Advisory Committee 2008. ICES Advice, 2008. Book 5, 267, pp. For permission to reproduce material from this publication, please apply to the General Secretary.

ISBN 978-87-7482-051-2

BOOK 5 Section Page 5 CELTIC SEA AND WEST OF SCOTLAND......................................................................................................... 1

5.1 Ecosystem Overview...................................................................................................................................... 1

5.1.1. Ecosystem components .................................................................................................................. 1

5.2 The human impacts on the ecosystem ............................................................................................................ 9

5.2.1 Fishery effects on benthos and fish communities........................................................................... 9

5.3 Assessments and advice ............................................................................................................................... 13 5.3.1 Assessments and advice regarding protection of biota and habitats............................................. 13 5.3.2 Assessment and advice regarding fisheries .................................................................................. 13 5.3.3 Special requests............................................................................................................................ 36 5.3.3.1 EC request to review 2008 Celtic cod advice................................................................... 36

5.4 Stock summaries ....................................................................................................................................... 41 5.4.1 Cod in Division VIIa (Irish Sea) .................................................................................................. 41 5.4.2 Cod in Divisions VIIe-k (Celtic Sea Cod).................................................................................... 50 5.4.3 Haddock in Division VIIa (Irish Sea) .......................................................................................... 61 5.4.4 Haddock in Divisions VIIb-k ....................................................................................................... 66 5.4.5 Whiting in Division VIIa (Irish Sea)............................................................................................ 68 5.4.6 Whiting in Divisions VIIe-k......................................................................................................... 71 5.4.7 Plaice in Division VIIa (Irish Sea) ............................................................................................... 73 5.4.8 Celtic Sea Plaice (Divisions VIIf and g) ...................................................................................... 82 5.4.9 Plaice in Division VIIe (Western Channel).................................................................................. 91 5.4.10 Plaice Southwest of Ireland (Divisions VIIh-k) ........................................................................... 93 5.4.11 Plaice West of Ireland (Division VIIb,c)...................................................................................... 95 5.4.12 Sole in Division VIIa (Irish Sea).................................................................................................. 97 5.4.13 Sole in Division VIIf and g (Celtic Sea) .................................................................................... 106 5.4.14 Sole in Division VIIe (Western Channel) .................................................................................. 115 5.4.15 Irish Sea herring (Division VIIa) ............................................................................................... 127 5.4.16 Celtic Sea and Division VIIj herring.......................................................................................... 129 5.4.17 Herring in Divisions VIa South and VIIb,c................................................................................ 136 5.4.18 Sprat in Divisions VIId,e............................................................................................................ 138 5.4.19 Megrim (Lepidorhombus whiffiagonis) in Divisions VIIb-k and VIIIa,b,d ............................... 140 5.4.20 Anglerfish in Divisions VIIb-k and VIIIa,b,d (Lophius piscatorius and L. budegassa) ............ 141 5.4.21 Cod in Division VIa (West of Scotland) .................................................................................... 142 5.4.22 Cod in Division VIb (Rockall) ................................................................................................... 151 5.4.23 Haddock in Division VIa (West of Scotland) ............................................................................ 152 5.4.24 Haddock in Division VIb (Rockall) ........................................................................................... 161 5.4.25 Whiting in Division VIa (West of Scotland).............................................................................. 170 5.4.26 Whiting in Division VIb (Rockall)............................................................................................. 172 5.4.27 Saithe in Subarea VI (West of Scotland and Rockall) ............................................................... 173 5.4.28 Megrim in Subarea VI (West of Scotland and Rockall)............................................................. 174 5.4.29 Anglerfish in Division IIa (Norwegian Sea), Division IIIa (Kattegat and Skagerrak), Subarea IV

(North Sea), and Subarea VI (West of Scotland and Rockall) (Lophius piscatorius and L. budegassa)................................................................................................................................. 177

5.4.30 Herring in Division VIa North ................................................................................................... 185 5.4.31 Norway pout in Division VIa (West of Scotland) ...................................................................... 194 5.4.32 Sandeel in Division VIa ............................................................................................................. 196 5.4.33 Nephrops in Division VIa .......................................................................................................... 197

5.4.33.1 Nephrops in North Minch (FU 11) ............................................................................. 203 5.4.33.2 Nephrops in the South Minch (FU 12) ....................................................................... 207 5.4.33.3 Nephrops in the Firth of Clyde (FU 13) ..................................................................... 211

5.4.34 Nephrops in Division VII........................................................................................................... 215 5.4.34.1 Nephrops in Irish Sea East (FU14) ............................................................................. 221 5.4.34.2 Nephrops in Irish Sea West (FU 15) .......................................................................... 226 5.4.34.3 Nephrops on Porcupine Bank (FU 16) ....................................................................... 231 5.4.34.4 Nephrops on Aran Grounds (FU 17)........................................................................... 237 5.4.34.5 Nephrops off the southeastern and southwestern coasts of Ireland (FU 19) ............... 251 5.4.34.6 Nephrops in the Celtic sea (FU 20–22) ....................................................................... 246

5.4.35 Sole Southwest of Ireland (Division VIIh-k) ............................................................................. 251 5.4.36 Sole West of Ireland (Division VIIb,c) ...................................................................................... 253 5.4.37 Demersal elasmobranchs in the Celtic Sea and West of Scotland.............................................. 255

ICES Advice 2008, Book 5 1

5 CELTIC SEA AND WEST OF SCOTLAND 5.1 Ecosystem overview 5.1.1 Ecosystem components Bottom topography substrate and circulation The ‘Celtic Seas’ comprise the shelf area west of Scotland (ICES Subarea VIa), the Irish Sea (VIIa), west of Ireland (VIIb), as well as the Celtic Sea proper (VIIf-k) and western Channel (VIIe). Throughout this ecoregion the continental shelf is of variable width. The Celtic Sea south of Ireland is an extended shelf within which most of the area is shallower than 100 m. It is limited to the west by the slope of the Porcupine seabight and the Goban Spur. To the west of Ireland, the Porcupine Bank forms a large extension of the shelf limited to the west by the Rockall Trough. The transition between the Porcupine Bank and the trough is a steep and rocky slope along which reefs of deep-water corals occur. Further north to West of Scotland the slope of the Rockall Trough is closer to the coast line, particularly off NW Ireland, and the Hebrides. West of the shelf break is the Rockall Plateau with depths of less than 200 m. The shelf area itself contains mixed substrates, generally with soft sediments (sand and mud) in the west and tending to rockier pinnacle areas to the east. The Irish Sea is shallow (less than 100 m deep in most places) and largely sheltered from the winds and currents of the North Atlantic. The English Channel is a shallow (40–100 m) part of the continental shelf. Its hydrology is marked by a west to east general circulation disrupted by strong tidal current. To the west of the region there are several important seamounts, notably the Rosemary Bank, the Anton Dohrn seamount, and the Hebrides, which have soft sediments on top and rocky slopes. Water circulation on the shelf is strongly influenced by the poleward flowing ‘slope current’. This persists throughout the year north of Porcupine Bank, but is stronger in the summer. South of the bank, the current breaks down in the summer, when flow patterns become complex. Over the Porcupine Bank and the Rockall plateau, domes of cold water are associated with retentive circulation. On the shelf is also a weaker current flowing north from Brittany across the mouth of the channel (OSPAR, 2000; Young et al., 2004). Thermal stratification and tidal mixing generates the Irish coastal current which runs westwards in the Celtic Sea and northwards along the west coast of Ireland (Fernand et al., 2006). In the Irish Sea, an inshore coastal current carries water from the Celtic Sea and St. Georges’s Channel northwards through the North Channel, mixing with water from the outer Clyde. The main oceanographic front in the NE Atlantic region is the Irish Shelf Front that occurs to the south and west of Ireland (at ca. 11°W), and exists all year-round. This front marks the boundary between waters of the shelf (often mixed vertically by the tide) and offshore North Atlantic waters. The turbulence caused by the front introduces nutrients from deeper water to the surface where they promote the growth of phytoplankton, especially diatoms in spring, but also dinoflagellates especially where there is pronounced stratification. These are in turn fed on by cohorts of zooplankton and associated with these aggregations of fish (Reid et al., 2001). On the shelf, tidal mixing and thermo/saline fronts occur at several locations immediately to the west of Britain, including the Ushant Front in the English Channel, the Celtic Sea front at the southern entrance to the Irish Sea, and the Islay Front between Islay and the coast of Northern Ireland. The Islay Front persists throughout the winter, due to stratification of water masses of different salinity. Similarly, where tides are moderate, uneven bottom topography can have a considerable mixing effect, for example in the seas around the Hebrides. Physical and chemical oceanography Temperature/salinity The ICES Annual Ocean Climate Status Summary (IAOCSS) provides long-term time-series for temperature and salinity anomalies from the Rockall Trough situated west of Britain and Ireland dating back to 1975. Shorter data series are available for the western Irish shelf since 1999 (ICES, 2007). The Rockall Trough is an important pathway by which warmer North Atlantic surface waters reach the Norwegian Sea, where they are converted into cold dense overflow water as part of the thermohaline circulation in the North Atlantic. In 2006, the warm and saline conditions persisted in the upper ocean of the Rockall Trough, though salinity has been decreasing since a peak in 2003 (Figure 5.1.1). The notable decrease in mean salinity in 2006 was caused by the presence of fresher water between the Anton Dohrn Seamount (11°W) and the Rockall Bank (13°W); however, the shelf edge current (at 9°W) had persistently high salinities. Temperatures once again reached record levels, though most of the additional warming since 2005 was confined to the upper 400 m. Upper ocean temperatures (0–800 m) were 0.8°C and salinity 0.04, above the long-term mean (1975–2000).


Figure 5.1.1 Rockall Trough temperature and salinity anomalies for the upper ocean (0–800 m) of the northern

Rockall Trough. Average across section, seasonal cycle removed. Summer CTD measurements made along a section at 53°North on the western Irish shelf since 1999 show warmer conditions in 2003 and 2004, broadly consistent with other regions of the NW European shelf while cooler conditions were observed in 2001 and 2002. Salinity also exhibits strong interannual variability along this section, depending on the timing and magnitude of discharges both locally from Irish rivers and from rivers to the south of the section in the UK and France. Sea surface temperatures measured in coastal stations northwest of Ireland since the 1960s show a trend of sustained positive temperature anomalies from 1990 (Nolan and Lyons, 2006). Inshore waters off the west of Scotland have also continued to warm, consistent with open-ocean conditions. At Millport, where monitoring has been conducted since 1953, gradual warming is apparent, and the more rapid warming that has taken place since the mid-1990s continued until the time of the last reported data in 2003 (FRS, 2005). Similarly, inshore temperature data from Wylfa Power Station and Amlwch in North Wales showed a pattern of warming from 1967 onwards, as did temperatures at Port Erin in the Isle of Man (Joyce, 2006, www.cefas.co.uk/data/seatempandsal/). Several temperature time-series, including fortnightly records from a fixed station off the SW coast of the Isle of Man (the Cypris station), a more recent shorter series from a mooring in the western Irish Sea (Gowen, AFBI, Belfast), and two series of combined satellite and ship-recorded data compiled by the Climate Diagnostics Center, National Oceanographic and Atmospheric Administration of the US Department of Commerce (Figure 5.1.2) indicate a general warming trend in the Irish Sea since 1960, with particularly high temperatures in 1998 (ICES, 2006).


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Figure 5.1.2 Sea surface temperature in the Irish Sea from 1960 to 2006 (ICES, 2006b). High-intensity, near ‘real-time’ temperature (and in some cases salinity) data are available from monitoring buoys in the Irish Sea (Liverpool Bay, Aberporth, M2), the Bristol Channel/Celtic Sea (M5, Pembroke, Scarweather) and west of Ireland (M1, M3, M4, M6, K2, K4), operated by the Marine Institute (Ireland), CEFAS (UK), and the UK Met. Office (see www.cefas.co.uk/WaveNet/default.htm). Scottish monitoring stations exist at Loch Maddy (North Uist), Mallaig, and Loch Ewe (www.frs-scotland.gov.uk). The North Atlantic Oscillation index (NAO) is a measure of the difference in normalized sea level pressure between Iceland and the subtropical eastern North Atlantic. When the winter NAO index is positive, this coincides with colder and drier conditions over the western North Atlantic and warmer, wetter conditions in the eastern North Atlantic. During a negative NAO, a weakening of the Icelandic low and Azores high decreases the pressure gradient across the North Atlantic and tends to reverse the effect. The winter NAO experienced a strong negative phase in the 1960s, becoming more positive in the 1980s and early 1990s. It remained mainly negative from 1996 to 2004, but became positive in 2005 (6.7 mbar). Input of fresh water Several rivers discharge fresh water into the ecoregion and influence the circulation patterns; these are notably the River Loire, the Severn, and the Irish rivers Lee and Blackwater in the Celtic Sea (Figure 5.1.3). To the west of Ireland, fresh water discharges from Irish rivers (e.g. Shannon and Corrib) and those further afield (e.g. Loire, Severn) interact with Eastern North Atlantic Water. River inputs into the Irish Sea and the Malin Sea north of Ireland are locally important in reducing salinity in these areas. Because of the complex fjordic nature of the western coast of Scotland there is also a substantial fresh-water input from the numerous sea-lochs, notably the Firth of Lorne sealoch system (Nolan and Lyons, 2006).


Figure 5.1.3 Discharges from rivers affecting the western Irish Shelf: the river Loire (upper panel) and rivers

Shannon and Severn (lower panel). Note different scales on Y-axes. Broad-scale climate and oceanographic features See general text on this topic in the separate section on the NE Atlantic (Section 2.9). Phytoplankton For most of the Celtic Seas ecoregion productivity is reasonably strong on the shelf but drops rapidly west of the shelf break. Based on CPR greenness records for this area the spring bloom occurs around April and collapses by October, although in recent years it has continued into December. CPR data also suggest that there has been a steady increase in phytoplankton colour index across the whole area over at least the past 20 years. Phytoplankton productivity and taxonomic composition in the Celtic Sea has been shown to depend on water column structure. Diatoms dominate well-mixed areas with high nutrient content and display high rates of productivity, while dinoflagellates and microflagellates are found in stratified waters exhibiting lower rates of productivity (Raine et al., 2002). Certain oceanographic conditions can lead to the formation of toxic algal blooms around Irish coasts, with the highest occurrence noted along the southwest of Ireland. Large harmful algal blooms recorded in 2005 were associated with the dinoflagellate Karenia mikimotoi and caused mortalities to benthic and pelagic marine organisms at a scale that has not previously been observed (Silke et al., 2005). Zooplankton As is true of the adjacent North Sea, the overall abundance of zooplankton in this region has declined in recent years. CPR areas C5, D5, and E5 all show substantial drops in Calanus abundance and these are now below the long-term mean. Calanus finmarchicus is known to overwinter in the Faroe-Shetland channel and the abundance of these is known to have been reduced in recent years. Distribution of this species in deep waters further south is unknown. More detailed information should be available from the CPR programme, but this is not available at present. Zooplankton monitoring data are available from one station (“L4”) in the English Channel. This station is influenced by seasonally stratified waters and is maintained by Plymouth Marine Laboratory (ICES, 2006a). Whether or not changes in the zooplankton community evident at this site are representative of changes and trends in the wider “Celtic Seas” remains uncertain, further analyses of CPR data or additional information from static sampling stations (e.g. Nash and Geffen, 2004) are urgently needed to clarify the situation. The ten most abundant zooplankton taxa at “L4” have been ranked according to their annual mean proportion of the total zooplankton (Table 5.1.1). In 2005, major changes in the zooplankton composition were reported. Not only has the rank order of the top ten species changed, but new groups, Echinoderm larvae, Noctiluca scintillans, Siphonophores, and C. helgolandicus appear in the dominant species for the first time, contributing 4.6% to 3% of the total zooplankton abundance respectively. In addition, Ps. elongatus, which was the most abundant species during the period 1988–2004


when it contributed nearly 12% of the total zooplankton abundance, represented only 2.3% of the zooplankton community in 2005. Ps. elongatus abundance in 2005 is the lowest abundance observed over the whole time-series (53 ind. m−3). Peaks of high zooplankton abundance and chlorophyll a concentration are regularly observed in spring and late summer/beginning of autumn, the latter resulting from intense summer dinoflagellate blooms in some years. Zooplankton at L4 shows two decreasing trends from 1988 to 1995 and from 2001 to 2005. This is mainly the result of relatively low abundances of the spring species Paracalanus, Pseudocalanus, and A. clausi. Small copepods like Oncaea, Oithona, and Corycaeus contribute greatly to the total zooplankton population. Table 5.1.1 Percentages and averages of the top taxa at Plymouth “L4” station during the sampling period

1988–2005 time-series and in 2005.

Rank Taxa

% total zooplankton 1988–2004

% total zooplankton 2005

Yearly average 1998–2004 (N/m3)

2005 average (N/m3)

1 Pseudocalanus 11.74 2.32 380 54 2 Oithona 11.30 6.23 366 144 3 Oncaea 11.11 7.69 360 178 4 Paracalanus 9.53 4.23 309 98 5 Temora 9.19 8.52 298 198 6 Cirripeda nauplii 8.69 7.93 281 184 7 Acartia clausi 6.18 2.74 200 64 8 Evane 5.85 2.25 190 52 9 Appendicularia 2.59 1.22 84 28

10 Corycaeus 2.25 5.72 73 133 Total 78.43 48.90 2540.62 1133.30 N/m3 3239.60 2320.40 Benthos, larger invertebrates (cephalopods, crustaceans etc), biogenic habitats The major commercial invertebrate species in the Celtic Seas ecoregion is Norway lobster (Nephrops norvegicus). It is targeted by trawl fisheries on the continental shelf west of Scotland, on the Rockall plateau, and both south and west of Ireland. Cuttlefish (Sepia officinalis) is also exploited in the Celtic Sea. Major fisheries dredging for scallops and some smaller bivalves exist in the western Channel, Irish Sea, and west of Scotland. Pot fisheries exploit lobster Homarus gamarus and brown crab Cancer pagurus in the waters around the Channel Islands (French landing about 150 t year−1), and west of Scotland. In addition to major aquaculture activity for oysters and mussels, some beds of wild oysters and buried bivalves such as cockles Cardium edule are exploited by professional and recreational fisheries (for example in Morecombe Bay). The most abundant cephalopods species in the Celtic Sea and west of Ireland are Loligo forbesi and Illex coindetii which are mainly found close to the shelf break, while Alloteuthis subulata is a common species found close to shore in water depths of less than 75 m (Lordan, 2001). Ellis et al. (2000) provided a review of benthic community structure in the Irish Sea and described six distinct assemblages. Plaice and dab dominated on fine substrates in inshore waters, whereas sea urchins and sun-stars dominated on the coarser substrates further offshore. Thickback sole Microchirus variegates and hermit crabs were typical of the transitional zone, while Norway lobster and witch (Glyptocephalus cynoglossus) dominated on the muddy sediments in the central Irish Sea. Beds of Alcyonium digitatum (Dead man’s finger) occurred on coarse substrates throughout the study area, whereas common spider crabs were only dominant in the Bristol Channel (Maja assemblage). The common starfish (Asterias rubens) was an important component of all assemblages and the distribution of these assemblages was primarily correlated with depth, temperature, and substrate type. Kaiser et al. (2004) added a distinct sandbank type habitat off the Welsh coast, typified by low species diversity and shared indicator species such as the weever fish Echiichthys vipera, the shrimp Philocheras trispinosus, and the hermit crab Pagurus bernhardus. Over 340 species of invertebrate and fish were captured in a survey of the epibenthos in ICES Areas VIIf-h (Ellis et al., 2002), the most ubiquitous species being the hermit crab Pagurus prideaux and the spotted dragonet Callionymus maculatus, both of which are major prey items for commercial fish (Pinnegar et al., 2003). Two epibenthic assemblages predominate in the Celtic Sea. The first is dominated by the anemone Actinauge richardi (41.8% of the faunal biomass) and occurs along the shelf edge and slope in waters 132–350 m deep. The second assemblage is more widely distributed on the continental shelf (depth range: 66–232 m) and P. prideaux dominates along with other mobile invertebrates (shrimps and echinoderms), although there are some spatial differences in assemblage structure and relative abundance.


Rees et al. (1999) provided a comparison of benthic biodiversity in the North Sea, English Channel, and the Celtic and Irish Seas. Similar infaunal assemblages were encountered on both the eastern and western UK coasts in comparable environmental conditions. Grab stations in the easternmost part of the English Channel, southern North Sea, and within the Bristol Channel, supported very sparse infauna communities associated with sandy sediments. The highest diversities were generally encountered off the NE and SW English coast. Densities were also relatively high in coastal waters off Morecambe Bay, NW England. Heath (2005) used the abundance of benthic invertebrate larvae in CPR (continuous-plankton-recorder) data, to establish trends in benthic production for the ‘Celtic Seas’ ecoregion. Based on these data the author reported an increasing long-term trend in benthic production (by 0.8 g C m2 y−1) between 1973 and 1999. Biogenic reefs of horse mussels Modiolus modiolus, maerl, and Serpulid worms occur in specific locations (Irish Sea, West coast of Scotland). The latter support benthos of conservation interest, such as sea fans and structurally complex bryozoans. Offshore areas on the shelf slope support reefs of deep-water corals such as Lophelia pertusa. Fish community The northern part of this ecoregion (Irish Sea, West of Ireland, and western Scotland) has important commercial fisheries for cod, haddock, whiting, and a number of flatfish species. Hake Merluccius merluccius and anglerfish Lophius spp. are also fished across the whole area. The Rockall plateau is subject to an important haddock Melanogrammus aeglefinus and small-scale Nephrops fishery. Commercial fisheries for cod Gadus morhua, plaice Pleuronectes platessa, and sole Solea solea are conducted in the Irish Sea. The whole area is characterized as a spawning area for a number of key wide-ranging, migratory species, notably mackerel Scomber scombrus, horse mackerel Trachurus trachurus, and blue whiting Micromesistius potassou. These species are also commercially exploited within the area. Key pelagic species on the continental shelf are herring Clupea harengus, considered as consisting of a number of different stocks, as well as sardine Sardina pilchardus in the southern part of the area, and sprat Sprattus sprattus, particularly in the Celtic Sea. The area accommodates considerable stocks of argentines (two species) and also large numbers of small mesopelagic myctophids along the shelf break. The shelf slope (500–1800 m) comprises a distinct species assemblage, including roundnose grenadier Coryphaenoides rupestris, black scabbard fish Aphanopus carbo, blue ling Molva macrophthalma, and orange roughy Hoplostethus atlanticus, as well as deep-sea squalids (sharks) and macrouridae (see Section 3.12). Stock assessments have been mostly unreliable for these species so far. However, strong evidence exists that some stocks have been severely depleted by the deep-water fisheries carried out in this area. All these fish are characterized as being long-lived, slow-growing, and having a low fecundity, making them very vulnerable to overfishing. More than 170 species of marine fish have been recorded from within the Irish Sea (Ellis et al., 2002a). Trawl surveys in this region (Parker-Humphreys, 2004) have revealed that dab Limanda limanda, plaice, solenette Buglossidium luteum, and common dragonet Callionymus lyra are the most abundant species, along with large numbers of poor-cod, whiting, and sole. Dab, solenette, and scaldfish (Arnoglossus laterna), all non-commercial species, are thought to have increased in recent years, whereas hake, dragonets, and pogge Agonus cataphractus have become less abundant. Red gurnards Aspitrigla cuculus are also thought to have increased in recent years. The Celtic Sea groundfish community consists of over a hundred species and the most abundant 25 comprise 99 percent of the total estimated biomass and around 93 percent of total estimated numbers (Trenkel and Rochet, 2003). Population and community analyses have shown that fishing has impacted a number of commercial species, primarily because individuals of too small a size have been caught and discarded in the past (Trenkel and Rochet, 2003; Rochet et al., 2002).The size structure of the fish community has changed significantly over time, and a decrease in the relative abundance of larger fish has been accompanied by an increase in smaller fish (4–25 g) (Blanchard et al., 2005; Trenkel et al., 2004). Temporal analyses of the effects of fishing and climate variation suggest that fishing has had a stronger effect on size-structure than changes in temperature. A marked decline in mean trophic level of the fish community over time has been documented (Pinnegar et al., 2003), resulting in a reduction in the abundance of large piscivorous fishes such as cod and hake, and an increase in smaller pelagic species which feed at a lower trophic level. Since 1990 the non-exploited species Capros aper has become particularly abundant in French and UK survey catches. This phenomenon has been reported as occurring elsewhere in the North Atlantic, including the Bay of Biscay (Farina et al., 1997) and offshore seamounts (Fock et al., 2002). Limited information is available for the west coasts of Scotland and Ireland; however, Scottish groundfish surveys between 1997 and 2000 revealed declines in most commercial fish stocks, including haddock, whiting, Norway pout, herring, and hake. Similarly, Irish groundfish surveys revealed a downward trend in the biomass and abundance of cod, whiting, and hake between 1993 and 2000, in particular in the latter part of the time-series. Megrim were somewhat more abundant in recent years, particularly along the coasts of southern Ireland and the Celtic Sea shelf edge (Mahé, 2001).


Demersal elasmobranchs The Celtic Seas ecoregion covers west of Scotland (Division VIa), Rockall (Division VIb), Irish Sea (Division VIIa), Bristol Channel (Division VIIf), the western English Channel (Division VIIe), and the Celtic Sea and west of Ireland (Divisions VIIb-c, g-k), although the southwestern sector of ICES Division VIIk is contained in the oceanic northeast Atlantic ecoregion. This ecoregion broadly equates with the area covered by the northwestern waters RAC. Whereas some demersal elasmobranchs, such as spurdog Squalus acanthias and lesser spotted dogfish Scyliorhinus canicula, are widespread throughout this region, there are some important regional differences in the distributions of other species. Other than spurdog and tope, the main species of shark taken in demersal fisheries in this ecoregion are lesser spotted dogfish, smooth-hounds Mustelus spp., and greater spotted dogfish Scyliorhinus stellaris. Sixteen species of skate and ray are recorded in the area, the most abundant skates being thornback ray Raja clavata, cuckoo ray Leucoraja. naevus, blonde ray R. brachyura, spotted ray R. montagui, undulate ray R. undulata, common skate Dipturus batis, shagreen ray L. fullonica, and smalleyed ray R. microocellata. Other batoids (stingray Dasyatis pastinaca, marbled electric ray Torpedo marmorata, and electric ray T. nobiliana) may be observed in this ecoregion, although they are more common in more southerly waters. These are generally discarded if caught in commercial fisheries and are not considered in this report. Landings of rays appear as a series of peaks and troughs, with lows of approximately 14 000 t in the mid-1970s and 1990s, and highs of just over 20 000 t in the early and late 1980s and late 1990s. While landings have fluctuated considerably over the time-series, they have been in a constant decline since 2003, and the 2006 landings of approximately 10 000 t are the lowest in the time-series. This decline in landings is thought to be mainly due to a combination of increased regulation and changes in consumption (ICES, 2007).

Figure 5.1.4 Demersal elasmobranchs in the Celtic Seas. Total landings (tonnes) of Rajidae by nation in the

Celtic Seas from 1973–2006 (Source: ICES). Trophic web For the Celtic and Irish Seas, two sources of fish stomach data have recently been collated and these are described by Pinnegar et al. (2003). UK researchers collected stomachs for 66 species during annual groundfish surveys from 1986 to 1994. French researchers (du Buit and co-workers) sampled stomachs of seven species aboard commercial fishing vessels, throughout the years 1977 to 1992 (in all seasons). The main predator species in the Celtic Sea (hake, megrim, monkfish, whiting, cod, saithe) are generalist feeders which exhibit size-dependent, temporal, and spatial prey-switching behaviour (Pinnegar et al., 2003; Trenkel et al., 2005). Consequently, utilization of a conventional multispecies assessment model such as MSVPA in such a system would be unlikely to yield useful insights. Overall, higher prey densities in the environment coincide with higher occurrences of particular prey species in predator stomachs (Trenkel et al., 2005). Blue whiting was found more often in predator stomachs over the shelf edge during the summer months while mackerel and Triopterus spp were relatively more prevalent in stomachs sampled on the continental shelf during the winter half-year. Little is known concerning trophic interactions among fish species west of Ireland and northwest Scotland (but see du Buit, 1989, 1991a, 1991b). No major studies of forage fish have been conducted in the ecoregion. Sand eel Ammodytes spp., sprat, and Norway pout Trisopterus esmarki are known to be present, but their role and importance in the ecosystem remains unclear. For cod in the Irish Sea, the decapod Nephrops norvegicus is known to be an important prey item (Armstrong, 1982). Consequently, Bennett and Lawler (1994) attempted to model cod-Nephrops, a simple multispecies model. Whiting, Norway pout, and Nephrops are known to be important for monkfish in the Irish Sea (Crozier, 1985). To the northwest of Scotland there have been additional studies focusing on inshore demersal assemblages (e.g. Gibson and Ezzi, 1987).


According to Heath (2005) fish taken from the shelf edge areas of the Celtic Seas tend overall to be less planktivorous and from a higher trophic level than those in the North and Baltic Seas (Heath, 2005). The secondary production required per unit of landed fish from the southern part of the Celtic Seas is suggested to be twice that for North Sea fish. In the Celtic Seas benthos production has been suggested to be a ‘bottom-up’ driver for fisheries production, which seems to be independent of variability in plankton production. As this situation is very different to the situation in the North Sea (see NS section), climate change and fishing pressures might be expected to influence these regional fisheries in very different ways. Overall, there appear to be strong spatial patterns in the fish food web structure and function, which should be important considerations in the establishment of regional management plans for fisheries (Heath, 2005). Heath (2005) argues that, because the blue whiting fishery is conducted mainly off the continental shelf, there is no rationale for a foodweb connection between the bulk of the blue whiting catch and the other landed species from the Celtic Sea and west of Scotland. However, Pinnegar et al. (2003) and Trenkel et al. (2005) have both highlighted the importance of this species as a prey for fish on the shelf edge, notably for hake and megrim. Vulnerable species Skates are arguably the most vulnerable of exploited marine fishes because of their large size, slow growth rate, late maturity, and low fecundity. Dulvy et al. (2000) discussed the disappearance of skate species (Dipturus oxyrhinchus, Rostooraja alba, and D. batis) in the Irish Sea, and the widespread decline in the abundance of smaller species. In 2006 the Working Group on Fish Ecology (WGFE) evaluated the status of rarer elasmobanchs throughout the ‘Celtic Seas’ ecoregion. The Celtic Sea was highlighted as a particularly important area for common skate (D. batis), electric ray (Torpedo nobiliana), and shagreen ray (Leucoraja fullonica), whereas the English Channel is an important area for undulate ray (Raja undulata) and stingray (Dasyatis pastinaca) (ICES, 2006b). The blackspot (red) seabream (Pagellus bogaraveo) was previously an important target species of English fisheries in the 1930s (Desbrosses, 1932), catches in the Celtic Seas declining well before the cited collapse of the fishery in region G (see this chapter for a longer account on this species). The species can be considered as commercially extinct in the Celtic Seas. The red lobster (Palinurus elephas) was exploited by pot fisheries prior to the late 1970s, and current catches of this species can be considered as residual. As mentioned above, several species of deep-water fish are considered as being severely depleted and meriting protection (see Section 3.12). Birds, mammals, and large elasmobranches Basking shark (Cetorhinus maximus) are seen throughout the Celtic Sea, Irish Sea, and Northern Shelf region, from April through to October, but the stock seems to be severely depleted. Basking shark is protected within British territorial waters. Blue shark (Prionace glauca) are found in the summer in the southern part of the area. They are subject to a variety of fisheries, both recreational and directed (longlines and gillnet) as well as bycatch in offshore tuna fisheries. Porbeagle (Lamna nasus) and tope (Galeorhinus galeus) are also targeted in both recreational and commercial fishing. Six species of cetaceans are regularly observed in this Advisory Region (Reid et al., 2003). Minke whale Balaenoptera acutorostrata is found throughout the region, particularly off western Scotland and Ireland. SCAN surveys and observer programmes on ships of opportunity have recorded that bottlenosed dolphin Tursiops truncatus occur in large numbers off western and southwestern Ireland and in smaller numbers throughout the region. Common dolphin Delphinus delphis are widely distributed in shelf waters, but especially in the Celtic Sea and adjacent areas. White-beaked dolphin and white-sided dolphin (Lagenorhynchus albirostris and L. acutus) occur over much shelf area, but are less common in the southwest. Harbour porpoise Phocoena phocoena is the smallest, but by far the most numerous of the cetaceans found in the Celtic Seas ecoregion, particularly southwest of Ireland and west of Scotland (Hammond et al., 2002; Wall et al., 2004). Santos et al. (2004) suggested that whiting and sandeels are the most important prey for porpoises around the coasts of Scotland, comprising around 80% of the diet. Grey seals (Halichoerus grypus) are common in many parts of the area, with population estimates ranging from approximately 50 000 to 110 000 animals (SCOS, 2005). The majority of individuals are found in the Hebrides and in Orkney, although some 5000–7000 are thought to exist in the Irish and Celtic Seas (Kiely et al., 2000). Studies of grey seal diet in the western Irish Sea reveal that the predominant prey species (Norway pout, bib, poor cod, whiting, plaice) are not the principle target species for commercial fisheries in this region (Kiely et al., 2000). However, a recent study (Hammond and Harris, 2006) of seal diets off western Scotland revealed that grey seals may be an important predator for cod, herring, and sandeels in this area. Common seals (Phoca vitulina) are also widespread in the northern part of


the ecoregion with around 15 000 animals estimated (SCOS, 2005). Smaller numbers are seen in Ireland (ca. 4000) and very few further south. In 2002, the ICES Working Group on Seabird Ecology reported seabird population estimates within all ICES areas. For ICES Division VIa west of Scotland a total of 1.2 million pairs of breeding seabirds were reported. Auks, predominantly the common guillemot (Uria aalge), razorbill (Alca torda), and the Atlantic puffin (Fratercula arctica) accounted for 51% of the total, while petrels (including fulmar (Fulmarus glacialis), storm petrel (Hydrobates pelagicus), and Manx shearwater (Puffinus puffinus)) accounted for 29%, Northern gannet accounted for 10%, and gulls (particularly kittiwake and herring gull) 9% (ICES, 2002). In the Irish Sea, Bristol Channel, and English Channel (ICES Divisions VIIa,d,e,f) gulls predominate (47%, 66%, 90%, and 68%, respectively), in particular black-headed, lesser black-backed and herring gulls as well as guillemots. Petrels (fulmar and storm-petrel) dominate in the west of Ireland and Celtic Sea region (Divisions VIIb,g,j 48%, 60%, and 79%, respectively), but there are also large breeding colonies of kittiwake, guillemot, and gannet. Climate change is likely to impact significantly on seabird populations. The breeding success of some seabird populations in the Celtic Sea has already been linked to climatic fluctuations in the North Atlantic, such as the North Atlantic Oscillation (NAO). Projected consequences of global warming, such as sea level rises, increased storminess, and rises in sea/air temperatures are also likely to have a direct impact on seabird populations. 5.2 Human impacts on the ecosystem 5.2.1 Fishery effects on benthos and fish communities The impact of fishing activities on shelf fish communities is unclear, although there are numbers of severely depleted stocks e.g. cod, whiting, plaice, and hake. Furthermore, the level of discarding in some fisheries can be significant. Analysis of discarding levels of the demersal fleet around Ireland has shown that a significant proportion of the catch is discarded (Borges et al., 2005). Discarding levels differ between the different fleets but have been shown to be up to two thirds of the total catch. In this study whiting, haddock, megrim, and dogfish are the main species discarded by otter trawlers, while the Scottish seiners discard mostly whiting, haddock, and grey gurnard and beam trawls mostly dab and plaice. The majority of these discard species consist of immature fish and discarding appears to have been increasing in recent years. Cetacean bycatch in fisheries has been acknowledged to be a threat to the conservation of cetaceans in this ecoregion (CEC, 2002; Ross and Isaacs, 2004). As in other areas this mainly affects small cetaceans, i.e. dolphins, porpoises, and the smaller-toothed whales. Species caught in the region are primarily the harbour porpoise, common dolphin, striped dolphin, Atlantic white-sided dolphin, white-beaked dolphin, bottlenose dolphin, and long-finned pilot whale (CEC, 2002a). However, other larger cetaceans, such as the minke whale, can also be affected. An extensive review of the bycatch of cetaceans in pelagic trawls was carried out for Greenpeace in 2004 (Ross and Isaacs, 2004). This report considered published and anecdotal information. In the Celtic Seas the report identified a small number of fisheries where cetacean bycatch could be documented. These were:

• Bass fishing in the western Channel; • Mackerel and horse mackerel trawling SW of Ireland; • Gillnetting for hake in the Celtic Sea.

In the last two cases, the number of animals caught was low; however, it is probably higher in the bass fishery and has attracted considerable public attention. The report identified that many countries had initiated cetacean bycatch monitoring programmes, and had generally found little or no evidence that serious bycatch had occurred. Major environmental signals and implications No obvious environmental signals were identified that should be considered in assessment or management in this area. The major trends in the ecosystem noted above are the steady warming of the area, particularly in the context of the slope current. Surface waters of the Rockall trough have been steadily warming for some years and are currently at an all time high. The general and continuing reduction of copepod abundance and recent changes in zooplankton composition throughout the region are also causes of major concern, given the key role that these organisms play in the food web. In 2006 the Working Group on the Assessment of Northern Shelf Demersal Stocks (WGNSDS) considered the influence of sea temperatures on cod recruitment (ICES, 2006c) in the Irish Sea. The time-series of Irish Sea cod recruitment exhibited a decline in the 1990s, coincident with an increase in sea surface temperatures (SST). Analysis revealed a clear tendency for strong recruitment residuals to coincide with prominent negative SST residuals, and for weak recruitment to coincide with strong positive SST residuals. Further biological studies are needed to establish the


causal mechanisms for any association between cod recruitment residuals and SST, before such an association could be considered to have any predictive power in the future. If causal mechanisms were established, the consequence would be an expectation of a continued high probability of very weak year classes occurring while SSB remains low and SST continues to vary around the elevated values observed since the 1990s. This does not preclude the possibility of strong recruitment occurring in any year, but the probability is likely to be much lower than was the case in the 1960s–1980s when SST was lower and SSB (and consequently egg production) was relatively high. Increasing temperature and changes in zooplankton communities are likely to have an impact on the life histories of many species. The timing and location of spawning by all species is also likely to be affected by warming, as has been observed in the North Sea (Greve et al., 2001). Southward et al. (1988) demonstrated that the abundance of herring Clupea harengus and pilchard Sardina pilchardus occurring off the southwest of England, closely corresponded with fluctuations in water temperature. Sardine were generally more abundant and extended further to the east when climate was warmer, whilst herring were generally more abundant in cooler times. This pattern has apparently been occurring for at least 400 years, and major changes were noted in the late 1960s as waters cooled and spawning of sardine was inhibited. In recent years herring populations have declined throughout the Celtic Seas ecoregion, but is unclear whether sardine have increased in abundance. The recent warming trend in the northeast Atlantic has coincided with a northward shift in the distribution of some fish species from southerly waters (Quero et al., 1998; Beare et al., 2004). Seabass Dicentrarchus labrax and red mullet Mullus surmuletus populations around British coasts have been growing in recent years. Similarly sightings of blue-fin tuna Thunnus thynnus, triggerfish Balistes capriscus, thresher Alopias vulpinus, and blue sharks Prionace glauca, sting-rays, turtles, and seahorses Hippocampus spp. are all becoming more commonplace (Stebbing et al., 2002). Analysis of fish taxa in the western English Channel over a 26-year period indicated that nine species responded strongly to increasing sea temperatures (Genner et al., 2004). A parallel analysis of 33 species in the Bristol Channel over 22 years showed similar macroscopic trends, with one species declining in abundance with warming (the sea snail Liparis liparis), and nine increasing (Genner et al., 2004). The widespread and sudden increase in occurrence of non-commercial species such as Capros aper in the Celtic Sea particularly after 1990 (Pinnegar et al., 2003) might indicate some change in oceanic conditions, as is true of increased sightings of ocean sunfish Mola mola (Houghton et al., 2006), but mechanisms and consequences are poorly understood. As is true elsewhere in the NE Atlantic, the Celtic Seas ecoregion has recently experienced an unprecedented increase in the numbers of snake pipefish, Entelurus aequoreus (Harris et al., in press; Kloppmann and Ulleweit, in press). Kirby et al. (2006) speculate that the increased abundance of larval and juvenile E. aequoreus in CPR plankton samples as far west as the Mid-Atlantic Ridge may coincide with a rise in winter, spring, and summer sea temperatures (January-September), when the eggs of E. aqueoreus, which are brooded by the male, are developing and the larvae are growing in plankton. Data gaps In general this ecoregion has attracted less attention than areas such as the North Sea. It is probably not that data do not exist, but that they have not been correlated and integrated. For example, the ICES Annual Ocean Climate Status Summary does not address this area as a whole. The WG would recommend that ICES develops a more integrative approach so that all output data can be matched up easily. The CPR programme samples within the area, but detailed breakdown of these data has not been carried out. There is also no single assessment working group responsible for the fisheries in the region. These are covered by nine different groups, including both northern and southern shelf demersal WGs. This makes the integration of data by ecoregion more complex. There is currently no multi-species working group for this region, and hence there has been no coordinated effort towards exploring predator-prey relationships and inter-dependencies among commercial species. References Armstrong, M. J. 1982. The predator-prey relationships of Irish Sea poor-cod (Trisopterus minutus L.), pouting

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Heath, M. R. 2005. Regional variability in the trophic requirements of shelf sea fisheries in the northeast Atlantic, 1973-2000. ICES Journal of Marine Science, 62: 1233–1244.

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Rees, H. L., Pendle, M. A., Waldock, R., Linpenny, D. S., and Boyd, S. E. 1999. A comparison of benthic biodiversity in the North Sea, English Channel and Celtic Seas. ICES Journal of Marine Science, 56: 228–246.

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Reid, J. B., Evans, P. G. H., and Northridge, S. P. 2003. Atlas of Cetacean distribution in north-west European waters. Joint Nature Conservancy Committee, Peterborough, UK.

Rochet, M-J., Péronnet I., and Trenkel, V. M. 2002. An analysis of discards from the French trawler fleet in the Celtic sea. ICES Journal of Marine Science, 59: 538–552.

Santos, M. B., Pierce, G. J., Learmonth, J. A., Reid, R. J., Ross, H. M., Patterson, I. A. P., Reid, D. G., and Beare, D. 2004. Variability in the diet of harbour porpoises (Phocoena phocoena) in Scottish waters 1992–2003. Marine Mammal Science, 20: 1–27.

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5.3 Assessments and advice 5.3.1 Assessments and advice regarding protection of biota and habitats No information. 5.3.2 Assessments and advice regarding fisheries Fisheries in the Celtic Sea and Western Channel (Divisions VIIb,c,e,f,h,j,k) Demersal fisheries in the Celtic Sea and Western Channel are mixed fisheries, with many stocks exploited together in various types of fisheries. Therefore, management advice considers both the state of individual stocks and their simultaneous exploitation in demersal fisheries. The stocks in poorest condition, particularly those outside precautionary limits, necessarily become the overriding concern for the management of fisheries that target or have bycatches of the stock. As trends in stocks of various species generally do not run parallel, advice provided for individual species may have effects on the advised fishing mortalities for a group of co-harvested species. The main interactions (Table 5.3.2.1) amongst stocks in the Celtic Sea, Southwest of Ireland, and Western Channel, are between:

• anglerfish, megrim, and hake in the otter board trawl fishery in medium to deep water; • Nephrops, cod, and whiting in the Nephrops fishery in the Celtic Sea; • gadoids (cod, haddock, and whiting) within the trawl fishery for roundfish, mainly within Divisions VIIf,g; • sole and plaice in the beam trawl fishery in Divisions VIIf,g and VIIe; • haddock, whiting, cod, sole, plaice, hake, megrim, anglerfish, squid, elasmobranchs, and other species within

the mixed demersal trawl fisheries.

The directed fisheries for hake (trawl, longlines, and gillnets) have few interactions with other stocks. The demersal fisheries on cod, haddock, whiting, sole, and plaice in ICES areas VIIbc,e–k are predominantly carried out by Belgian, French, Irish, and UK fleets. The Nephrops fisheries are predominantly carried out by French, Irish, and Spanish fleets. The demersal fisheries on hake, anglerfish, and megrim are predominantly carried out by French, Irish, Spanish, and UK vessels. Effort series (in fishing hours) for Belgium, France, Ireland, and England are presented in Figures 5.3.2.1–5.3.2.13. Gillnet effort is not presented in these figures since there is no straightforward or commonly agreed method to calculate effort for gill netters. Total effort by ICES division and gear since 1999 is presented in Figure 5.3.2.1. Since 1999 effort has mainly decreased in Divisions VIIfg and VIIjk. In the other areas effort increased or remained more or less stable. Demersal fisheries in the Southern Shelf are most active in ICES Divisions VIIe, f, and g. Figures 5.3.2.2–5.3.2.7 summarize the effort by gear type. The main gear type used in all ICES Divisions VIIbc,e–k is the otter trawl. Note that a considerable amount of effort could not be attributed to any type of gear (N_A in the figures). This concerns mainly French vessels operating in Division VIIe. It is believed that these vessels use mostly otter trawlers. Beam trawlers operate predominantly in ICES Divisions VIIe and VIIfg, and to a lesser extent in VIIh. The main fishing activity of Nephrops trawlers is in ICES Divisions VIIfg and to a lesser extent in Divisions VIIbc, VIIh, and VIIjk. Effort of demersal seiners is low compared to the other gear types. Figures 5.3.2.8–5.3.2.13 show the effort by country. Since 1999, French vessels fished between 0.9 and 1.1 million hours in ICES Divisions VIIbc,e–k, Ireland, and the United Kingdom fished between 0.2 and 0.4 million hours, and Belgium fished less than 0.1 million hours. The Belgian fleet is mainly active in Divisions VIIfg. French vessels operate over the entire area VIIbc,e–k, but mostly in Divisions VIIe, VIIfg, and VIIh. Since 1999, French effort in VIIfg has declined. The current French effort in that area is now almost halved compared to 1999. Irish effort is divided over Divisions VIIbc, VIIfg, and VIIjk. Since 2003, some Irish vessels that used to operate in Divisions VIIjk moved their effort partly to Divisions VIIfg. That explains the decrease in overall effort in VIIbc compared to the increase in effort in VIIfg since 2003. Finally, the UK fleet is also active over the entire area, with the highest effort levels in Division VIIe.


Fisheries to the West of Scotland and Rockall (Divisions VIa-b) The main fleets operating in Division VIa include the mixed roundfish otter trawl fleet, the Nephrops otter trawl fleet, the otter trawl fleet targeting anglerfish, megrim, and hake, and the fleet targeting saithe and/or deep-sea species. To a large extent, the roundfish fishery in Division VIa is an extension of the similar fishery in the North Sea. The demersal fisheries in Division VIa are predominantly conducted by otter trawlers fishing for cod, haddock, anglerfish, and whiting, with bycatches of saithe, megrim, and lemon sole. The majority of the vessels in the demersal fishery are locally-based Scottish trawlers using light-trawls, but trawlers from Ireland, Northern Ireland, England, France, and Germany also participate in this fishery. The importance of Scottish seiners mainly targeting haddock has been declining in recent years as many of these vessels have been converted to trawlers. Part of the fleet of light trawlers has diversified into a fishery for anglerfish that has been expanding into deeper water off the northern coast of Scotland. Bycatches in this fishery include megrim, ling, and tusk. About 200 Scottish trawlers also take part in the fisheries for Nephrops on inshore grounds. In recent years Irish vessels have also been targeting Nephrops in Division VIa, mainly on offshore grounds. These Nephrops vessels also land smaller quantities of haddock, cod, whiting, and small saithe, but discard large amounts of whiting and haddock. The development of a directed fishery for anglerfish has led to considerable changes in the way the Scottish fleet operates. Part of this is a change in the distribution of fishing effort; effort in the roundfish fisheries has shifted away from the traditional inshore areas to more offshore areas and deeper waters. The expansion in area and depth-range of the fishery has been accompanied by the development of specific trawls and vessels to exploit the stock. These vessels mainly use large twin-rig otter trawls with >100 mm mesh. A smaller Irish fleet also targets anglerfish, megrim, and hake on the Stanton bank with 90 mm to 100 mm mesh. This fleet has declined in numbers in recent years although there was a fleet modernization scheme in the early 2000s whereby several large new vessels joined the fleet. More recently there has also been an Irish decommissioning scheme, involving around 40 fishing vessels (~6000 GT, 18 000 kW) which have been permanently withdrawn from the Irish fishing fleet and removed from the Register of Sea Fishing Vessels in 2005 and 2006. Several of these vessels have a track record of fishing in Division VI. The fishery for anglerfish has expanded into deeper waters with an associated increase in catches. The expansion of this fishery has been further accelerated by the diversion of fishing effort from other stocks subject to more restrictive quotas in recent years, and by market opportunities. A gillnet fishery has developed on the continental slopes to the West of the British Isles, North of Shetland, at Rockall, and on the Hatton Bank. A preliminary investigation of this fishery suggests high levels of gear loss, widespread dumping of netting, high catch and discarding levels (particularly of monkfish), and a lack of effective management. These fisheries are occurring in areas believed to have been a refuge for adult anglerfish, increasing the vulnerability of the stock to overexploitation. Immature fish are subjected to exploitation for a number of years prior to first maturity. The larger Scottish and Irish trawlers fish for haddock at Rockall when opportunities arise for good catches from the Division VIb stock. Vessels from the Russian Federation have fished for haddock and other demersal species at Rockall since 1999 when part of the Bank was designated as being in international waters. Although young saithe are caught by coastal trawlers in Subarea VI, the fishery for saithe essentially takes place on the shelf edge to the west and northwest of Scotland. Traditionally, this fishery has largely been operated by the larger deep-sea French trawlers. However, the number of these vessels has declined in recent years. Since the late 1980s, some of these vessels diverted their activity toward deep-sea species, notably orange roughy, and some medium-sized trawlers also participate in the fishery for deep-sea species during summer in some years. The pelagic fishery for herring is mainly operated by UK, Dutch, and German vessels in the north, and by Irish vessels in the south. Substantial misreporting of catches from the North Sea and between the northern and southern stocks occurred in the past, but UK licensing regulations are thought to have reduced misreporting since 1997. The Clyde herring fishery has declined sharply in the 1980s and the state of the stock is unknown. There is a directed trawl fishery for mackerel and horse mackerel in the area. The mackerel fishery mainly takes place in the fourth and first quarter of the year, when the mackerel is returning from the feeding area to the spawning area. The horse mackerel is mainly fished in the second half of the year. In addition, there are fisheries for blue whiting in the area. The industrial fisheries in Division VIa are much smaller than in the North Sea. The Scottish sandeel fishery started in the early 1980s, peaking in 1986 and 1988. It is irregular, depending on the availability of the resource and of processing facilities at Shetland, Denmark, and the Faroes. Bycatches in this fishery are unquantified and need to be described. The Norway pout fishery is conducted mainly by Danish vessels. The catch of juvenile herring and gadoids in these fisheries is unknown.


Recent fishing effort trends Figure 5.3.2.14 shows that larger-meshed whitefish demersal trawls were the most important gears in Division VIa prior to 2002, but that there has since then been a marked decline in kW-days by this category. This is principally explained by the recent, significant decommissioning schemes in the UK. Single-rig Nephrops trawls in the 70 to 99 mm mesh category are the other major gears in use and effort by these seems to have been maintained at a fairly stable level throughout the time-series. Numerous other gears generally make small contributions to the overall effort and the pattern in most of these has either been a downward trend (e.g. seine nets and midwater trawls) or fluctuation without trend (e.g. fixed nets). Taken together the picture suggests that overall, effort has declined in recent years in Area VIa and that declines in particular categories have not been compensated for by rises in other categories. No updated statistics on effort figures in Area VIb (Rockall) are available. The effort (kW-days) figures have so far been small in this area (mostly reflecting fishing at Rockall) and fewer gears are used extensively. The most important gears in use in this area are whitefish demersal trawls (particularly larger-mesh), fixed nets, and longlines. Fisheries interactions to the West of Scotland and Rockall Demersal fisheries in the area are mixed fisheries, with many stocks exploited together in various combinations in different fisheries. The extent to which the stocks are taken in the same fisheries cannot be quantified on the basis of the available data, but is qualitatively presented in Table 5.3.2.2. Roundfish are caught in otter trawl and seine fisheries, with a 120 mm minimum mesh size that comprises mixed demersal fisheries with more specific targeting of individual species in some areas and/or seasons. Cod, haddock, and whiting form the predominant roundfish catch in the mixed fisheries, although there can be important bycatches of other species, notably saithe and anglerfish in the deeper water and of Nephrops on the more inshore Nephrops grounds. Static-gear fisheries with mesh sizes generally in excess of 140 mm are also used to target cod. Saithe are mainly taken in a directed trawl fishery in deeper water along the shelf in Subarea VI. There is thought to be little bycatch of other demersal species associated with the directed fishery. Large Nephrops fisheries take place in discrete areas that comprise appropriate muddy seabed sediment. Targeted Nephrops fisheries on these grounds are taken predominantly in trawls with mesh sizes less than 100 mm (particularly in the more southerly regions) using single- or multiple-rig trawls. Nephrops fishing grounds are mainly inshore grounds, although there are smaller offshore fisheries at Stanton Bank and west of the Hebrides. The bycatch and discarding of other demersal species in the Nephrops fisheries is highly variable. There are trawl and gillnet fisheries targeting hake and anglerfish and otter trawl fisheries targeting hake, megrim, and anglerfish in Subarea VI. The catch of other demersal species associated in these fisheries is uncertain. An international fishery targets haddock, grey gurnards, and other species at Rockall using small mesh. Successful application of TACs for this stock would require that there is a simple relationship between recorded landings and effort exerted. This assumption is unlikely to be true for Rockall haddock especially when coupled with ways of evading TACs, including misreporting, highgrading, and discarding. In the case of Rockall haddock these may occur to a large extent due to the remote nature of the fishery and the processing of catches at sea by some fleets. Direct effort regulation is therefore suggested as a means of controlling fishing mortality on Rockall haddock.


Fisheries in the Irish Sea (Division VIIa) The majority of vessels in the Irish Sea target Nephrops with either single- or twin-rig otter trawls. These vessels use either 70 mm diamond mesh with an 80 mm square-mesh panel or an 80 mm diamond mesh in their codends, and (by regulation) their landings must consist of at least 35% Nephrops by live weight. These vessels have bycatches of whiting (most of which are discarded), and haddock, cod, and plaice. Twin-rig otter trawl were first introduced in the early 1990s. Recent studies show that the use of twin-rigs increases the proportion of roundfish bycatch in Nephrops fisheries compared with single-rig otter trawls. Nephrops catches are highly seasonal, with the highest Nephrops catches seen in the summer months. Catch rates are also dependent on tidal conditions, with higher catches during periods of weak tide. The roundfish fisheries in the Irish Sea are conducted primarily by vessels from the UK and Ireland. A Northern Irish semi-pelagic trawling for cod and whiting developed in the early 1980s. As the availability of whiting declined the fleet switched to mainly targeting cod and haddock. Irish, Northern Irish, and English and Welsh otter trawlers target plaice, haddock, whiting, and cod, with smaller bycatches of anglerfish, hake, and sole. Some Irish vessels participate in a fishery for rays in the southern Irish Sea. Since 2001, these trawlers have adopted mesh sizes of 100–120 mm and other gear modifications, depending on the requirements of recent EU technical conservation regulations and national legislation. A beam trawl fishery also takes place mainly in the eastern Irish Sea with vessels from Belgium, Ireland, and the UK. This fishery mainly catches sole with important bycatches of plaice, rays, brill, turbot, anglerfish, and cod. The fishing effort of the Belgian beam trawl fleet varies in response to the catch rates of sole in the Irish Sea relative to catch rates in other areas in which the fleet operates. Fishing effort peaked in the late 1980s following a series of strong year classes of sole, but is presently only about 60% of the peak value. The other gears used to catch demersal species are gillnets and tanglenets, notably by inshore boats targeting cod, bass, grey mullet, sole, and plaice, and the bottom VHVO trawl targeting hake. The main pelagic fishery in the Irish Sea is for herring. In recent years, it has been predominantly operated by one pair of trawlers from Northern Ireland. The size of this fleet has declined to a very low level in recent years. There are also a number of inshore fisheries in the Irish Sea that target stocks not currently assessed by ICES. These include pot fisheries for crab, lobster, and whelk, hydraulic dredge fisheries for razor clams, and dredge fisheries for scallops. Decommissioning at the end of 2003 permanently removed 19 out of 237 UK demersal vessels operating in the Irish Sea, representing a loss of 8% of the fleet by number and 9.3% by tonnage. Of these vessels, 13 were vessels that had used demersal trawls with mesh size >=100 mm and had more than 5% cod in their reported landings. The previous round of decommissioning in 2001 removed 29 UK(NI) Nephrops and whitefish vessels and 4 UK(E&W) vessels registered in Irish Sea ports at the end of 2001. Of these, 13 were vessels that used demersal trawls with mesh size >=100 mm and had more than 5% cod in their reported landings. The Irish fleet has also declined in numbers in recent years although there has been some modernization particularly since 2000, whereby several large newer vessels joined the fleet. More recently there has also been an Irish decommissioning scheme, whereby around 40 fishing vessels (~6000 GT, 18 000 kW) have been permanently withdrawn from the Irish fishing fleet and removed from the Register of Sea Fishing Vessels in 2005 and 2006. Several of these vessels have a track record of fishing in Division VIIa. Fishing effort in the semi-pelagic effort increased rapidly between the early 1980s and early 1990s before decreasing somewhat in the mid-1990s. Fishing effort in the England and Wales otter trawl vessels longer than 12 m declined rapidly after 1989, and from 1999 to 2004 was less than 25% of the effort reported in the 1980s. There has been a declining trend in fishing effort for Northern Irish otter trawlers also since the early 1990s. Fishing effort for Irish otter trawlers has declined in recent years as many vessels switched from targeting roundfish to Nephrops. Recent fishing effort trends Within the gear and mesh categories 4A (trawls, seines, etc., > 100 mm) and 4E (trawls, seines, etc., 70 to 99 mm) gears in the Irish Sea, there is a range of fishing gears of a quite different design. Demersal trawls in the 4A category include a variety of single- and multiple-rig otter trawls used for gadoids, rays, and other demersal fish, and semi-pelagic (mid-water) trawls that have been used extensively in the deeper waters of the Irish Sea to target hake, whiting, cod, and haddock since the 1980s. Category 4E includes single-rig and multiple-rig Nephrops trawls, and whitefish trawls targeting species such as plaice and whiting where catch composition rules permit this mesh size. The change in mesh


size regulations in 2000, requiring the use of 100 mm mesh for vessels targeting species such as cod, resulted in a change in the distribution of effort between mesh bands. The nominal effort trends in kW-days for Division VIIa given by STECF–SGRST and updated by ICES in 2006 are given in Table 5.3.2.5. In the case of UK vessels, the figures for the gear types sum to the aggregated STECF figures for 2000–2004. Figures for Belgium have been revised slightly. Major revisions were supplied by Ireland. Specifically, effort data by mesh band for Ireland were not available for 2000–2002, and the figures given by STECF for these years may not be accurate or complete. The majority of nominal effort is in the gear grouping for otter trawls with mesh sizes between 70 and 99 mm. Most of the effort in this mesh band is attributable to Nephrops trawlers, but it also includes vessels targeting plaice, whiting, or other species where the catch-composition rules permit 70 to 99 mm trawls. These are included in the “whitefish otter trawl” category, although the distinction between Nephrops trawls and whitefish trawls using 70 to 99 mm mesh is blurred because many vessels use gears optimized to catch Nephrops with a whitefish bycatch. The more restricted days-at-sea allowances for 4A (100 mm+ ) otter trawls has resulted in some vessels returning to 70 to 99 mm trawls to obtain more days per month. A number of UK(NI) vessels switch between semi-pelagic trawls and twin-rig Nephrops trawls according to fishing opportunities, including access to the cod spawning closure where there is a derogation for Nephrops vessels. The effort of the two series tends to vary in opposite directions. The fishing effort for UK 4A gear types has declined in the last few years in Division VIIa. Specifically, fishing effort of mid-water whitefish trawlers has declined by 50% between 2003 and 2005, and effort of Irish otter trawlers (100 mm+) has declined by over 80% in the same period (Figure 5.3.2.15). Fishing effort of single-rig Nephrops trawls has declined significantly since 2001. The combined effort of towed gears and static gears (gillnets and longlines) has declined since 2001. Taking Irish and Belgian fleets into account, an almost threefold decline in international effort of 100 mm+ demersal trawls is evident between 2003 and 2006, whilst otter trawls in the 70 to 99 mm mesh band have slightly increased their effort over this period. Beam trawl effort declined slightly between 2000 and 2002, and gillnet effort has halved over these three years. Although the trends in kW-days are indicative of recent trends in fleet activities in recent years, the relationship with fishing mortality will be affected by changes in the amount of fishing per day at sea, technological improvements, and changes in species targeting and fishing practices resulting from management restrictions and changing fish availability. An analysis of catchability (F generated per unit of effort) will require more highly resolved data, (both spatially and temporally), accurate catch and effort data for suitably disaggregated fleet/gear combinations, and sufficiently accurate assessment estimates of F. Recent trends in F are very poorly determined for most of the stocks assessed by WGNSDS. However, very large apparent changes in mortality (e.g. the large decline in estimates of F in Division VIa haddock, mirroring a similar large decline in F estimates for the North Sea haddock stock in recent years) should be reflected in recent trends in kW-days in fleets targeting the species. Fisheries interactions in the Irish Sea Demersal fisheries in the area are mixed fisheries, with many stocks exploited together in various combinations in different fisheries. In these cases management advice must consider both the state of individual stocks and their simultaneous exploitation in demersal fisheries. Stocks in the poorest condition, particularly the critical stocks, necessarily become the overriding concern for the management of mixed fisheries where these stocks are exploited either as a targeted species or as a bycatch. Four main fishery units can be described in the Irish Sea: these are Nephrops otter trawlers, roundfish otter trawlers, semi-pelagic trawlers, and beam trawlers. As trends in stocks of various species are generally not in synchrony, advice provided on the basis of the status of individual species may result in advised fishing mortalities for a group of co-harvested species that cannot be realized simultaneously within the context of mixed fisheries. Stocks in need of special conservation efforts, such as recovery plans, present particularly difficult challenges. For instance, the reduction of fishing mortality (and effort) required for cod makes it very unlikely that TACs for healthier stocks in the mixed fisheries could be taken. The needs of the stock(s) under recovery plans could be met most directly by setting the TACs for all species in mixed fisheries to correspond to the fishing mortality intended for the species under recovery plans, which would result in large foregone yields in many healthier stocks. The foregone yield could be reduced somewhat if effort could be adjusted on a fleet-by-fleet basis to comply with the total fishing mortality in the proposed recovery plan, while allowing as much harvesting of other species as possible. However, such an approach requires reliable information on the catch-at-age for all species in all fisheries, and is still likely to leave substantial potential harvestable biomass of several species unavailable to any fishery.


Possibly the strongest mixed fishery interaction in the Irish Sea is between the Nephrops fishery and the whiting stock. Discard estimates for fleets targeting Nephrops are incomplete and considered imprecise, but demonstrate that the selectivity of Nephrops trawls for whiting remains relatively poor despite the obligatory use of square-mesh panels for vessels targeting Nephrops with a 70 mm codend mesh since 1994. ICES points out that in addition to effort restrictions, further technical measures (e.g. increased codend and square-mesh panel mesh sizes, separator panels, and fixed grids) should be investigated and this may substantially reduce bycatch and discarding of whiting in this Nephrops fishery. The cod fishery was traditionally carried out by otter trawlers targeting spawning cod in spring and juvenile cod in autumn and winter. Activities of these vessels have decreased, whilst a fishery for cod and haddock using large pelagic trawls increased substantially during the 1990s. Cod are also taken as a bycatch in the Nephrops-directed fishery. Although discard estimates for cod in the Irish Sea are not available, discard rates are not thought to be substantial. However, misreporting and underreporting of cod is thought to occur in some Division VIIa fisheries. Estimates of misreporting for some nations are included in the assessment, but the scientific advice for zero catch of the cod stock requires that the practice be terminated. The extent to which the stocks are taken in the same fisheries cannot be quantified on the basis of the available data. The existing information suggests that the stocks are caught together to a high (H), medium (M), low (L) extent, or not at all (0), as indicated in Table 5.3.2.3. The information in the table relates to catches so a ‘high’ linkage can relate to high landings for two species in one fishery, but also to cases where the bycatch of a stock taken in a mixed fishery is discarded.

ICES

Adv

ice

2008

, Boo

k 5

19

Tab

le 5

.3.2

.1

Stoc

k in

tera

ctio

ns –

Cel

tic S

ea, S

outh

wes

t of I

rela

nd, a

nd W

este

rn C

hann

el.

Stoc

k in

tera

ctio

n ta

ble

Anglerfish budegassa VIIb-k, VIIIabd

Anglerfish piscatorius VIIb-k, VIIIabd

Cod VIIe-k

Haddock VIIb-k

Hake Northern

Herring Celtic Sea and Division VIIj

Herring VIa(S) and VIIbc

Horse Mackerel Southern

Horse Mackerel Western

Mackerel North East Atlantic

Megrim VII, VIIIabd

Nephrops Area L: VIIbcjk

Nephrops Area M: VIIfgh+VIIa

Plaice VIIbc

Plaice VIIe

Plaice VIIfg

Plaice VIIhjk

Sole VIIbc

Sole VIIe

Sole VIIfg

Sole VIIhjk

Sprat VIIde

Whiting VIIe-k

Seabass

Skates and rays

Pelagic and migratory sharks

Demersal sharks

Angl

erfis

h bu

dega

ssa

VIIb

-k, V

IIIab

dH

LL

M0

00

00

MM

LL

LL

LL

LL

LL

HH

Angl

erfis

h pi

scat

oriu

s VI

Ib-k

, VIII

abd

TL

LM

00

00

0M

MM

LL

LL

LL

LL

LH

H

Cod

VIIe

-kT

TH

L0

00

00

LL

M0

LM

L0

LL

L0

H/M

HL

H

Had

dock

VIIb

-k

TT

TL

00

00

0L

MM

LL

LL

LL

LL

0H

0H

LH

Hak

e N

orth

ern

TT

T0

00

00

MM

LL

0L

L0

LL

HL

H

Her

ring

Cel

tic S

ea a

nd D

ivis

ion

VIIj

NN

NN

N0

00

00

00

00

00

00

00

00

00

Her

ring

VIa(

S) a

nd V

IIbc

NN

NN

NN

00

00

00

00

00

00

00

00

00

Hor

se M

acke

rel S

outh

ern

NN

NN

NN

N0

H0

00

00

00

00

00

00

00

0

Hor

se M

acke

rel W

este

rnN

NN

NN

NN

NH

00

00

00

00

00

00

00

00

Mac

kere

l Nor

th E

ast A

tlant

icN

NN

NN

NN

00

00

00

00

00

00

00

00

Meg

rim V

II, V

IIIab

dT,

BT

T, B

TT

TN

NN

NN

HM

LL

LL

LL

HH

Nep

hrop

s Ar

ea L

: VIIb

cjk

NT

NT

NT

NT

NT

NN

NN

NN

T0

L0

0L

L0

0L

0M

LL

Nep

hrop

s Ar

ea M

: VIIf

gh+V

IIaN

TN

TN

TN

TN

TN

NN

NN

NT

N0

00

L0

0L

L0

ML

L

Plai

ce V

IIbc

NN

NN

NN

NT

N0

00

L0

00

0L

0H

M

Plai

ce V

IIeO

T, B

TO

T, B

TO

T, B

TN

NN

NN

NN

NN

00

0H

00

0L

HM

Plai

ce V

IIfg

OT,

BT

OT,

BT

OT,

BT

OT,

BT

NN

NN

NN

NN

NN

00

0H

00

LH

M

Plai

ce V

IIhjk

BT,

OT

NN

NN

NN

TN

NN

N0

00

L0

L0

HM

Sole

VIIb

cN

NN

NN

NN

NN

NN

00

00

L0

HM

Sole

VIIe

BT, O

TB

T, O

TB

T, O

TN

NN

NN

NN

NN

BT,

OT

NN

N0

00

LH

M

Sole

VIIf

gBT

, OT

BT,

OT

BT,

OT

BT, O

TN

NN

NN

NBT

NN

TN

NBT

, OT

NN

N0

0L

HM

Sole

VIIh

jkB

T, O

TN

NN

NN

NN

NN

NT,

BT

NN

N0

L0

HM

Spra

t VIId

eN

NN

NN

NN

NN

NN

NN

NN

NN

0

Whi

ting

VIIe

-kT

TT

TN

NN

NN

NT

NT

NN

BT, O

TN

NBT

, OT

0H

H

Seab

ass

NN

NN

N0

Skat

es a

nd ra

ysBT

, OT

BT,

OT

BT,

OT

BT, O

TB

T, O

TN

NN

NN

BT, O

TN

TN

TBT

, OT

BT,

OT

BT, O

TBT

, OT

BT,

OT

BT, O

TB

T, O

TN

BT,

OT

H

Pela

gic

and

mig

rato

ry s

hark

sBT

, OT

BT,

OT

BT,

OT

BT, O

TB

T, O

TN

NN

NN

BT, O

TBT

, OT

BT,

OT

BT, O

TBT

, OT

BT,

OT

BT, O

TB

T, O

TN

BT,

OT

Dem

ersa

l sha

rks

BT, O

TB

T, O

TB

T, O

TBT

, OT

BT,

OT

NN

NN

NBT

, OT

NT

NT

BT, O

TB

T, O

TBT

, OT

BT, O

TB

T, O

TBT

, OT

BT,

OT

NB

T,O

TBT

,OT

H; t

he s

tock

s ar

e ta

ken

toge

ther

in m

ost f

ishe

ries

whe

re th

ey a

re ta

ken

and

thei

r fis

herie

s lin

kage

is th

eref

ore

high

; M: t

he s

tock

s ar

e ta

ken

toge

ther

in s

ome

but n

ot a

ll im

porta

nt fi

sher

ies

and

thei

r fis

herie

s lin

kage

is th

eref

ore

med

ium

; L: t

he s

tock

s T:

Tra

wl;

BT: B

eam

traw

l; O

T: O

tter t

raw

l; N

T: N

ephr

ops

traw

l; N

: non

e



IC

ES A

dvic

e 20

08, B

ook

5 20T

able

5.3

.2.2

St

ock

inte

ract

ions

Wes

t of S

cotla

nd.

A

ngle

rfis

h IV

+VI

Meg

rim

C

od V

Ia

Had

dock

VIa

W

hitin

g V

Ia

Nep

hrop

s VIa

Sai

the

IV+V

IaH

erri

ng V

Ia

NE

A

Mac

kere

l D

eepw

ater

fis

h A

ngle

rfis

h IV

+VI

O

TB, G

ND

O

TB

OTB

O

TB

NEP

OTB

O

TB

PTM

PT

M

OTB

D

eep,

G

ND

M

egri

m

Stro

ng

O

TB

OTB

O

TB

NEP

OTB

O

TB

PTM

O

TB D

eep

OTB

Dee

p C

od V

ia

Wea

k W

eak

O

TB, P

T O

TB, P

T O

TB,

NEP

OTB

O

TB,

OTB

D

eep,

PT

PTM

PT

M

OTB

Dee

p

Had

dock

Via

W

eak

Wea

k St

rong

OTB

, PT

NEP

OTB

O

TB, P

T PT

M

PTM

O

TB D

eep

Whi

ting

Via

W

eak

Med

ium

St

rong

St

rong

NEP

OTB

O

TB

PTM

PT

M

OTB

Dee

p N

ephr

ops V

ia

Med

ium

M

ediu

m

Med

ium

St

rong

St

rong

OTB

PT

M

PTM

O

TB D

eep

Saith

e II

Ia+I

V+V

ia

Wea

k W

eak

Med

ium

M

ediu

m

Wea

k W

eak

PT

M

PTM

O

TB D

eep

Her

ring

Via

0

0 0

0 0

0 0

PT

M

OTB

Dee

p N

EA

Mac

kere

l 0

0 0

0 0

0 W

eak

Wea

k

OTB

Dee

p D

eepw

ater

fish

St

rong

M

ediu

m

Wea

k W

eak

0 W

eak

Wea

k 0

0

Inte

ract

ion

W

eak

Wea

k

OT

B D

eep

Otte

r Tra

wls

in d

eepw

ater

PT

M

Pela

gic

Mid

wat

er T

raw

l

Med

ium

m

ediu

m

O

TB

Nep

O

tter T

raw

l Nep

hrop

s dire

cted

PT

Pa

ir Tr

awl

Stro

ng

stro

ng

G

ND

G

illne

ts d

emer

sal &

dee

pwat

er

20 ICES Advice 2008, Book 5


Table 5.3.2.3 Technical interactions in the Irish Sea.

Technical Interactions MatrixCod in

Division VIIa

Haddock VIIa

NephropsFU 15 &

FU 14

Plaice VIIa

Sole VIIa

Whiting VIIa

Rays VIIa

Herring VIIaN Scallops WhelksRazor

Fish

Cod in Division VIIa H M M M M L 0 0 0 0

Haddock VIIa

White fish

trawl, Semi-

pelagic trawl,

Seine-net

M M L M L 0 0 0 0

Nephrops FU 15 & FU 14 Nephrops

trawl fishery

Nephropstrawl

fishery M L H L 0 0 0 0

Plaice VIIa

Flatfish beam trawl,

Nephrops trawl

Nephropstrawl

Nephropstrawl H L M 0 0 0 0

Sole VIIa

Flat fish beam trawl,

Nephrops trawl

Flat fish beam trawl

Nephropstrawl

Flatfish beam trawl

L M 0 0 0 0

Whiting VIIa

Semi-pelagic trawl,

Nephrops trawl, White

fish trawl

White fish

trawl, Semi-

pelagic trawl,

Seine-net

Nephropstrawl

Nephropstrawl

Beam trawl L 0 0 0 0

Rays VIIa

Ray otter and beam

trawl fishery

Ray otter and beam

trawl fishery

Nephropstrawl

Beam trawl

Beam trawl

Ray otter and

beam trawl

fishery

0 0 0 0

Herring VIIaN None None None None None None None 0 0 0 Scallops None None None None None None None None 0 0 Whelks None None None None None None None None None 0

Razor Fish None None None None None None None None None None

ICES

Adv

ice

2008

, Boo

k 5

22Tab

le 5

.3.2

.4

Sing

le-s

tock

exp

loita

tion

boun

darie

s and

crit

ical

stoc

ks in

the

Cel

tic S

eas e

core

gion

.

Stat

e of

the

stoc

k

ICE

S co

nsid

erat

ions

in r

elat

ion

to si

ngle

-sto

ck e

xplo

itatio

n bo

unda

ries

Stoc

k

Spaw

ning

bio

mas

s in

rela

tion

to

prec

autio

nary

lim

its

Fish

ing

mor

talit

y in

rel

atio

n to

pr

ecau

tiona

ry

limits

Fish

ing

mor

talit

y in

re

latio

n to

hig

h lo

ng-

term

yie

ld

In r

elat

ion

to a

gree

d m

anag

emen

t pla

n in

rel

atio

n to

hig

h lo

ng-t

erm

yie

ld

in r

elat

ion

to p

reca

utio

nary

lim

its

Upp

er li

mit

corr

espo

ndin

g to

sing

le-

stoc

k ex

ploi

tatio

n bo

unda

ry –

Ton

nes o

r ef

fort

in 2

009

Ang

lerfi

sh in

Div

ision

s V

IIb–k

and

VIII

a,b

(L. p

iscat

oriu

s and

L.

bud

egas

sa)

No

new

ass

essm

ent

Sam

e ad

vice

as l

ast y

ear

TA

C <

33

000

t

Ang

lerfi

sh in

Div

ision

III

a, S

ubar

ea IV

, and

Su

bare

a V

I

No

new

ass

essm

ent

Sam

e ad

vice

as l

ast y

ear

N

o in

crea

se in

eff

ort

Cod

in D

ivis

ion

VIa

(W

est o

f Sco

tland

) R

educ

ed re

prod

uctiv

e ca

paci

ty

Unk

now

n U

nkno

wn

ICES

is n

ot in

a

posi

tion

to g

ive

quan

titat

ive

fore

cast

s.

Unk

now

n G

iven

the

low

SSB

and

low

recr

uitm

ents

in re

cent

ye

ars,

it is

not

pos

sibl

e to

iden

tify

any

non-

zero

ca

tch

whi

ch w

ill b

e co

mpa

tible

with

the

prec

autio

nary

app

roac

h..

0

Cod

in D

ivisi

on V

Ib

(Roc

kall)

In

suffi

cien

t inf

orm

atio

n to

eva

luat

e st

ock

tren

ds

N

o ad

vice

Cod

in D

ivisi

on V

IIa

Red

uced

repr

oduc

tive

capa

city

H

arve

sted

un

sust

aina

bly

Ove

rfis

hed

ICES

is n

ot in

a

posi

tion

to g

ive

quan

titat

ive

fore

cast

s

F is

abo

ve F

0.1 –F

max

G

iven

the

low

stoc

k si

ze a

nd re

cent

poo

r re

crui

tmen

t, it

is n

ot p

ossi

ble

to id

entif

y an

y no

n-ze

ro c

atch

that

wou

ld b

e co

mpa

tible

with

the

prec

autio

nary

app

roac

h.

0

Cod

in D

ivisi

ons

VIIe

-k

Incr

ease

d ris

k H

arve

sted

su

stai

nabl

y O

verf

ishe

d N

ot a

pplic

able

F

is a

bove

Fm

ax

50%

redu

ctio

n in

fish

ing

mor

talit

y w

hich

is

asso

ciat

ed w

ith la

ndin

gs in

200

9 of

260

0 t a

nd th

e SS

B is

exp

ecte

d to

reac

h B

pa in

201

0. T

his f

ishi

ng

mor

talit

y al

so c

orre

spon

ds to

hig

h lo

ng-te

rm y

ield

an

d lo

w ri

sk o

f sto

ck d

eple

tion.

<260

0 t

Had

dock

in D

ivis

ion

VIa

(Wes

t of S

cotla

nd)

Incr

ease

d ris

k In

crea

sed

risk

Ove

rfis

hed

Not

app

licab

le

F is

abo

ve F

max

C

losu

re o

f the

fish

ery

in 2

009

and

a re

cove

ry p

lan

shou

ld b

e de

velo

ped

and

impl

emen

ted

as a

pr

ereq

uisi

te to

reop

enin

g th

e fis

hery

.

0

Had

dock

in D

ivisi

on

VIb

(Roc

kall)

Fu

ll re

prod

uctiv

e ca

paci

ty

Har

vest

ed

sust

aina

bly

Ove

rfis

hed

Not

app

licab

le

F is

abo

ve F

max

Fi

shin

g m

orta

lity

shou

ld

be

less

th

an

F pa,

corr

espo

ndin

g to

tota

l cat

ches

less

than

974

0 t i

n 20

09 a

nd la

ndin

gs o

f 647

0 t i

n 20

09.

Ther

e is

no

long

-term

gai

n in

yie

ld to

incr

ease

fis

hing

mor

talit

y. IC

ES th

eref

ore

reco

mm

ends

to

limit

catc

hes i

n 20

09 to

no

mor

e th

an 6

490

t with

la

ndin

gs o

f 433

0 t.

< 43

30 t

Had

dock

VII

a U

ndef

ined

U

ndef

ined

U

ndef

ined

N

ot a

pplic

able

U

nkno

wn

Fish

ing

effo

rt sh

ould

not

be

allo

wed

to in

crea

se.

No

incr

ease

in e

ffor

t

Had

dock

in D

ivis

ions

V

IIb–

k U

ndef

ined

U

ndef

ined

U

ndef

ined

Sa

me

advi

ce a

s las

t yea

r

No

incr

ease

in e

ffor

t

Her

ring

in V

Ia so

uth

and

VIIb

,c

No

new

ass

essm

ent

Sam

e ad

vice

as l

ast y

ear

No

fishi

ng w

ithou

t a

rebu

ildin

g pl

an


ICES

Adv

ice

2008

, Boo

k 5

23

Stat

e of

the

stoc

k

ICE

S co

nsid

erat

ions

in r

elat

ion

to si

ngle

-sto

ck e

xplo

itatio

n bo

unda

ries

Stoc

k

Spaw

ning

bio

mas

s in

rela

tion

to

prec

autio

nary

lim

its

Fish

ing

mor

talit

y in

rel

atio

n to

pr

ecau

tiona

ry

limits

Fish

ing

mor

talit

y in

re

latio

n to

hig

h lo

ng-

term

yie

ld

In r

elat

ion

to a

gree

d m

anag

emen

t pla

n in

rel

atio

n to

hig

h lo

ng-t

erm

yie

ld

in r

elat

ion

to p

reca

utio

nary

lim

its

Upp

er li

mit

corr

espo

ndin

g to

sing

le-

stoc

k ex

ploi

tatio

n bo

unda

ry –

Ton

nes o

r ef

fort

in 2

009

Her

ring

in D

ivisi

on V

Ia

Nor

th

Und

efin

ed

Und

efin

ed

Ove

rfis

hed

Fish

ing

acco

rdin

g to

th

e pr

opos

ed

man

agem

ent p

lan

impl

y ca

tche

s up

to

13 0

00 t

F in

the

rang

e of

the

targ

et m

orta

lity

of th

e pr

opos

ed m

anag

emen

t pl

an is

exp

ecte

d to

gi

ve a

hig

h lo

ng-te

rm

yiel

d an

d a

low

risk

of

stoc

k de

plet

ion.

Prec

autio

nary

refe

renc

e po

ints

for f

ishi

ng

mor

talit

y ha

ve n

ot b

een

defin

ed fo

r thi

s sto

ck.

Man

agem

ent m

easu

re sh

ould

hav

e a

high

pr

obab

ility

of a

void

ing

Blim

.

< 13

000

t

Celti

c se

a an

d D

ivisi

on

VIIj

her

ring

U

ncer

tain

, but

like

ly a

t ris

k of

redu

ced

repr

oduc

tive

capa

city

Unk

now

n U

nkno

wn

Not

app

licab

le

Unk

now

n N

o ta

rget

ed fi

shin

g sh

ould

be

allo

wed

unt

il a

rebu

ildin

g pl

an is

in p

lace

. R

educ

ed c

atch

es

Iris

h Se

a he

rrin

g (D

ivis

ion

VII

a N

) N

o ne

w a

sses

smen

t

Sam

e ad

vice

as l

ast y

ear

<4

4 00

t

Meg

rim in

Div

isio

ns

VII

b,c,

e-k

and

VII

Ia,b

,d (L

. w

hiffi

agon

is)

No

new

ass

essm

ent

Sa

me

advi

ce a

s las

t yea

r

<13

000

t

Meg

rim in

Sub

area

VI

(Wes

t of S

cotla

nd a

nd

Rock

all)

No

new

ass

essm

ent

Sa

me

advi

ce a

s las

t yea

r

< 1

400

t

Neph

rops

in D

ivisi

ons

VIIa

FU

14

Unk

now

n U

nkno

wn

Unk

now

n N

ot a

pplic

able

U

nkno

wn

No

incr

ease

in e

ffort

and

catc

hes (

2007

) N

o in

crea

se in

eff

ort

and

<1 0

00 t

Neph

rops

in D

ivisi

ons

VIIa

FU

15

Unk

now

n U

nkno

wn

Unk

now

n N

ot a

pplic

able

U

nkno

wn

No

incr

ease

in e

ffort

and

catc

hes (

2007

) N

o in

crea

se in

eff

ort

and

< 8

500

t Ne

phro

ps in

Div

ision

V

Ia, N

orth

Min

ch

(FU

11)

Unk

now

n U

nkno

wn

Unk

now

n N

ot a

pplic

able

U

nkno

wn

No

incr

ease

in e

ffor

t and

rece

nt a

vera

ge c

atch

es

(200

6-20

07)

No

incr

ease

in e

ffor

t an

d <

4 1

00 t

Neph

rops

in D

ivisi

on

VIa

, Sou

th M

inch

(F

U12

)

Unk

now

n U

nkno

wn

Unk

now

n N

ot a

pplic

able

U

nkno

wn

No

incr

ease

in e

ffor

t and

rece

nt a

vera

ge c

atch

es

(200

6-20

07)

No

incr

ease

in e

ffor

t an

d <

5 0

00 t

Neph

rops

in D

ivisi

on

VIa

, Firt

h of

Cly

de

(FU

13)

Unk

now

n U

nkno

wn

Unk

now

n N

ot a

pplic

able

U

nkno

wn

No

incr

ease

in e

ffor

t and

rece

nt a

vera

ge c

atch

es

(200

6-20

07)

No

incr

ease

in e

ffor

t an

d <

5 7

00 t

Neph

rops

in D

ivisi

on

VIa

“ot

her a

reas

”

Unk

now

n U

nkno

wn

Unk

now

n N

ot a

pplic

able

U

nkno

wn

No

incr

ease

in e

ffor

t and

rece

nt a

vera

ge c

atch

es

(200

5-20

07)

No

incr

ease

in e

ffor

t an

d <

300

t N

ephr

ops i

n Su

b-ar

ea

VII

: Por

cupi

ne b

ank

(FU

16)

Unk

now

n U

nkno

wn

Unk

now

n N

ot a

pplic

able

U

nkno

wn

No

incr

ease

in e

ffor

t and

ave

rage

cat

ches

bel

ow

the

leve

l bef

ore

the

expa

nsio

n of

the

fishe

ries

(200

0-20

03)

No

incr

ease

in e

ffor

t an

d <

1 00

0 t

Nep

hrop

s in

Sub-

area

V

II: A

ran

Gro

unds

(F

U 1

7)

Unk

now

n U

nkno

wn

Unk

now

n N

ot a

pplic

able

U

nkno

wn

No

incr

ease

in e

ffort

and

land

ings

(200

7)

No

incr

ease

in e

ffor

t an

d <

900

t

Nep

hrop

s in

Sub-

area

V

II: I

rela

nd S

W a

nd

SE c

oast

(FU

19)

Unk

now

n U

nkno

wn

Unk

now

n N

ot a

pplic

able

U

nkno

wn

No

incr

ease

in e

ffort

and

land

ings

(200

7)

No

incr

ease

in e

ffor

t an

d <

800

t


ICES

Adv

ice

2008

, Boo

k 5

24

Stat

e of

the

stoc

k

ICE

S co

nsid

erat

ions

in r

elat

ion

to si

ngle

-sto

ck e

xplo

itatio

n bo

unda

ries

Stoc

k

Spaw

ning

bio

mas

s in

rela

tion

to

prec

autio

nary

lim

its

Fish

ing

mor

talit

y in

rel

atio

n to

pr

ecau

tiona

ry

limits

Fish

ing

mor

talit

y in

re

latio

n to

hig

h lo

ng-

term

yie

ld

In r

elat

ion

to a

gree

d m

anag

emen

t pla

n in

rel

atio

n to

hig

h lo

ng-t

erm

yie

ld

in r

elat

ion

to p

reca

utio

nary

lim

its

Upp

er li

mit

corr

espo

ndin

g to

sing

le-

stoc

k ex

ploi

tatio

n bo

unda

ry –

Ton

nes o

r ef

fort

in 2

009

Nep

hrop

s in

Sub-

area

V

II:C

eltic

Sea

(FU

20-

22)

Unk

now

n U

nkno

wn

Unk

now

n N

ot a

pplic

able

U

nkno

wn

No

incr

ease

in e

ffort

and

land

ings

(200

7)

No

incr

ease

in e

ffor

t an

d <

5300

t

Neph

rops

in D

ivisi

on

VII

“oth

er a

reas

”

Unk

now

n U

nkno

wn

Unk

now

n N

ot a

pplic

able

U

nkno

wn

No

incr

ease

in e

ffor

t and

rece

nt a

vera

ge c

atch

es

(200

3-20

07)

No

incr

ease

in e

ffor

t an

d <

200

t N

orw

ay p

out W

est o

f Sc

otla

nd

Insu

ffici

ent i

nfor

mat

ion

to e

valu

ate

stoc

k tr

ends

No

advi

ce

Plai

ce in

VII

a (I

rish

Sea)

Fu

ll re

prod

uctiv

e ca

paci

ty

Har

vest

ed

sust

aina

bly

Und

erfis

hed

Not

app

licab

le

F is

bel

ow F

0.1.

Fish

ing

at F

0.1

corr

espo

nds t

o la

ndin

gs in

200

9 of

14

30 t.

Fish

ing

mor

talit

y sh

ould

be

kept

bel

ow F

pa (0

.45)

. Th

is c

orre

spon

ds to

cat

ches

of

less

than

396

0 t i

n 20

09 a

nd w

ill m

aint

ain

SSB

abo

ve B

pa in

201

0.

< 14

30 t

Plai

ce W

est o

f Ire

land

(D

ivis

ion

VII

b,c)

N

o ne

w a

sses

smen

t

Sam

e ad

vice

as l

ast y

ear

< 40

t

Plai

ce in

Div

ision

VIIe

(W

este

rn C

hann

el)

No

new

ass

essm

ent

Sa

me

advi

ce a

s las

t yea

r Su

bsta

ntia

l red

uctio

n in

ca

tch

Plai

ce in

the

Cel

tic S

ea

(Div

ision

s VIIf

and

g)

Red

uced

repr

oduc

tive

capa

city

U

ndef

ined

O

verf

ishe

d N

ot a

pplic

able

F

is a

bove

F0.

1 –

F max

A

75%

redu

ctio

n in

F is

nee

ded

to in

crea

se S

SB to

ar

ound

Bpa

in 2

010.

Thi

s cor

resp

onds

to la

ndin

gs

of le

ss th

an 1

70 t

in 2

009.

< 17

0 t

Plai

ce S

outh

wes

t of

Irel

and

(VII

h-k)

N

o ne

w a

sses

smen

t

Sam

e ad

vice

as l

ast y

ear

< 17

7 t

Sand

eel i

n D

ivisi

on V

IaIn

suffi

cien

t inf

orm

atio

n to

eva

luat

e st

ock

tren

ds

N

o ad

vice

So

le V

IIa

Red

uced

repr

oduc

tive

capa

city

A

t ris

k of

har

vest

ed

unsu

stai

nabl

y O

verf

ishe

d N

ot a

pplic

able

F

is a

bove

F0.

1

Giv

en th

e lo

w S

SB a

nd lo

w re

crui

tmen

t sin

ce

2000

, it i

s not

pos

sibl

e to

iden

tify

any

non-

zero

ca

tch

whi

ch w

ill b

e co

mpa

tible

with

the

prec

autio

nary

app

roac

h

0

Sole

Wes

t of I

rela

nd

(Div

isio

n V

IIb,

c)

No

new

ass

essm

ent

Sa

me

advi

ce a

s las

t yea

r. <

50 t

Sole

in D

ivisi

on V

IIe

(Wes

tern

Cha

nnel

) In

crea

sed

risk

Har

vest

ed

unsu

stai

nabl

y O

verf

ishe

d Th

e m

ulti-

annu

al p

lan

impl

ies a

20%

re

duct

ion

in F

co

mpa

red

to a

vera

ge

F(03

–05)

whi

ch

corr

espo

nds t

o la

ndin

gs o

f 650

t. T

his

is a

15%

redu

ctio

n in

th

e TA

C c

ompa

red

to

2008

.

F is

abo

ve F

0.1

Con

side

ring

that

the

man

agem

ent

plan

has

not

be

en e

valu

ated

by

ICES

, IC

ES a

dvis

es o

n th

e ba

sis

of

prec

autio

nary

lim

its.

Reb

uild

ing

the

stoc

k ab

ove

Bpa

in

just

one

yea

r w

ould

req

uire

tha

t fis

hing

mor

talit

y is

redu

ced

by 7

0%.

This

wou

ld

corr

espo

nd t

o la

ndin

gs o

f ar

ound

320

ton

nes

in

2009

.

< 32

0 t

Sole

in th

e Ce

ltic

Sea

(Div

ision

s VIIf

and

g)

Full

repr

oduc

tive

capa

city

H

arve

sted

su

stai

nabl

y O

vere

xplo

ited

Not

app

licab

le

F200

7 is

abo

ve F

0.1–

F max

.

F sh

ould

be

kept

bel

ow F

pa. T

his c

orre

spon

ds to

la

ndin

gs o

f les

s tha

n 10

90 to

nnes

in 2

009.

Th

ere

is n

o lo

ng-te

rm g

ain

in y

ield

to in

crea

se

fishi

ng m

orta

lity.

ICES

ther

efor

e re

com

men

ds to

lim

it la

ndin

gs in

200

9 to

no

mor

e th

an 9

40 t.

< 94

0 t


ICES

Adv

ice

2008

, Boo

k 5

25

Stat

e of

the

stoc

k

ICE

S co

nsid

erat

ions

in r

elat

ion

to si

ngle

-sto

ck e

xplo

itatio

n bo

unda

ries

Stoc

k

Spaw

ning

bio

mas

s in

rela

tion

to

prec

autio

nary

lim

its

Fish

ing

mor

talit

y in

rel

atio

n to

pr

ecau

tiona

ry

limits

Fish

ing

mor

talit

y in

re

latio

n to

hig

h lo

ng-

term

yie

ld

In r

elat

ion

to a

gree

d m

anag

emen

t pla

n in

rel

atio

n to

hig

h lo

ng-t

erm

yie

ld

in r

elat

ion

to p

reca

utio

nary

lim

its

Upp

er li

mit

corr

espo

ndin

g to

sing

le-

stoc

k ex

ploi

tatio

n bo

unda

ry –

Ton

nes o

r ef

fort

in 2

009

Sole

Sou

thw

est o

f Ir

elan

d

(Div

isio

n V

IIh–

k)

No

new

ass

essm

ent

Sam

e ad

vice

as l

ast y

ear.

< 30

0 t

Spra

t in

divi

sions

VII

d,e

N

o ne

w a

sses

smen

t Sa

me

advi

ce a

s las

t yea

r N

o ad

vice

Whi

ting

in D

ivis

ion

VII

a N

o ne

w a

sses

smen

t

Sam

e ad

vice

as l

ast y

ear

0

Whi

ting

in D

ivisi

ons

VIIe

–k

Unk

now

n U

ndef

ined

U

nkno

wn

Not

app

licab

le

Unk

now

n Th

e cu

rren

t est

imat

es o

f fis

hing

mor

talit

y an

d SS

B

are

unce

rtain

, but

SSB

show

s a d

ecre

asin

g tre

nd

whi

le re

crui

tmen

t is l

ow. I

n or

der t

o re

vers

e th

is

trend

, IC

ES c

onsi

ders

that

fish

ing

mor

talit

y sh

ould

be

redu

ced.

How

ever

, IC

ES c

anno

t qua

ntify

the

requ

ired

redu

ctio

n in

fish

ing

mor

talit

y.

--

Whi

ting

Wes

t of

Scot

land

N

o ne

w a

sses

smen

t

Sam

e ad

vice

as l

ast y

ear

0

Whi

ting

in D

ivisi

on

VIb

(Roc

kall)

In

suffi

cien

t inf

orm

atio

n to

eva

luat

e st

ock

tren

ds

N

o ad

vice



Table 5.3.2.5 Summary of the state of the stocks and advice on elasmobranch species in the Celtic Seas eco-region.

Species Area State of stock Advice VI Depleted No target fisheries

Common skate VII Depleted No target fisheries VIa Thornback ray VIIa,f,g Stable/increasing Status quo catch

VIa Spotted ray VIIa,f,g Stable/increasing Status quo catch

VIa Stable/increasing Status quo catch Cuckoo ray VII Uncertain No advice

Blonde ray VIa, VIIa and VIIf Uncertain No advice

Undulate ray VIIj and VIIde Uncertain (but with cause for concern) No target fisheries

Smalleyed ray VIIf Stable/increasing Status quo catch VI Uncertain No advice

Sandy ray VIIb,c,h–k Stable/increasing No advice Shagreen ray VII Uncertain No advice White skate VII Severely depleted No fisheries Lesser spotted dogfish VIa and VII Stable/increasing Status quo catch

Greater spotted dogfish VII Locally stable and increasing in VIIa Status quo catch

Smooth hounds VII Stable/Increasing Status quo catch Angel shark VII Severely depleted No fisheries Identification of critical stocks The tables above identify the stocks which are outside precautionary reference points or are at critically low levels:

• Cod and whiting in Division Via; • Cod, whiting and sole in Division VIIa; • Cod in Divisions VIIe–k; • Plaice in Divisions VIIfg; • Plaice and sole in Division VIIe; • Herring in Divisions VIa south + VIIbc; • Common skate, undulate ray, white skate, and angel shark in Subarea VII.

In addition, spurdog (as advised under Widely Distributed and Migratory Stocks) is in a critical state. Advice on fisheries management Fisheries in the Celtic Seas should in 2009 be managed according to the following rules, which should be applied simultaneously. In these fisheries, there should be:

• no catch or discard of cod and whiting in Division VIa and in Division VIIa, of haddock in Division VIa and sole in Division VIIa, or of spurdog, white skate, and angel shark;

• minimal catch of common skate and undulate ray; • adherence to the recommended reduction in fishing mortality for cod in Divisions VIIe–k, whiting in

Divisions VIIe-k, plaice in Divisions VIIfg, and plaice and sole in Division VIIe; • development of rebuilding plans for herring in Divisions VIa (South) and VIIb,c and Celtic Sea herring

(VIIg,j, VIIa south). Both stocks are in need of rebuilding and fishing should not proceed without rebuilding plans;

• consideration of ICES Advice 2008 Volume 9 for deepwater stocks fished in Subareas VII and VIII; • fisheries for all other stocks that were conducted within the exploitation boundaries (see text tables

above). Furthermore, unless ways can be found to harvest species caught in mixed fisheries within precautionary limits for all those species individually, then fishing should not be permitted.


0

100000

200000

300000

400000

500000

600000

700000

1999VIIbc

2001 2003 2005 1999VIIe

2001 2003 2005 1999VIIfg

2001 2003 2005 1999VIIh

2001 2003 2005 1999VIIjk

2001 2003 2005

OTXTBNTBBSXN_A

Figure 5.3.2.1 Total effort (fishing hours) of otter trawlers (OTX), Nephrops trawlers (TBN), beam trawlers (TBB), demersal seiners (SX), and not defined gears (N_A) of Belgium, France, Ireland, and the United Kingdom operating in ICES Divisions VIIbc, VIIe, VIIfg, VIIh, and VIIjk since 1999.

0

200000

400000

600000

800000

1000000

1200000

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

N_A SX TBB TBN OTX

UKIREFRABEL

Division_2 (All)

Sum of SumOfEffort(hours)

Gear_group Year

Country

Figure 5.3.2.2 Total effort (fishing hours) in ICES Divisions VIIbc,e–k by gear type for Belgium, France, Ireland,

and the United Kingdom (not defined gears (N_A); demersal seiners (SX); beam trawlers (TBB); Nephrops trawlers (TBN) and otter trawlers (OTX)).


0

20000

40000

60000

80000

100000

120000

14000019

99

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2005

1999

2000

2001

2003

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

N_A SX TBB TBN OTX

UKIREFRA

Division_2 VIIbc


Gear_group Year

Country

Figure 5.3.2.3 Total effort (fishing hours) in ICES Divisions VIIbc by gear type for Belgium, France, Ireland, and the United Kingdom (not defined gears (N_A); demersal seiners (SX); beam trawlers (TBB); Nephrops trawlers (TBN) and otter trawlers (OTX)).

0

50000

100000

150000

200000

250000

300000

1999

2000

2001

2002

2003

2004

2005

2006

2001

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

N_A SX TBB TBN OTX

UKIREFRABEL

Division_2 VIIe


Gear_group Year

Country

Figure 5.3.2.4 Total effort (fishing hours) in ICES Division VIIe by gear group for Belgium, France, Ireland, and

the United Kingdom (not defined gears (N_A); demersal seiners (SX); beam trawlers (TBB); Nephrops trawlers (TBN) and otter trawlers (OTX)).


0

50000

100000

150000

200000

250000

300000

350000

400000

45000019

9920

0020

0120

0220

0320

0420

0520

0619

9920

0020

0120

0220

0320

0420

0520

0619

9920

0020

0120

0220

0320

0420

0520

0619

9920

0020

0120

0220

0320

0420

0520

0619

9920

0020

0120

0220

0320

0420

0520

06

N_A SX TBB TBN OTX

UKIREFRABEL

Division_2 VIIfg


Gear_group Year

Country

Figure 5.3.2.5 Total effort (fishing hours) in ICES Divisions VIIfg by gear group for Belgium, France, Ireland,

and the United Kingdom (not defined gears (N_A); demersal seiners (SX); beam trawlers (TBB); Nephrops trawlers (TBN) and otter trawlers (OTX)).

0

50000

100000

150000

200000

250000

300000

1999

2000

2001

2002

2003

2004

2005

2006

2001

2004

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

N_A SX TBB TBN OTX

UKIREFRABEL

Division_2 VIIh


Gear_group Year

Country

Figure 5.3.2.6 Total effort (fishing hours) in ICES Division VIIh by gear group for Belgium, France, Ireland, and the United Kingdom (not defined gears (N_A); demersal seiners (SX); beam trawlers (TBB); Nephrops trawlers (TBN) and otter trawlers (OTX)).


0

50000

100000

150000

200000

25000019

9920

0020

0120

0220

0320

0420

0520

0619

9920

0020

0120

0220

0320

0420

0520

0619

9920

0020

0120

0220

0320

0420

0520

0619

9920

0020

0120

0220

0320

0420

0520

0619

9920

0020

0120

0220

0320

0420

0520

06

N_A SX TBB TBN OTX

UKIREFRABEL

Division_2 VIIjk


Gear_group Year

Country

Figure 5.3.2.7 Total effort (fishing hours) in ICES Divisions VIIjk by gear group for Belgium, France, Ireland, and the United Kingdom (not defined gears (N_A); demersal seiners (SX); beam trawlers (TBB); Nephrops trawlers (TBN) and otter trawlers (OTX)).

0

200000

400000

600000

800000

1000000

1200000

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

BEL FRA IRE UK

OTXTBNTBBSXN_A

Division_2 (All)


Country Year

Gear_group

Figure 5.3.2.8 Total effort (fishing hours) in ICES Divisions VIIbc,e–k by country for otter trawlers (OTX),

Nephrops trawlers (TBN), beam trawlers (TBB), demersal seiners (SX), and not identified gear types (N_A).


0

10000

20000

30000

40000

50000

60000

70000

80000

90000

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

FRA IRE UK

OTXTBNTBBSXN_A

Division_2 VIIbc


Country Year

Gear_group

Figure 5.3.2.9 Total effort (fishing hours) in ICES Divisions VIIbc by country for otter trawlers (OTX), Nephrops

trawlers (TBN), beam trawlers (TBB), demersal seiners (SX), and not identified gear types (N_A).

0

50000

100000

150000

200000

250000

300000

350000

400000

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

BEL FRA IRE UK

OTXTBNTBBSXN_A

Division_2 VIIe


Country Year

Gear_group

Figure 5.3.2.10 Total effort (fishing hours) in ICES Division VIIe by country for otter trawlers (OTX), Nephrops



0

50000

100000

150000

200000

250000

300000

350000

400000

450000

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

BEL FRA IRE UK

OTXTBNTBBSXN_A

Division_2 VIIfg


Country Year

Gear_group

Figure 5.3.2.11 Total effort (fishing hours) in ICES Divisions VIIfg by country for otter trawlers (OTX), Nephrops


0

50000

100000

150000

200000

250000

300000

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

BEL FRA IRE UK

OTXTBNTBBSXN_A

Division_2 VIIh


Country Year

Gear_group

Figure 5.3.2.12 Total effort (fishing hours) in ICES Division VIIh by country for otter trawlers (OTX), Nephrops



0

20000

40000

60000

80000

100000

120000

140000

1999

2000

2001

2002

2003

2004

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

1999

2000

2001

2002

2003

2004

2005

2006

BEL FRA IRE UK

OTXTBNTBBSXN_A

Division_2 VIIjk


Country Year

Gear_group

Figure 5.3.2.13 Total effort (fishing hours) in ICES Divisions VIIjk by country for otter trawlers (OTX), Nephrops



Effort of fisheries in area VIa (West of Scotland)

0.00E+00

5.00E+06

1.00E+07

1.50E+07

2.00E+07

2.50E+07

3.00E+07

2000 2001 2002 2003 2004 2005 2006

Effo

rt (K

W d

ays)

LongLineGillBeamTrawl >100Trawl <100Trawl <80

Figure 5.3.2.14 Total effort (kilowatt-days) in ICES Division VIa by fishing gear and mesh size.

Effort of fisheries in area VIIa (Irish Sea)

0.00E+00

2.00E+06

4.00E+06

6.00E+06

8.00E+06

1.00E+07

1.20E+07

2000 2001 2002 2003 2004 2005 2006

Effo

rt (K

W d

ays)

LongLineGillBeamTrawl >100Trawl <100Trawl <80

Figure 5.3.2.15 Total effort (kilowatt-days) in ICES Division VIIa by fishing gear and mesh size.

ICES

Adv

ice

2008

, Boo

k 5

35

Tab

le 5

.3.2

.5

Fish

ing

effo

rt in

the

Iris

h Se

a of

nat

iona

l fle

ets

by g

ear t

ype

and

mes

h ba

nd, i

n kW

-day

s un

til 2

005.

Incl

udes

revi

sion

s to

STE

CF–

SGR

ST d

ata

for I

rela

nd a

nd

Bel

gium

in T

able

5.3

.1.

1998

1999

2000

2001

2002

2003

2004

2005

Bea

m tr

awl

Bea

m>=

80B

ELn/

an/

a98

2855

1484

122

1759

801

1541

794

1140

300

1251

345

Bea

m tr

awl

Bea

m>=

80U

K28

3705

2762

1712

7813

2162

1613

8473

2132

3411

0839

1650

15B

eam

traw

lB

eam

(all

mes

hes)

IRL

n/a

n/a

n/a

n/a

n/a

9173

7966

1852

6024

39B

eam

traw

lB

eam

>=80

NED

n/a

n/a

1810

6018

95n/

aD

em T

raw

l >=1

00w

hite

fish

otte

r tra

wls

>=10

0U

K23

9935

1030

0725

1045

4199

7636

6994

4287

0817

7883

1001

17D

em T

raw

l >=1

00tw

in tr

awls

>=1

00U

K12

6534

147

4065

5480

2232

377

098

4009

151

83D

em T

raw

l >=1

00se

ine

nets

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5.3.3 Special Requests 5.3.3.1 EC Request to review 2008 Celtic cod advice ICES has been requested by the European Commission (DG MARE) to review ICES 2007 advice for the exploitation of Celtic Sea cod in 2008:

“ICES is requested to review its own advice for the Celtic Sea cod for 2008, taking account of new information provided in the report of Bellail, Biseau, Horwood and Connoly: “Celtic Sea Cod: Updated forecast using revised recruitment estimates” to the extent this report is considered appropriate by ICES”

Background ICES received the paper by Bellail et al. in April 2008 and has obtained reviews of this paper from three independent scientists. The reviews include a number of critical comments and in general, the reviewers are doubtful whether the RCT3 estimate of the 2006 year class is accurate. However, the use of the RCT3 approach is in accordance with the accepted scientific practice. The review texts are found as Annexes I–III. Bellail et al. estimate the strength of the 2005 (age group 2) and the 2006 (age group 1) year classes based on survey results (the French EVHOE and the Irish IRGFS surveys). These results only became available after the ICES assessment was done. These two surveys both indicate higher year class strengths for the 2005 and 2006 year classes than the values used in the ICES assessment. For the 2006 year class Bellail et al. propose an estimate of 3 318 000 individuals, as opposed to the geometric value of 1 633 000 individuals for the period 2002–2005 which is used in the ICES assessment. ICES Response Review of Bellail et al. (2008) Bellail et al. use the RCT3 method whose estimate is subject to considerable uncertainty and consequently, is not used by ICES for this assessment. The RCT3 method includes an estimate of the general productivity of the stock (recruitment) for the time-series analysed. Bellail et al. use the geometric mean for the period 1970–2006 and shrinks the year class strength estimate towards this mean (3 069 000 ind.). They arrive at an estimate of 3 318 000 ind., indicating that the survey in itself suggests a higher value. ICES considers the productivity of this stock to be below average at present. However, this difference in general perception of the stock productivity does not affect the estimate of the 2006 year class significantly, as demonstrated by Jan Horbowy (see review below in Annex II). The IRGFS data used by Bellail et al. are the preliminary index generated in December 2007, using an historical ALK and including also some non-valid tows; the index has been updated in April 2008. Bellail et al. use survey data for the IRGFS from only Division VIIg. However, data are also available from Division VIIj. The ICES assessment uses a combined index for these two areas. Projection of SSB 2009 relative to Bpa ICES advice in October 2007 (ICES, 2007) - “it is not possible to identify any non-zero catch which is compatible with the precautionary approach” - is based on the SSB reaching Bpa in 2009. A projection was run based on Bellail et al’s estimate of the 2006 year class (3 318 000 ind.) taking into account the fishery in 2007 (Yield of 4 287 t) and supplemented with data from the WGSSDS 2007 report (ICES, 2007a – Table 4.1.13). Bellail et al. suggest that the 2007 is at the 2002–2005 level (1 633 000 ind.) in accordance with the assumption made by ICES in 2007 and this value is used in the projection. The result suggests that an SSB in 2009 of Bpa at 8 800 t can only be achieved if the fishery does not take the full TAC set for 2008. The full range of projections is shown in the figure below. The fishery is subject to high-grading, under-reporting, and area misreporting of landings. It is debated whether recent TACs reflect the removal by the fishery from the stock and hence whether the forecast(s) is valid. The best estimate of the catch of Celtic Sea cod in 2007 is 4 287 t (Colm Lordan, pers. comm.) and the TAC for Division VII set for 2008 is 4 316 t. This includes about 1 200 t taken in Division VIId (North Sea cod) and Division VIIbc (not considered to be part of the Celtic Sea cod) leaving about 3100 t as the minimum expected catch of Celtic Sea cod if the TAC is taken in full (with respect to high-grading and misreporting).


One of the reviewers finds that revising the estimate of the 2005 year class might be considered. The assessment of Celtic Sea cod uses several cpue time-series obtained from the commercial fisheries and the strength of the 2005 year class is therefore estimated based on a wider range of data than just the survey data series. Bellail et al. do not suggest revising the estimate. A revision would require a full update of all the data series with the data for 2007, and ICES will present this update with the advice for 2009. The estimate of the strength of the 2006 year class made by ICES in October 2007 was based on the assumption that the 2002–2005 geometric mean of the estimated recruitment would be appropriate for this year class, i.e. that the expected recruitment would be at the same level as in recent years. The EVHOE (1-group) index for the 2006 year class indicates a strength above the long-term geometric mean recruitment, while the preliminary IRGFS (1-group) survey results indicate a value below the geometric mean, but still above the value used by ICES in October 2007.

Projection Celtic Sea Cod 2008-09

0

3100

6200

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8

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Source of information Bellail, R., Biseau, A., Horwood, J., and Connolly, C. 2008. Celtic Sea cod: Updated forecast using revised recruitment

estimates. (Unpublished report, submitted to ICES through DG MARE, EC). ICES. 2007. Report of the Advisory Committee on Fishery Management, the Advisory Committee on the Marine

Environment, and the Advisory Committee on Ecosystems, 2007. ICES Advice. Book 5. ICES. 2007a. Report of the ICES Working Group on the Assessment of Southern Shelf Demersal Stocks. ICES CM

2007/ACFM:28.


Annex I Coby Needle, FRS Marine Laboratory, Aberdeen Review of Bellail et al.: “Celtic Sea Cod: Updated forecast using revised recruitment estimates” Introduction Bellail et al. (2007) present a revised 2008 catch forecast for Celtic Sea cod. The justification given for this is that the forecast provided by the relevant ICES WG (ICES, 2007) did not include any information on the strength of the incoming year class (the 2006 year class, recruiting in 2007). This short note provides a brief review of Bellail et al. (2007), regarding the quality of the science presented. It also comments on the AGCSC process. It should be read in conjunction with the reviews from my colleagues Jan Horbowy (Poland) and Noel Cadigan (Canada). Review

• The paper does not give much information on the EVHOE and IreGFS surveys. We cannot determine whether they are internally consistent, nor can we see whether they are consistent with other surveys and with the catch data. It is not clear whether the surveys overlap sufficiently with the accepted stock distribution, or what gears are used, or any such details. From the RCT3 outputs (Table 2) we see that the R-sq values for these surveys are quite low – the paper text also highlights this, which does not inspire much confidence about their quality as recruitment indices. I don’t think we can decide whether the new recruitment estimates are better than the old without more information on the new surveys.

• The paper does not include a plot of the time-series of recruitment. This would be important in order to understand why a short time-series average was used by the WG.

• The paper comments that the RCT3 estimate for the 2006 year class is close to the long-term geometric mean. However, that GM includes years in the early 1970s when gadoids in general were very abundant. Is it realistic the use this GM as a mark against which to compare a current estimate?

• The catch-option table in the “Updated forecast” section includes a note saying that the landings have been “corrected for high-grading” – but no information is given about how this is done or what the effect is. I don’t mean a full analysis – just a couple of explanatory lines.

• Is there any anecdotal or quantitative information from the fishery that might support an increased recruitment forecast?

• I found the argument in “Other considerations” extremely weak – basically it says that the RCT3 is a bit unreliable, but the long-term GM is higher than the short-term GM, so let’s use the long-term GM. I don’t find that scientifically defensible.

Comments on the AGCSC process

• The surveys on which the revision is based took place in October-November 2007, and would therefore not have been available to the WG in that year. It would not have been available to the customary October ACFM meeting either, and so has probably never been used before in providing advice. Many stocks have late-year surveys which would be relevant to the advice and quota decisions for the following year, but which cannot be included in that year due to their timing. Is there a precedent for including such information in an in-year advice revision in the way the paper’s authors are attempting?

• While AGCSC has been reviewing the Bellail et al paper, the 2008 meeting of WGSSDS has taken place. It is not yet clear to me whether this has provided a new basis for advice, rendering the Bellail et al paper irrelevant, but this is a possibility. In this context, it is not clear what AGCSC is intended to achieve. We are not in a position to provide advice for the stock, and we have not been asked to review the 2008 WGSSDS recommendations (if there are any), so we have just provided a review of the science in the Bellail et al paper. In general, however, the purpose of groups such as AGCSC needs to be clarified.

References Bellail, R., Biseau, A., Horwood, J. and Connoly, P. 2007. Celtic Sea cod: Updated forecast using revised recruitment

estimates. Unpublished report. ICES. 2007. Report of the ICES Working Group on the Assessment of Southern Shelf Demersal Stocks. ICES CM

2007/ACFM:28.


Annex II Jan Horbowy (Poland) Celtic Sea cod projection – review The key problem seems to be in estimating strength of the 2006 year class. Generally I support using the survey information on year class strength and RCT3 approach to predict recruitment, even if the fit to the data was not very good. The survey weight of the 2006 estimate is 60%, in previous years it was up to 75%. The SE of predicted values are rather large but both survey indicate similar trend of increase recruitment. Both surveys are also used to calibrate XSA (as tuning fleets) but their estimates at age 1 are quite noisy (relatively high SE(logQ) at 0.5-0.7). From retrospective plots of recruitment it seems that the error in estimated R can reach 30-50%. Is there strong biological/environmental reason, that we can expect strength of 2006 y-c as weak as recent 5 y-c (2001-2005) ? If yes, I would assume recent average, if no I would use RCT3 estimate. I think that the use of RCT3 (its parameterization) with available data should be further investigated. In provided WD (Bellail et al) the shrinkage option was used with no time weighting. Thus, the estimate is between signal from survey and VPA-average, which is long-term average covering 1970 onwards. However, recent years recruitment (2001-2005) was week (average of 1633) and used long-term average of over 3000 thousand to which RCT3 estimate shrinks makes the final estimate higher than when used with shrinkage mean of recent 5 years. To investigate that effect one could use RCT3 without shrinkage (generally not recommended) or with shorter VPA series when running RCT3 (e.g. from year class 1995 onwards). I made some calculations and illustrated results in the attached Figure. On the Figure is presented: recruitment from XSA, XSA average recruitment, RCT3 recruitment from WD, RCT3 recruitment calculated be myself assuming no shrinkage (RTC3-NO-shr) and assuming shorter time series (1995 onwards, RCT3-short). For the estimate of y-c 2006, different options seem to have no bigger effect. However, I suggest to look at it further, if the WG intends to apply RCT3 in future.

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Annex III. Noel Cardigan (Canada) Review of ‘Celtic Sea Cod : Updated forecast using revised recruitment estimates’ The forecast update used additional survey data collected since the last WG. This seems a little odd from a process point of view. It could be done every year, and in this event one would have to question the timing of the WG. I am not familiar with the details of RCT3, but I think it is inconsistent for Bellail et. al. to conclude that the RCT3 estimate of the 2005 YC was too uncertain, while the RCT3 estimate of the 2006 YC was accepted. The RCT3 had only 2 survey observations of the 2006 YC, and 4 survey observations for the 2005 YC. I think the 2006 YC estimate is more uncertain than the 2005 estimate. If we believe the XSA then it suggests that the age one indices are quite noisy, and I think it is questionable to put much faith in the 2007 values. I tried to get a sense for this by looking at the SURBA plots in the WG report (pg 229), but I was unsure of what these meant. The reality seems to be that the assessment is uncertain about the strength of recent year classes, and deterministic projections are consequently also uncertain, no matter what values for requirement one uses. This seems to be a matter more of assumption than estimation.. A stochastic projection approach may be more informative.


5.4 Stock summaries

5.4.1 Cod in Division VIIa (Irish Sea)

State of the stock Spawning biomass in relation to precautionary limits

Fishing mortality in relation to precautionary limits

Fishing mortality in relation to highest yield

Fishing mortality in relation to agreed target

Comment

Reduced reproductive capacity

Harvested unsustainably

Overfished Not defined

Based on the most recent estimates of SSB (in 2008), ICES classifies the stock as suffering reduced reproductive capacity. Based on the most recent estimate of fishing mortality (in 2007), ICES classifies the stock as being harvested unsustainably. The stock has been harvested unsustainably since the late 1980s. The fishing mortality in recent years is uncertain, but total mortality remains very high. The spawning-stock biomass has declined ten-fold since the late 1980s and has had reduced reproductive capacity since the mid-1990s. Recruitment has been below average for the past sixteen years, and the six most recent year classes are amongst the smallest on record. Management objectives EU has adopted a recovery plan for this stock (Council Regulation (EC) 423/2004) with the aim to increase the SSB by 30% per year to Bpa. For more details see 5.4.1 Annex. In addition the European Commission has adopted a proposal in April 2008 to amend the EU cod recovery plan (COM(2008) 162 final). ICES has previously concluded that a recovery plan, in order to be precautionary, must include an adaptive element allowing for zero catch through closure of the fisheries for cod until an initial recovery of the cod SSB has been proven. Such an element is not included in the existing plan. ICES therefore considers the EU recovery plan as not consistent with the precautionary approach. Reference points Type Value Technical basis

Blim 6 000 t Blim= Bloss, lowest observed level. Bpa 10 000 t Bpa = MBAL, this level affords a high probability of maintaining the

SSB above Blim. Below this value the probability of below-average recruitment increases.

Flim 1.00 Flim= Fmed Precautionary approach

Fpa 0.72 Fpa: Fmed* 0.72. This F is considered to have a high probability of avoiding Flim. Fishing mortalities above Fpa have been associated with the observed stock decline.

Targets Fy Not defined. (unchanged since: 1998) Yield and spawning biomass per Recruit F-reference points (from 2004 Assessment:) Fish Mort

Ages 2–4 Yield/R SSB/R

Fmax 0.31 2.15 8.00 F0.1 0.18 2.01 12.75 Candidates for reference points consistent with high long-term yields and a low risk of depleting the productive potential of the stock are in the range of F0.1–Fmax.


Single-stock exploitation boundaries Exploitation boundaries in relation to existing management plans Given the highly uncertain estimates of fishing mortality resulting from the assessment, it has not been possible to conduct a short-term forecast on the basis of the management plan. Exploitation boundaries in relation to high long-term yield, low risk of depletion of production potential and considering ecosystem effects Fishing mortalities between F0.1 and Fmax can be considered as candidate target reference points consistent with taking high long-term yields and achieving a low risk of depleting the productive potential. The present fishing mortality is uncertain. However, it is estimated to be well above any candidate reference points. Exploitation boundaries in relation to precautionary limits Given the low stock size and recent poor recruitment, it is not possible to identify any non-zero catch that would be compatible with the precautionary approach. Conclusion on exploitation boundaries Because the existing recovery plan does not include the elements or measures necessary to rebuild the stock at the current SSB (well below Blim), ICES continues to advise on exploitation boundaries in relation to precautionary limits and recommends that the fisheries for cod be closed until an initial recovery of the cod SSB has been proven. Any catches that are taken in 2009 will prolong the recovery to Bpa. Short-term implications Recent mortality values are poorly estimated. However, continuation of total mortality at the recent level is expected to cause further reduction in the spawning-stock biomass in 2009 and 2010 if recruitment varies within the range of the very low values observed since 2002. Management considerations Both the recruitment and reproductive capacity of this stock have become severely impaired in recent years, and the six most recent year classes are amongst the lowest on record. Mortality rates remain very high despite the establishment of a spawning closure since 2000, effort control since 2003, various decommissioning schemes, and a 15–20% TAC reduction per year since 2006. These measures may have prevented a further increase in fishing mortality of cod or may have resulted in some reduction in fishing mortality. However, the current assessment does not provide sufficiently robust estimates of fishing mortality to allow the possible changes to be determined. It will be necessary to reduce all sources of fishing mortality on cod to as close to zero as possible if the stock is to recover above Blim as quickly as possible. STECF (2007a) data show that the main gear types catching cod in the Irish Sea in 2006 were otter trawls with 100 mm+ mesh (44% of cod landings), Nephrops trawls with 70–89 mm mesh (32%), fixed gears (11%), and beam trawls (8%). To minimize the impact of cod recovery measures on fisheries not targeting cod, there will be a need for gear designs and cod avoidance measures that can be proven effective in reducing bycatches of cod to as close to zero as possible. Any measures introduced to reduce cod catches should be accompanied by appropriate monitoring and data collection schemes to determine whether the measures are achieving their stated aims. This includes ensuring accurate data on quantities and composition of fishery removals from all sources. Surveys of cod eggs in the Irish Sea in 2006 indicated that more than half of the spawning took place in areas not included in the spring-spawning closure, indicating that the design of the closure may no longer be optimal. There is evidence of substantial misreporting in the past, but observations at the ports indicate that the implementation of the Registration of Buyers and Sellers legislation since 2006 in the UK and Ireland has improved the accuracy of landings reporting. Management plan evaluations Council Regulation (EC) No. 423/2004, establishing measures for the recovery of cod stocks, was evaluated by ICES in 2006 in relation to Irish Sea cod. The evaluation suggested recovery of SSB to above Bpa by about 2011. This


conclusion was conditional on a large number of assumptions, most importantly the size of recruiting year classes and also an ability to reduce fishing mortality to zero in 2007 to allow the stock to increase above Blim in one year. The operation of the plan depends primarily on annual estimates of SSB in relation to Bpa, but also on estimates of fishing mortality relative to Fpa. The SSB appears to be estimated well by the assessment. However, estimates of fishing mortality are highly uncertain because they cannot be partitioned between landings and discards and other sources. Hence, it is not possible to reliably determine TACs that meet the conditions of the management plan, including maintaining fishing mortality below Fpa. Impacts of fisheries on the ecosystems Although a number of gear selectivity devices such as square mesh panels are mandatory, their effectiveness is variable in mixed fisheries and catches can contain a range of non-commercial or low value species together with undersized individuals of commercial species, depending on size selectivity. Rates of discarding can be considerable at times in small-mesh demersal fisheries. The large fishing effort of Nephrops vessels in the Irish Sea can result in a substantial quantity of discards by the fleet over the year even if the quantities discarded from individual hauls may appear relatively small. Fishing patterns and gear designs that reduce or eliminate discarding will contribute to reduce the impacts of fishing on the ecosystem. Beam trawling, especially using chain-mat gear, is known to have a significant impact on the benthic communities, although less so on soft substrates and in areas which historically have been exploited by this fishing method. Factors affecting the fisheries and the stock Regulations and their effects The fishery is managed by a combination of TAC, area closures, technical measures, and effort restrictions. These do not seem to have been effective in controlling catches or sufficient to rebuild the stock to precautionary levels. The regulations are described in more detail in the area overview. The regulations have had the following effects on Irish Sea cod and fisheries taking cod:

In 2000, the cod spawning grounds were closed for ten weeks from mid-February to maximize the reproductive output of the stock (EU Regulations 304/2000 and 2549/2000). Revisions in 2001, 2002, and 2003 reduced the closure to the western Irish Sea only, coupled with changes in net design to improve selectivity. There are various derogations for gears not targeting cod, notably Nephrops trawls. During the closure, whitefish trawlers have been displaced to other fishing grounds or have switched to Nephrops trawling using 70–89 mm mesh nets. On the basis of the information available, STECF (2007b) was unable to determine the extent to which the closure has reduced fishing mortality to a lower value than would otherwise have occurred, through protection of adult cod during spawning or through influencing changes in fishing effort in the different fleets. STECF advised that a comprehensive evaluation of how fleet activities have been affected by the closure and other regulations and factors is required to evaluate the cod closure.

The cod recovery plan introduced a system for limiting fishing effort by adjusting the number of fishing days

allowed for various vessel categories deploying gears with various mesh sizes. STECF (2007a) reported that the fishing effort of trawlers using 100–119 mm mesh and with more than 5% cod in their landings declined by 63% between 2003 and 2006. This is due to a combination of factors restricting the activities of these vessels. A number of whitefish vessels switched to Nephrops gears to take advantage of the additional days at sea and the high value of Nephrops, and some were removed from the fleet. Despite vessels switching from whitefish to Nephrops fishing, the fishing effort of trawlers with 70–89 mm mesh declined by 7% between 2003 and 2006, partly due to vessel decommissioning and increased fishing in the North Sea.

Changes in fishing technology and fishing patterns Effort regulation, and closures of cod spawning grounds in the Irish Sea and the Firth of Clyde, encouraged a number of vessel operators to reduce mesh size and shift to other fisheries, particularly to Nephrops fishing. This has implications for catch compositions and the selectivity of the fishery. Some vessels now fish seasonally in the North Sea. Increasing fuel prices have also been a factor in altering the fishing patterns in some fleets.


Impacts of the environment on the fish stock There is evidence that the reduction in cod recruitment observed in the Irish Sea since the 1990s may be due to a combination of small spawning-stock biomass and poor environmental conditions, coinciding with a shift towards above-average sea temperatures (ICES, 2006). Scientific basis Data and methods The quality of the commercial landings and catch-at-age data for this stock deteriorated in the 1990s following reductions in the TAC without associated control of fishing effort. ICES has attempted to improve the accuracy of the landings data by replacing the reported landings figures in 1991–1999 from three major Irish Sea ports by estimates derived from a sampling scheme. The sampling scheme had insufficient coverage in some subsequent years, and the assessment model (B-Adapt) implements a procedure for estimating any unaccounted removals of cod since 2000. All removals prior to 2000 are assumed to be accounted for, apart from discards which are not included in the assessment. The procedure estimates the quantity of total removals since 2000 needed for catch-based estimates of abundance to follow the same trends over time given by several series of survey indices. Any unaccounted removals are assumed to have the same age composition as the reported landings. The model estimates of unaccounted removals since 2000 are up to three times larger than reported landings for those years. The existence of substantial unaccounted removals can explain the lack of any improvement in age structure of cod and the continuation of an apparently high mortality rate well in excess of the precautionary approach reference points. The ability to implement a management plan for this stock will remain compromised until all sources of significant unaccounted mortality are identified. Recent discard estimates available for some fleets indicate a variable, but high discard rate for 1-year-olds. Some 0-group cod are also caught, and all are discarded. Estimates of discarding are not used in the assessment due to the short time-series and variable quality of the data. Information from the fishing industry The UK Fisheries–Science Partnership surveys of the Irish Sea cod spawning grounds in spring 2005–2008, carried out using commercial trawlers, indicated a widespread distribution of cod mostly at low density but with some localized aggregations. The time-series of SSB indices shows a downward trend similar to that shown by the other surveys used in the assessment, and the highly truncated age composition of cod in the surveys supports the ICES assessment, indicating continuing high mortality rates. A UK/Republic of Ireland self-sampling programme started in 2007 and is currently ongoing. This is a voluntary scheme involving vessels from the United Kingdom and Republic of Ireland. Haul-by-haul catch and discard information is collected and samples of discards bought ashore for scientists to analyse. The scheme is still in its early stages and the time-series was insufficient to be used in this assessment. Uncertainties in assessment and forecast The assessment indicates additional, unaccounted removals from the stock in recent years, which are not explained from the recent observation of reported landings. Sampling levels for length and age composition of landings deteriorated in 2003 due to port samplers being denied access to landings at several major ports. Some limited access was permitted in 2004 at these ports, but access improved in 2005 and coverage in 2007 was good. A large but variable proportion of the catch of one-year-old cod is discarded. Discards are not included in the assessment, leading to a large underestimate of the mortality at this age. Trends in spawning-stock biomass and recruitment appear to be well estimated in this stock. Comparison with previous assessment and advice The perception of the stock status is similar to last year and the basis for the advice is the same.


Sources of information ICES. 2006. Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 9–18 May 2006 (ICES CM 2006/ACFM:30). ICES. 2008. Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 15–21 May 2008 (ICES CM 2008/ACOM:08). STECF. 2007a. Report on fishing effort regime (SGRST-07-02 and 07-04). STECF. 2007b. Evaluation of closed area schemes (SGMOS-07-03).

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se in

F; i

nter

actio

n w

ith N

ephr

ops

10

.3

15

.0

13.2

12

.9

1988

N

o in

crea

se in

F; i

nter

actio

n w

ith N

ephr

ops

10

.1

15

.0

15.8

14

.2

1989

N

o in

crea

se in

F

13

.4

15

.0

11.3

1 12

.8

1990

F

at F

med

; TA

C

15

.3

15

.3

9.91

7.4

1991

St

op S

SB d

eclin

e; T

AC

6.

0

10.0

7.

01 7.

12 19

92

20%

of F

(90)

~ 1

0 00

0 t

10

.0

10

.0

7.4

7.72

1993

F m

ed ~

10

200

t

10.2

11.0

5.

9 7.

62 19

94

60%

redu

ctio

n in

F

3.

7

6.2

4.5

5.42

1995

50

% re

duct

ion

in F

3.9

5.

8 4.

5 4.

62 19

96

30%

redu

ctio

n in

F

5.

4

6.2

5.30

4.

962

1997

30

% re

duct

ion

in F

5.9

6.

2 4.

44

5.86

2 19

98

No

incr

ease

in F

6.2

7.

1 4.

96

5.31

2 19

99

Redu

ce F

bel

ow F

pa

4.

9

5.5

2.96

4.

782

2000

Lo

wes

t pos

sible

F

0

2.

1 1.

42

1.27

3

2001

Lo

wes

t pos

sible

F

0

2.

1 2.

03

2.25

3

2002

Es

tabl

ish re

cove

ry p

lan

-

3.

2 2.

7 2.

693

2003

Cl

osur

e of

all

fishe

ries f

or c

od

-

1.

95

1.5

1.28

3 20

04

Ze

ro c

atch

0 2.

15

1.1

1.07

3 20

05

Ze

ro c

atch

0 2.

15

0.97

0.

913

2006

Zero

cat

ch

0

1.82

8 0.

94

0.84

3 20

07

Ze

ro c

atch

0 1.

462

1.09

0.

703

2008

Zero

cat

ch

0

1.19

9

20

09

Ze

ro c

atch



Figure 5.4.1.1 Cod in Division VIIa: landings and stock trends from final B-Adapt runs. Continuous line on

landings plot is the reported landings; filled squares are landings in 1991–2002 and 2005 incorporating sample-based estimates at three ports; open circles with 90% confidence intervals are total catches estimates (in excess of assumed natural mortality) from B-Adapt. Dotted lines on plots are 5th and 95th bootstrap percentiles.

SSB

0

5000

10000

15000

20000

25000

1968

1970

1972

1974

1976

1978

1980

1982

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

2008

SSB

( t)

Bpa

Blim

Recruitment

0

5000

10000

15000

20000

1968

1970

1972

1974

1976

1978

1980

1982

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

Nos

at a

ge 0

('00

0)

Fishing mortality (age 2-4)

0.0

0.5

1.0

1.5

2.0

2.5

1968

1970

1972

1974

1976

1978

1980

1982

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

F

Fpa

Landings

0

2000

4000

6000

8000

10000

12000

14000

16000

1968

1970

1972

1974

1976

1978

1980

1982

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

2008

Land

ings

(t)

Flim

Landings / Catches

Land

ings

/ C

atch

es (t

)

ICES

Adv

ice

2008

, Boo

k 5

48Tab

le 5

.4.1

.1

Nom

inal

land

ings

(t) o

f CO

D in

Div

isio

n V

IIa

as o

ffic

ially

repo

rted

to IC

ES, a

nd fi

gure

s use

d by

ICES

.

Coun

try

1994

19

95

1996

19

97

1998

19

99

2000

20

01

2002

20

03

2004

20

05

2006

20

071

Belg

ium

12

9 18

7 14

2 18

3 31

6 15

0 60

28

3 31

8 18

3 10

4 11

5 60

67

Fran

ce

208

166

148

268

269

n/a

53

74

116

151

29

35

182

14

Irela

nd

1,50

6 1,

414

2,47

6 1,

492

1,73

9 96

6 45

5 75

1 1,

111

594

380

220

2752

585

Net

herla

nds

- -

25

29

20

5 1

- -

-

Spai

n -

- -

- -

- -

- -

14

- -

UK

(Eng

land

, Wal

es &

NI)

2,27

4 2,

330

2,35

9 2,

370

2,51

7 1,

665

799

885

1,13

4 50

5 64

6 59

4 59

12 42

5

UK

(Isle

of M

an)

26

22

27

19

34

9 11

1

7 7

5

UK

(Sco

tland

) 32

6 41

4 12

6 80

67

80

38

32

29

23

15

3

62

Tota

l 4,

469

4,53

3 5,

303

4,44

1 4,

962

2,87

5 1,

417

2,02

6 2,

715

1,47

7 1,

179

967

950

1,09

1

Una

lloca

ted

933

54

-339

1,

418

356

1,90

9 -1

43

226

-20

-192

-1

07

-57

-110

-3

89

Tota

l as u

sed

by IC

ES

5402

3 45

873

4964

3 58

593

5318

3 47

843

1274

4 22

524

2695

4 12

854

1072

4 91

04 84

04 70

24

1 Prel

imin

ary.

2 Revi

sed.

3 incl

udes

sam

ple-

base

d es

timat

es o

f lan

ding

s int

o th

ree

ports

4 b

ased

on

offic

ial d

ata

only

. n/

a =

not a

vaila

ble.



5.4.1 Annex

The European Commission has enacted a Council Regulation ((EC) No. 423/2004) which establishes measures for the recovery of cod stocks: For stocks above Blim, the harvest control rule (HCR) requires:

1. setting a TAC that achieves a 30% increase in the SSB from one year to the next, 2. limiting annual changes in TAC to ± 15% (except in the first year of application), and, 3. a rate of fishing mortality that does not exceed Fpa.

For stocks below Blim the Regulation specifies that:

4. conditions 1-3 will apply when they are expected to result in an increase in SSB above Blim in the year of application,

5. a TAC will be set lower than that calculated under conditions 1-3 when the application of conditions 1-3 is not expected to result in an increase in SSB above Blim in the year of application.


5.4.2 Cod in Divisions VIIe–k (Celtic Sea Cod)





Comment

Increased risk Harvested sustainably

Overfished NA

SSB has been below Blim since 2004 and the most recent estimate of SSB is slightly above Blim. Fishing mortality has been very high since the mid-1980s, but has declined since 2002 and is now below Fpa. Recruitment since 2002 has been well below average. Management objectives There are no specific management objectives or a management plan for this stock. The European Commission has adopted a proposal in April 2008 to amend the EU cod recovery plan (COM(2008) 162 final). The EC proposal includes Celtic Sea cod. Reference points Type Value Technical basis

Blim 6 300 t Blim = Bloss.(B76), the lowest observed spawning-stock biomass. Bpa 8 800 t Bpa = Blim * 1.4. Biomass above this value affords a high probability

of maintaining SSB above Blim, taking into account the variability in the stock dynamics and the uncertainty in assessments.

Flim 0.90 The fishing mortality estimated to lead to potential collapse. Precautionary approach

Fpa 0.68 Fpa = 5th percentile of Floss. This F is considered to have a high probability of avoiding Flim and maintaining SSB above Bpa in the medium term (assuming normal recruitment), taking into account the uncertainty assessments.

Targets Fy Not defined. (unchanged since: 2004) Yield and spawning biomass per Recruit F-reference points:

Fish Mort Yield/R SSB/R Ages 2–5 Average last 3 years 0.67 2.02 3.11 Fmax 0.37 2.21 7.47 F0.1 0.23 2.09 12.24 Fmed 0.71 1.98 2.82

Fishing mortalities in the range of F0.1 = 0.23 to Fmax = 0.37 can be considered as candidate target reference points which are consistent with taking high long-term yields and achieving a low risk of depleting the productive potential. Single-stock exploitation boundaries Exploitation boundaries in relation to high long-term yield, low risk of depletion of production potential and considering ecosystem effects The current fishing mortality is estimated at 0.67, which is well above the range that would lead to high long-term yields and low risk of stock depletion.


Exploitation boundaries in relation to precautionary limits The exploitation boundaries in relation to precautionary limits imply landings of less than 2600 t in 2009, which is expected to rebuild SSB to the Bpa (= 8800 t) in 2010. Conclusion on exploitation boundaries ICES recommends a 50% reduction in fishing mortality which is associated with landings in 2009 of 2600 t; the SSB is then expected to reach Bpa in 2010. This fishing mortality also corresponds to high long-term yield and low risk of stock depletion. Short-term implications Outlook for 2009 Basis: F (2008) = mean F(2005–07) = 0.67; R = GM(2002–06) = 1.784; SSB (2009) = 7.066; landings (2008) = 4.8. Rationale Landings

(2009) Rel. effort (2009 compared to 2008) 1)

Basis F (2009) SSB (2010) %SSB change 2)

Zero catch 0 0.00 F=0 0.00 12.3 74% 4.5 1.01 Fpa = Fsq*1.01 0.68 6.4 -9% Precautionary limits

2.6 0.51 Bpa 0.34 8.8 25% High long-term yield 2.8 0.55 F (long-term yield) 0.37 8.6 22%

0.6 0.10 Fsq * 0.1 0.07 11.5 63% 1.4 0.25 Fsq * 0.25 0.17 10.5 49% 2.6 0.51 Fsq * 0.5 0.34 8.9 26% 3.6 0.75 Fsq * 0.75 0.50 7.6 8% 4.2 0.90 Fsq * 0.90 0.60 6.9 -2% 4.5 1.00 Fsq 0.67 6.5 -8% 4.8 1.10 Fsq * 1.1 0.74 6.1 -14%

Status quo

5.2 1.25 Fsq * 1.25 0.84 5.5 -22% Units: ‘000 tonnes. Shaded scenarios are not considered consistent with the precautionary approach. 1) Under the assumption that effort is linearly related to fishing mortality. 2) SSB 2010 relative to SSB 2009. Management considerations The advice in 2007 was for a zero catch of cod because the forecast indicated that only a zero catch in 2008 would allow SSB to almost achieve Bpa in 2009. The advice this year is for a 50% reduction in fishing mortality, which is expected to allow rebuilding of the stock to Bpa in 2010. The results of this assessment are broadly consistent with those of last year in terms of trends in fishing mortality, SSB, and recruitment. The main change in the perception is the upward revision of the 2005 year class by 74% and an upward revision of SSB in 2007 by 14%. In addition, the 2006 year class which was assumed to be average in the forecast last year, is now estimated 67% higher. This is included in the forecast catch for 2009 and the forecast SSB for 2010. The assessment area covers Divisions VIIe–k and the ICES advice applies to these areas only; however, the TAC is set for Divisions VIIb–k, Subareas VIII, IX, X, and CECAF 34.1.1. Within this larger area there is no control over where the catches are taken. Current management measures for Divisions VIIe–k include cod in Divisions VIIbc and cod in Division VIId. Cod in Division VIId is assessed together with cod in the North Sea. Whatever management measures are implemented, they must be consistent with the assessment area. Cod in Divisions VIIe–k is caught in a range of fisheries including gadoid trawlers, Nephrops trawlers, otter trawlers, beam trawlers, and gillnetters. Other commercial species that are caught by these fisheries include haddock, whiting, Nephrops, plaice, sole, anglerfish, hake, megrim, and elasmobranchs. In the recent past there were indications of underreporting of cod landings in some fleets. The introduction of the buyers and sellers legislation in UK and Ireland may have reduced this, but may also have increased discards. Measures aimed at reducing discarding and improving the fishing pattern should be encouraged. These might include spatial and


temporal changes in fishing practices or technical measures. These measures would need to be evaluated in the context of other species caught in mixed fisheries. This stock has had a truncated age structure observed in the landings over many years. The historical dynamics of Celtic Sea cod have been “recruitment driven”, i.e. the stock increased in the past in response to good recruitments and decreased rapidly during times of poor recruitment. Recruitment in recent years appears to be poor. Fishing mortality should be reduced in the longer term to maximize the contributions of recruitment to future SSB and yield and will result in reduced risk to the stock. The displacement of effort from areas with existing effort control regimes (Division VIIa, Subareas VI and IV) would have a detrimental effect on measures to reduce mortality on cod in the Celtic Sea. Ecosystem considerations Cod in the Celtic Sea are at the southern limit of the range of the species in the Northeast Atlantic. It is known that at the southern limits of their range, recruitment tends to decrease in warmer waters (above 8.5°C) and that cod are not found in waters warmer than 12°C. Celtic Sea cod has higher growth rates and mature earlier than other cod stocks. Previous tagging studies have given no evidence of cod movement out of Division VIIe and into VIIfg, where there appears to be a simple inshore-offshore migration between deep-water wrecks and reefs in the summer and inshore spawning areas in the winter. Past tagging work in the Irish Sea suggested that only a small component of cod landings from the Celtic Sea are fish which spawn in the Irish Sea. Factors affecting the fisheries and the stock Cod in Divisions VIIe–k are taken in mixed trawl fisheries. Landings are made mainly by French gadoid trawlers, which prior to 1980 were mainly fishing for hake in the Celtic Sea. Landings of cod by French Nephrops trawlers have fluctuated between 10% and 20% of the total French cod landings from this stock in recent years. Since 1988, Irish landings have accounted for on average 14% of the total, but have in the past three years accounted for around 28%. UK and Belgium have contributed on average 9% and 4% of the total landings, respectively. Landings occur throughout the year, but mainly in winter from November to April, with a peak in February–March. Since 1999, French fishing effort has decreased considerably: by 50% for all trawlers and by 65% for the gadoids fleets during the first quarter. This reduction is mostly due to a decrease in the number of vessels involved rather than to a reduction of the mean fishing time per vessel. The effects of regulations In 2005 and 2006, part of the Celtic Sea was temporally closed (Trevose closure) during the 1st quarter. The impact of this closure was evaluated by ICES last year in response to a special request from the EC and it could not be quantitatively disentangled from other factors. The displacement of fishing activities away from spawning aggregations is expected to reduce fishing mortality on mature cod during the spawning season. The closure has led to a reduction in the effort of French vessels targeting gadoids. Technical measures applied to this stock are: a minimum mesh size for beam and otter trawlers in Subarea VII and a minimum landing size (MLS) of 35 cm. For Belgian trawlers that land in Belgium the MLS is 40 cm. Minimum landing sizes do not prevent cod from being discarded, but might prevent the targeting of juvenile cod. Recent sampling programmes in countries exploiting this stock indicate that discarding is high and variable. They may account for 40–60% by number of all fish caught. These discards were mainly under the MLS until recently when high grading became more prominent in the fishery. The most pertinent changes to fishing pattern for cod has been the increased high-grading and discarding in response to restrictive quotas since 2002. High-grading has occurred in French fisheries since 2003 and was also apparent in UK fisheries in 2007. Due to quota restrictions all catches were discarded in the French fishery in quarter 4 in 2002, and in the Irish fishery in quarters 3 and 4 in 2007. This is expected to be a problem again in 2008 because around 80%+ of the Irish quota in the Celtic Sea area was caught by mid-March. Scientific basis Data and methods The assessment is based on landings, three surveys, and four commercial cpue series. Discard data are not included in the assessment, although there was a correction of high-grading for 2003 to 2005 in the French fisheries.


Information from the fishing industry The industry has been cooperative in a number of scientific endeavours with regards to improving the information base for this stock. The French industry has been involved in a self-sampling project in 2008. The UK fisheries science partnership, conducted cooperatively between CEFAS and the UK industry has provided information on the relative age compositions, suggesting that the main year-class signals are captured by the assessment. The Irish industry has participated in two Fisheries Science Partnership projects tagging cod and scoping out a new survey design for this stock. The fisheries representatives from France, UK, and Ireland, all reported that cod was abundant and widespread in the Celtic Sea in the springs of 2007 and 2008. They also further highlighted the issue of restrictive quotas resulting in high-grading. The industry questioned the accuracy of recent recruitment estimates in the 2007 WG assessment. The restrictive nature of the TAC has resulted in certain fleets avoiding areas where small cod are known to occur. Uncertainties in assessment and forecast The main uncertainties in this assessment are partial information available on recent quota-induced changes in discarding, underreporting, and area misreporting of landings. The uncertainties in the forecasts are associated with the strength of the incoming and assumed recent recruitment estimates and any future high-grading practice. Comparison with previous assessment and advice The results of this assessment are consistent with those of last year in terms of trends in fishing mortality, SSB, and recruitment. This year the main change is the upward revision of the 2005 year class by 74% and an upward revision of SSB in 2007 by 14%. The advice in 2007 was for a zero catch of cod because the forecast indicated that only a zero catch in 2008 would allow SSB to almost achieve Bpa in 2009. The advice this year is for a 50% reduction in fishing mortality, which is expected to allow rebuilding of the stock to Bpa in 2010. ICES has issued separate advice on a request by the European Commission (DG MARE) to review ICES 2007 advice of Celtic Sea cod in 2008 (see Section 5.3.3.1). The conclusion of that advice was that revising the estimate of the 2005 year class could be considered and that such a revision would require a full update of all the data series. The update (see above) has revised the estimate of the 2005 year class upwards by 74% and this is included in the forecast catch for 2009 and the forecast SSB for 2010. Source of information Report of the Working Group on the Assessment of Southern Shelf Demersal Stocks, 30 April–6 May 2008 (ICES CM 2008/ACOM:12).


Year ICES

Advice Predicted catch

corresp. to advice Agreed TAC1

ICES Landings

ICES Landings +

High-grading estimates

1987 Reduce F < 6.42 10.2 1988 No increase in F; TAC 7.02 17.2 1989 No increase in F; TAC 8.62 19.8 1990 No increase in F; TAC 9.22 12.7 1991 TAC; SSB = mean 4.52 9.3 1992 Appropriate to reduce F - 9.7 1993 20% reduction in F 6.52 19.0 10.4 1994 20% reduction in F 5.62 17.0 10.6 1995 20% reduction in F 4.73 17.0 11.7 1996 20% reduction in F 4.73 20.0 12.6 1997 20% reduction in F 7.44 20.0 12.0 1998 10% reduction in F 8.84 20.0 11.4 1999 Reduce F below Fpa 9.24 19.0 8.6 2000 Reduce F below Fpa < 7.65 16.0 6.5 2001 40% reduction in F < 4.35 10.5 8.3 2002 45% reduction in F < 5.35 8.7 9.4 2003 60% reduction in F < 3.85 6.7 6.2 6.4 2004 90% reduction in F or

management plan <0.7 5.7 3.5 3.6

2005 17% reduction in F <5.2 6.2 3.1 3.1 2006 No increase in effort [should

have been reduce effort] Cannot be estimated

5.6 3.4 3.4

2007 Zero catch 0 4.7 4.3 Na 2008 Zero catch 0 4.3 2009 50% reduction in F <2.6

Weights in ‘000 t. 1TAC covers Subareas VII (except Division VIIa) and VIII. 2 For the VIIf+g stock component. 3 For the VIIf–h stock component. 4 For the VIIe–h stock component. 5 For the VIIe–k stock component.


Figure 5.4.2.1 Cod in Divisions VIIe–k. Landings, fishing mortality, recruitment, and SSB.

Landings

0

5

10

15

20

25

1971 1976 1981 1986 1991 1996 2001 2006

Land

ings

in 1

000

t

Fishing Mortality

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1971 1976 1981 1986 1991 1996 2001 2006

F(ag

es 2

-5) F

Flim

Fpa

Recruitment (age 1)

02468

1012141618

1971 1976 1981 1986 1991 1996 2001 2006

Rec

ruitm

ent i

n m

illio

ns

Spawning Stock Biomass

0

5

10

15

20

25

30

1971 1976 1981 1986 1991 1996 2001 2006

SSB

in 1

000

t

SSB

Blim

Bpa


Figure 5.4.2.2 Cod in Divisions VIIe–k. Stock and recruitment; yield, and SSB per recruit.

Stock - Recruitment

02468

1012141618

0 5 10 15 20 25 30

SSB in 1000 t

Rec

ruitm

ent (

age

1) in

m

illio

ns SSB-Rec.

Blim

Bpa

Yield and Spawning Stock Biomass per Recruit

0

0.5

1

1.5

2

2.5

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6

Fishing Mortality (ages 2-5)

Yiel

d (d

ashe

d lin

e)

0510

15202530

3540

SSB

(lin

e)

Precautionary Approach PlotPeriod 1971-2007

0

5

10

15

20

25

30

0.0 0.2 0.4 0.6 0.8 1.0 1.2


SSB

in 1

000

t

F-SSB

2007

Flim

Fpa

Blim

Bpa


Cod in Divisions VIIe-k

0

5

10

15

20

25

30

1990 1995 2000 2005

SSB ('000 tonnes)

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1990 1995 2000 2005

Fishing mortality: 2-5

0

2

4

6

8

10

12

14

16

18

1990 1995 2000 2005

Recruitment. Age: 1 (millions)

Figure 5.4.2.3 Cod in Divisions VIIe–k. Historical performance of the assessments.


Year Recruitment SSB Landings Mean F Age 1 Ages 2–5 thousands tonnes tonnes

1971 3075 8939 5782 0.628 1972 565 8221 4737 0.582 1973 1665 7673 4015 0.610 1974 500 7410 2898 0.419 1975 3888 6622 3993 0.755 1976 1202 6301 4818 0.632 1977 1713 7681 3059 0.400 1978 1689 8614 3647 0.405 1979 4241 8946 4650 0.508 1980 7912 9452 7243 0.735 1981 3355 10341 10597 0.834 1982 1340 13012 8766 0.624 1983 4617 13427 9641 0.779 1984 4324 10339 6631 0.510 1985 3898 13449 8317 0.532 1986 3224 13413 10475 0.817 1987 16553 10786 10228 0.871 1988 8186 14690 17191 0.671 1989 2487 24062 19809 0.840 1990 2642 17947 12749 0.940 1991 7458 9960 9336 1.066 1992 7702 8106 9747 0.923 1993 2279 10965 10425 0.832 1994 8957 12968 10620 0.811 1995 6247 11685 11709 0.794 1996 4784 14368 12681 0.909 1997 6575 12809 12035 0.896 1998 3278 11191 11431 1.056 1999 1613 9684 8594 1.011 2000 7217 6511 6536 0.909 2001 5988 7104 8308 0.930 2002 1536 9456 9356 0.967 2003 914 8233 6420 0.946 2004 2057 4768 3672 0.848 2005 2622 3857 3128 0.810 2006 2385 4365 3369 0.600 2007 2729 5879 4287 0.602 2008 1784* 6794

Average 4032 10001 8132 0.757 * GM2002–2006.

Table 5.4.2.1 Cod in Divisions VIIe–k.


Table 5.4.2.2 Cod in Divisions VIIe–k. Nominal landings of cod in Divisions VIIe–k used by the Working Group.

Year Belgium France Ireland UK Others Total 1971 5782 1972 4737 1973 4015 1974 2898 1975 3993 1976 4818 1977 3058 1978 3647 1979 4650 1980 7243 1981 10596 1982 8766 1983 9641 1984 6631 1985 8317 1986 10475 1987 10228 1988 554 13863 1480 1292 2 17191 1989 910 15801 1860 1223 15 19809 1990 621 9383 1241 1346 158 12749 1991 303 6260 1659 1094 20 9336 1992 195 7120 1212 1207 13 9747 1993 391 8317 766 945 6 10425 1994 398 7692 1616 906 8 10620 1995 400 8321 1946 1034 8 11709 1996 552 8981 1982 1166 0 12680 1997 694 8662 1513 1166 0 12035 1998 528 8096 1718 1089 0 11431 1999 326 5488 1883 897 0 8594 2000 208 4281 1302 744 0 6535 2001 347 6033 1091 838 0 8309 2002 555 7489 694 618 0 9356 Highgrading FR Total 2003 136 5222 517 346 0 6221 199 6420 2004 153 2425 663 282 0 3523 149 3672 2005 186 1686 870 309 0 3051 77 3128 2006 103 1939 959 368 0 3369 not estimated 3369

2007* 108 2572 1197 410 0 4287 not estimated 4287 * provisional Scaled landings 1971–1987 (SSDS WG 1999)


Table 5.4.2.3 Nominal landings (t) of cod in Division VIIb,c for 1995–2007. COUNTRY 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 France 91 115 71 44 …1 46 38 54 33 13 16 10 14 Germany - - 3 - - - - - Ireland 282 353 177 234 154 141 107 59 59 60 32 16 11 Netherlands - - - - - - + - 1 Norway 3 1 6 11 +* 1 5 1 1 Spain 6 3 6 2 3 1 1 UK(E/W/NI) 25 35 37 25 4 4 2 1 8 UK(Scotland) 66 12 7 9 1 - 1 1 10 UK 2 1 TOTAL 473 519 301 318 172 194 150 122 102 83 48 29 27


5.4.3 Haddock in Division VIIa (Irish Sea)





Comment

Undefined Undefined Undefined Undefined The state of the stock is uncertain. Stock trends indicate an increase in SSB over the time-series. Recent recruitments appear to be above average and have contributed to a rise in the SSB. Total mortality remains stable. Management objectives There are no explicit management objectives for this stock. Reference points Type Value Technical basis

Blim Not defined. Bpa Not defined. Flim Not defined.

There is currently no biological basis for defining appropriate reference points, in view of the rapid expansion of the stock size over a short period and the inability to conduct a full analytical assessment.

Precautionary approach

Fpa 0.5 ICES proposed that Fpa be set at 0.5 by association with other haddock stocks.

Targets Fy Not defined. (unchanged since: 1998) Single-stock exploitation boundaries Exploitation boundaries in relation to precautionary limits The available information is inadequate to evaluate spawning-stock or fishing mortality relative to precautionary reference points. SSB is increasing and recent recruitments appear to be above average. ICES recommends that fishing effort should not be allowed to increase. Short-term implications Given that the current assessment is indicative of trends only and fishing mortality is unknown, it has not been possible to conduct a short-term forecast of catches. Management considerations The EU Cod Recovery Plan implemented in the Irish Sea from 2004 will affect catches of species caught in related fisheries, including haddock. The current directed fishery for haddock in the Irish Sea is likely to generate bycatches of cod in the same area. However, in recent years there has been a temporal shift of the haddock fishery to predominantly the second half of the year. A reduced bycatch of cod is expected since there is, at this time, less overlap between haddock and adult cod distributions, compared to spring. Limited sampling schemes since the 1990s have shown high rates of discarding of haddock less than 3 years old, and variable discarding of 3-year-olds in fisheries using 70–80 mm mesh nets. Samples from whitefish vessels since the introduction of 100+ mm mesh and other recent technical measures are too few to form a basis for evaluation of discards in that fleet. However, any measures to reduce discards will result in increased future yield. The TAC has been restrictive in 2007 and became exhausted in the third quarter for some member states. ICES advises no increase in effort. Under the assumption of constant effort, the recent increase in abundance would create increased catch opportunities.


Factors affecting the fisheries and the stock Regulations and their effects Due to the bycatch of cod in the haddock fishery, the regulations affecting Division VIIa haddock remain linked to those implemented under the Irish Sea cod recovery plan. The regulations implemented for cod are detailed in the overview for the Irish Sea. The extent to which fishing mortality may have been reduced in recent years by management measures such as effort limitation and decommissioning of vessels could not be reliably evaluated. Changes in fishing technology and fishing patterns The introduction of effort regulation has effectively encouraged vessel operators to reduce mesh size and shift to other fisheries, particularly to Nephrops trawling, in order to gain more days at sea. This has implications for catch compositions and the selectivity of the fishery. Impacts of the environment on the fish stock Declining trends in length and weight-at-age in the stock over time are apparent. Environmental factors may have contributed to the reduced growth, but the relationship is unclear. Scientific basis Data and methods An assessment was carried out based on survey information only and is considered to be indicative of trends only. Information from the fishing industry The UK Fishery Science Partnership Irish Sea roundfish survey, 2004–2007 that was carried out using commercial trawlers, indicated similar year-class signals to research vessel surveys. This survey supports the conclusions of the assessment. Uncertainties in assessment and forecast Landings data have not been used in the assessment. Landings data for this stock are uncertain because of species misreporting, which has been estimated from quayside observations in one country only. Restrictive quotas for some countries caused extensive misreporting during the 1990s prior to the introduction of a separate TAC allocation for the Irish Sea. Estimates of misreporting have been included in the estimates of landings, except for 2003. The recent implementation of Buyers and Sellers legislation has potentially improved the quality of the landings data in 2006 and 2007. Discard sampling levels have increased in recent years. The highly variable and very large estimates of discarding for this fishery that have been observed previously are still evident. Sampling levels for length and age composition of landings deteriorated in 2003 due to port samplers being denied access to landings at several major ports. There was some limited access permitted in 2004 at these ports, but access improved in 2005 and coverage in 2007 was good. Comparison with previous assessment and advice The perception of the stock, the assessment, and the advice are the same as last year. Source of information Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 15–21 May 2008 (ICES CM 2008/ACOM:08).


Year ICES

Advice Single-stock exploitation boundaries

Predicted catch corresp. to advice

Predicted catch

corresponding to single-

stock boundaries

Agreed TAC1

Official Landings

ICES Landings

1987 Not dealt with 1.287 1.287 1988 Not dealt with 0.747 0.7`47 1989 Not dealt with 0.560 0.560 1990 Not dealt with 0.582 0.582 1991 Not dealt with 0.616 0.616 1992 Not dealt with 0.703 0.656 1993 Not dealt with 0.730 0.813 1994 Not dealt with 0.681 1.043 1995 Not dealt with 61 0.841 1.753 1996 No advice 71 1.453 3.023 1997 Means of setting

catch limits req’d 141 1.925 3.391

1998 Catch limit for VIIa 3.0 201 3.015 4.902 1999 No increase in F;

Catch limit for VIIa 7.0 4.992 2.370 4.129

2000 Reduce F below Fpa <2.8 3.42 2.447 1.380


2002 Reduce F below Fpa <1.20 1.32 1.115 1.972 2003 No cod catches - 0.62 0.674 n/a 2004 F<Fpa <1.5 1.52 0.761 1.278 2005 F<Fpa <1.37 1.37 0.547 0.699 2006 Substantial

reduction in fishing mortality

- 1.275 0.655 0.647

2007 Substantial reduction in fishing mortality

- 1.179 1.0473 1.076

2008 No increase in effort

- 1.238

2009 No increase in effort

-

Weights in ‘000 t. 1 Precautionary TAC for Subareas VII, VIII, IX, and X up to 1998 and the Division VIIa allocation of precautionary TAC from 1999. 2 Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits. 3 Preliminary. n/a = not available.


Recruitment (Age1)

0

1

2

3

4

5

6

1992 1994 1996 1998 2000 2002 2004 2006 2008

Year

mea

n st

anda

rdis

ed re

c (A

ge 1

)

SSB

0

0.5

1

1.5

2

2.5

3

1992 1994 1996 1998 2000 2002 2004 2006 2008

Year

Rel

ativ

e SS

B

Landings

0

1000

2000

3000

4000

5000

6000

1992 1994 1996 1998 2000 2002 2004 2006 2008

Year

Land

ings

(ton

nes)

Z

0

0.5

1

1.5

2

2.5

3

3.5

1992 1994 1996 1998 2000 2002 2004 2006 2008

Year

Rel

ativ

e M

ean

Z (2

-3)

SURBA valueempirical value NIGFS-Marempirical value NIGFS-Oct

Figure 5.4.3.1 Haddock in Division VIIa: Summary plots of landings, and trends in recruitment, total mortality

and spawning-stock biomass from the SURBA analysis which uses the NIGFS-Mar survey only. Dotted lines are ±1 s.e. Empirical Z values for the NIGFS-Mar and NIGFS-Oct are also shown for illustrative purposes.


Table 5.4.3.1 Nominal landings (t) of haddock in Division VIIa, 1984–2007, as officially reported to ICES. Country 1984 1985 1986 1987 1988 1989 1990 1991 1992 Belgium 3 4 5 10 12 4 4 1 8France 38 31 39 50 47 n/a n/a n/a 73

Ireland 199 341 275 797 363 215 80 254 251

Netherlands - - - - - - - - -

UK (England & Wales)1 29 28 22 41 74 252 177 204 244

UK (Isle of Man) 2 5 4 3 3 3 5 14 13

UK (N. Ireland) 38 215 358 230 196 … … … …

UK (Scotland) 78 104 23 156 52 86 316 143 114

Total 387 728 726 1,287 747 560 582 616 703 Country 1993 1994 1995 1996 1997 1998 1999 2000 Belgium 18 22 32 34 55 104 53 22 France 41 22 58 105 74 86 n/a 49

Ireland 252 246 320 798 1,005 1,699 759 1,238

Netherlands - - - 1 14 10 5 2

UK (England & Wales)1 260 301 294 463 717 1,023 1,479 1,061

UK (Isle of Man) 19 24 27 38 9 13 7 19

UK (N. Ireland) … … … … … … … …

UK (Scotland) 140 66 110 14 51 80 67 56

Total 730 681 841 1,453 1,925 3,015 2,370 2,447 Country 2001 2002 2003 2004 2005 2006 2007 Belgium 68 44 20 15 22 23 30* France 184 72 146 20 36 20 6*

Ireland 652 401 229 296 139 184 475*

Netherlands - - - - -

UK (England & Wales)1 1,238 551 248 421 344 419

UK (Isle of Man) 1 - - - - -

UK (N. Ireland) … … … … … … …

UK (Scotland) 86 47 31 9 6 9

United Kingdom 553*

Total 2,229 1,115 674 761 547 655 1064* *Preliminary. 11989–2007 Northern Ireland included with England and Wales. n/a = not available.


5.4.4 Haddock in Divisions VIIb–k

The updated exploratory assessment available for this stock does not change the perception of the stock and does not give reason to change the advice from 2007. The advice on this stock for the fishery in 2009 is therefore the same as the advice given in 2007 for the 2008 fishery: “Future catches and SSB will be highly dependent on the strength of incoming year classes and their discard mortality. No strong recruitment has been observed since 2002 and estimated recruitment for 2006 is the lowest since 1997. In this context the stock should be managed by ensuring that fishing effort is not allowed to increase.” Source of information Report of the Working Group on the Assessment of Southern Shelf Demersal Stocks, 30 April–6 May 2008 (ICES CM 2008/ACOM:12).

Year ICES Advice

Predicted catch corresp.

To advice

Agreed TAC1

Official Landings2

ICES landings

Discards ICES Catch

1987 Not dealt with 3.0 2.6 na 2.6 1988 Not dealt with 4.0 3.6 na 3.6 1989 Not dealt with 4.2 3.2 na 3.2 1990 Not dealt with 2.9 2.0 na 2.0 1991 Not dealt with 2.9 2.3 na 2.3 1992 Not dealt with 2.9 2.7 na 2.7 1993 Not dealt with 3.4 3.3 1.2 4.5 1994 Not dealt with 4.1 4.1 1.2 5.3 1995 Not dealt with 6 4.5 4.5 0.5 4.9 1996 Not dealt with 73 6.7 6.8 1.4 8.2 1997 Not dealt with 14 10.3 10.8 2.2 13.0 1998 Not dealt with 20 7.4 7.7 0.4 8.0 1999 Not dealt with 225 5.2 4.9 0.6 5.5 2000 No expansion of catches 16.65 6.7 7.4 7.3 14.7 2001 No expansion of catches 125 9.7 8.6 2.1 10.7 2002 No expansion of catches 8.0 9.35 7.1 6.4 7.0 13.4 2003 No expansion of catches 7.2 8.1855 8.2 8.1 8.2 16.4 2004 No increase in F - 9.6005 8.5 8.6 5.4 14.0 2005 No increase in effort - 11.5205 6.9 6.6 2.6 9.2 2006 No increase in effort - 11.5205 5.6 5.4 1.8 7.2 2007 No increase in effort - 11.5205 5.9 6.4 3.3 9.7 2008 No increase in effort - 11.5795 2009 Same advice as last year - -

Weights in ‘000 t. 1Applies to Subareas VII, VIII, IX, and X. 2Possible underestimates due to misreporting. 3Increased in-year to 14 000 t. 4Incomplete official statistics. 5Includes separate Division VIIa allocation.


Table 5.4.4.1 Nominal landings (t) of haddock in VIIb–k, officially reported to ICES and total landings used by the Working Group.

Official landings Un- Used by WG

Year Belgium France Ireland UK Others Total allocated Landings Discards Catch 1984 0 3328 646 403 549 4926 1985 4 2438 794 175 565 3976 1986 6 2279 317 245 86 2933 1987 12 2380 314 273 0 2979 1988 64 3275 275 409 0 4023 1989 117 3412 323 295 27 4174 1990 22 2110 461 318 31 2942 1991 18 1508 1020 250 97 2893 1992 21 1461 1073 306 26 2887 1993 51 1839 1262 256 0 3408 -60 3348 1193** 4541 1994 123 2788 908 240 17 4076 55 4131 1193** 5324 1995 189 2964 966 266 83 4468 2 4470 472 4942 1996 133 4527 1468 439 86 6653 103 6756 1394 8150 1997 246 6581 2789 569 85 10270 557 10827 2176 13003 1998 142 3674 2788 444 312 7360 308 7668 357 8025 1999 51 2725 2034 278 159 5247 -365 4882 648 5530 2000 90 3088 3066 289 123 6656 755 7411 7255 14666 2001 165 4842 3608 422 665 9702 -1070 8632 2050 10682 2002 132 4348 2188 315 106 7089 -686 6403 7024 13427 2003 118 5781 1867 393 82 8241 -95 8146 8234 16380 2004 136 6130 1715 313 159 8453 128 8581 5377 13958 2005 167 4174 2037 292 197 6867 -219 6648 2565 9213 2006 99 3190 1875 275 209 5648 -265 5383 1776 7159

2007* 118 3476 1914 383 3 5895 473 6368 3285 9653 * Preliminary. ** No discard data available, the average effort for 1995–1999 was used to estimate discards.


5.4.5 Whiting in Division VIIa (Irish Sea)

Single-stock exploitation boundaries The new data available for this stock do not change the perception of the stock and do not give reason to change the advice from 2007. The advice on this stock for the fishery in 2009 is therefore the same as the advice given in 2007 for the 2008 fishery: “On the basis of the stock status, ICES advises that catches of whiting[...] should be the lowest possible.” This advice will be updated in 2010.

Source of information Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 15–21 May 2008 (ICES CM 2008/ACOM:08). Year ICES



Predicted catch corresp. to single-stock boundaries

Agreed TAC

Official Landings

Disc.2 ICES Catch

1987 Reduce F 16.0 18.2 11.7 3.8 14.41988 No increase in F;

enforce mesh regulations 12.0 18.2 11.5 1.9 11.9

1989 F = Fhigh; enforce mesh regulations

11.0 18.2 11.3 2.0 13.4

1990 No increase in F; TAC 8.31 15.0 8.2 2.7 10.71991 Increase SSB to SSB(89) 6.41 10.0 7.4 2.7 9.91992 80% of F(90) 9.71 10.0 7.1 4.3 12.83

1993 70% of F(91) ~ 6 500 t 6.5 8.5 6.0 2.7 9.23

1994 Within safe biological limits - 9.9 5.6 1.2 7.93

1995 No increase in F 8.31 8.0 5.5 2.2 7.03

1996 No increase in F 9.81 9.0 5.6 3.5 8.03

1997 No advice given - 7.5 4.5 1.9 4.23

1998 20% reduction in F 3.84 5.0 3.4 1.3 3.53

1999 Reduce F below Fpa 3.54 4.41 2.0 1.1 2.83

2000 Reduce F below Fpa <1.64 2.64 1.1 2.1 2.93

2001 Lowest possible F ~0 1.39 1.1 1.0 1.73

2002 Lowest possible F ~0 1.00 0.7 0.7 1.53

2003 Lowest possible F ~0 0.50 0.5 n/a n/a2004 zero catch 0 0.514 0.2 n/a n/a2005 zero catch 0 0.514 0.2 n/a n/a2006 lowest possible

catch - 0.437 0.08 n/a n/a

2007 lowest possible catch

- 0.371 0.2 n/a n/a

2008 lowest possible catch

- 0.278

2009 Same advice as last year -

2010 Same advice as last year -

Weights in ‘000 t. 1Not including discards from the Nephrops fishery. 2From the Nephrops fishery. 3Including estimates of misreporting. 4Landings only, no discards included. n/a = not available.

69

Tab

le 5

.4.5

.1

Whi

ting

in D

ivis

ion

VII

a (I

rish

Sea)

. Nom

inal

cat

ch (t

) 198

8–20

07, a

s off

icia

lly re

porte

d to

ICES

and

Wor

king

Gro

up e

stim

ates

of d

isca

rds.

Cou

ntry

19

88

1989

19

90

1991

19

92

1993

19

94

1995

19

96

1997

B

elgi

um

90

92

142

53

78

50

80

92

80

47

Fran

ce

1,06

3 53

3 52

8 61

1 50

9 25

5 16

3 16

9 78

86

Ir

elan

d 4,

394

3,87

1 2,

000

2,20

0 2,

100

1,44

0 1,

418

1,84

0 1,

773

1,11

9 N

ethe

rland

s

17

14

U

K(E

ngl.

& W

ales

)a 1,

202

6,65

2 5,

202

4,25

0 4,

089

3,85

9 3,

724

3,12

5 3,

557

3,15

2 Sp

ain

U

K (I

sle

of M

an)

15

26

75

74

44

55

44

41

28

24

UK

(N. I

rela

nd)

4,62

1

U

K (S

cotla

nd)

107

154

236

223

274

318

208

198

48

30

UK

Tota

l hum

an c

onsu

mpt

ion

11,4

92

11,3

28

8,18

3 7,

411

7,09

4 5,

977

5,63

7 5,

465

5,58

1 4,

472

Estim

ated

Nep

hrop

s fis

hery

di

scar

ds u

sed

by th

e W

Gb

1,61

1 2,

103

2,44

4 2,

598

4,20

3 2,

707

1,17

3 2,

151

3,63

1 1,

928

Wor

king

Gro

up E

stim

ates

11

,856

13

,408

10

,656

9,

946

12,7

91

9,23

0 7,

936

7,04

4 7,

966

4,20

5


ICES

Adv

ice

2008

, Boo

k 5

70Tab

le 5

.4.5

.1 (c

td)

Cou

ntry

19

98

1999

20

00

2001

20

02

2003

20

04

2005

20

06

2007

* B

elgi

um

52

46

30

27

22

13

11

10

4.2

2.5

Fran

ce

81

150

59

25

33

29

8 13

3.

7 1.

95

Irel

and

1,26

0 50

9 35

3 48

2 34

7 26

5 96

94

55

.3

186.

7 N

ethe

rland

s 7

6 1

UK

(Eng

l. &

Wal

es)a

1,90

0 1,

229

670

506

284

130

82

47

21.7

3.

1 Sp

ain

85

U

K (I

sle

of M

an)

33

5 2

1 1

1 1

U

K (N

. Ire

land

)

UK

(Sco

tland

) 22

44

15

25

27

31

6

U

K

Tota

l hum

an c

onsu

mpt

ion

3,35

5 1,

989

1,13

0 1,

066

714

554

204

164

84.9

19

4.25

Estim

ated

Nep

hrop

s fis

hery

di

scar

ds u

sed

by th

e W

Gb

1,30

4 1,

092

2,11

8 1,

012

740

n/a

n/a

n/a

n/a

n/a

Wor

king

Gro

up E

stim

ates

3,

533

2,76

2 2,

880

1,74

5 1,

487

676

184

158

86

196

a 19

89 o

nwar

ds: N

orth

ern

Irel

and

incl

uded

with

Eng

land

and

Wal

es.

b B

ased

on

UK

(N. I

rela

nd) a

nd Ir

elan

d da

ta.

* Pr

elim

inar

y.



5.4.6 Whiting in Divisions VIIe–k

The new exploratory assessment available for this stock does not change the perception of the stock and does not give reason to change the advice from 2007.The advice on this stock for the fishery in 2009 is therefore the same as the advice given in 2007 for the 2008 fishery: “The current estimates of fishing mortality and SSB are uncertain, but SSB shows a decreasing trend while recruitment is low. In order to reverse this trend, ICES considers that fishing mortality should be reduced. However, ICES cannot quantify the required reduction in fishing mortality.” In addition, ICES offers the following consideration: surveys do indicate that the 2007 year class may be strong. management measures should be introduced in the Celtic Sea to reduce discarding of this year class in order to maximize its contribution to future yield and SSB. Source of information Report of the Working Group on the Assessment of Southern Shelf Demersal Stocks, 30 April–6 May 2008 (ICES CM 2008/ACOM:12. Year ICES

Advice Predicted catch corresp.

to advice Agreed TAC1

ICES Landings

1987 Status quo F; TAC 7.12 12.7 1988 Precautionary TAC 7.02 13.6 1989 Precautionary TAC 7.92 16.5 1990 No increase in F; TAC 8.42 14.1 1991 Precautionary TAC 8.02 13.5 1992 If required, precautionary TAC 8.02 12.4 1993 Within safe biological limits 6.62 22.0 16.3 1994 Within safe biological limits < 9.42 22.0 20.0 1995 20% reduction in F 8.23 25.0 22.7 1996 20% reduction in F 8.63 26.0 18.3 1997 At least 20% reduction in F < 7.34 27.0 20.5 1998 At least 20% reduction in F < 8.24 27.0 19.2 1999 No increase in F 12.44 25.0 19.9 2000 17% reduction in F < 13.14 22.2 14.9 2001 No increase in F 13.54 21.0 12.8 2002 No increase in F 27.74 31.7 13.3 2003 No increase in F 20.24 31.7 10.6 2004 No increase in F 14.0 27.0 10.0 2005 No increase in F 10.6 21.6 12.5 2006 No increase in F 10.8 19.9 9.5 2007 No increase in F - 19.9 8.9 2008 Reduction in F - 19.9 2009 Same advice as last year -

Weights in t. 1 TAC covers Subarea VII (except Division VIIa). 2 For the VIIf+g stock component. 3 For the VIIf–h stock component. 4For the VIIe–k stock component.


Table 5.4.6.1 Whiting in Divisions VIIe–k. Nominal landings (t) as reported to ICES, and total landings as used by the ICES Working Group.

1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007a

Belgium 130 158 160 107 112 159 295 317 304 111 145 228 205 268 449 479 448 194 171 149 129 180 218 128 127DenmarkFrance 7,572 4,024 7,819 7,763 9,773 10,947 19,771 19,348 10,006 9,620 11,285 13,535 13,400 9,936 11,370 11,711a 16,418b 9,077a 7,203a 7,435a 5,897 4,811 5,784 4,649 2,972Germany 14Ireland 1,511 1,227 2,241 1,309 1,518 2,036 1,651 1,764 1,403 1,875 3,630 5,053 6,077 6,115 6,893 5,226 5,807 4,795 5,008 5,332 4093 4,215 5,709 4,521 4,750Netherlands 398 124 8 1 5 4 9 18 60 40Spain 4 31 24 53 21 11 9 12 76 56 70UK (E/W/NI) 1,192 986 751 910 1,098 1,632 1,326 1,829 2,023 1,393 1,776 1,624 1,803 1,724 1,742 1,706 1,344 1,249 943 843 758 586 471 403 571UK(Scotland) 1 33 32 20 41 16 23 23 34 42 68 3 2 11 12 5 7 6United KingdomChannel Islands 2 2 2 1 1 3 2 3 3 1 4

Total 10,405 6,793 10,973 10,215 12,503 14,775 23,076 23,290 13,756 13,054 16,852 20,463 21,513 18,116 20,520 19,247 24,043 15,331 13,353 13,788 10,895 9,893 12,298 9,817 8,420

Unallocated 1,376 3,192 -135 -263 149 353 -6,535 -9,184 -248 -690 -532 -429 1,165 144 12 -2 -4,126 -466 -569 -509 -312 78 207 -302 436

Total as used byWorking Group 11,781 9,985 10,838 9,952 12,652 15,128 16,541 14,106 13,508 12,364 16,320 20,034 22,678 18,260 20,532 19,245 19,917 14,865 12,784 13,279 10,583 9,971 12,505 9,515 8,856

a: Preliminaryb: Preliminary, Reported as VIIb-k Table 5.4.6.2 Nominal landings (t) of whiting in Divisions VIIb,c (included in the TAC area). Country 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 France 57 76 65 37* …1* 109 114 113 92 63 129 62 25Ireland 1,894 1,233 403 323 206 563 357 386 423 135 65 49 100Netherlands - - - - - - 2 - 3 2 Spain + + - 27 1 4 - 6 31 18 19UK(E/W/NI) 24 96 75 49 10 6 5 4 5 1 11 5 1UK(Scotland) 71 17 4 27 - 19 1 + - 11 Total 2,046 1,422 547 463 217 701 479 509 523 230 236 135 127

1See VIIg-k.


5.4.7 Plaice in Division VIIa (Irish Sea)





Comment

Full reproductive capacity

Harvested sustainably

Underfished Not defined

Based on the most recent estimate of SSB (in 2008) and fishing mortality (in 2007) ICES classifies the stock as having full reproductive capacity and being harvested sustainably. The SSB in 2008 was above Bpa. Fishing mortality has been declining since the late 1980s and has been below Fpa since 1998. Management objectives There are no explicit management objectives for this stock. Reference points Type Value Technical basis

Blim Not defined. There is no biological basis for defining Blim as the stock–recruitment data are uninformative.

Bpa 3 100 t Bpa = Bloss. Flim Not defined. There is no biological basis for defining Flim as Floss is poorly defined. Precautionary

approach Fpa 0.45 Fpa = Fmed in a previous assessment, and in long-term considerations.

This is considered to provide a high probability that SSB remains above Bloss in the long term.

Targets Fy Not defined. (unchanged since: 1998) Yield and spawning biomass per Recruit F-reference points: Fish Mort Yield/R SSB/R Ages 3–6 Average last 3 years 0.13 0.19 1.39 Fmax Not defined F0.1 0.14 0.19 1.32 Fmed 0.42 0.22 0.54 A candidate for a reference point consistent with high long-term yield and low risk of depleting the productive potential of the stock is around F0.1 (= 0.14). Single-stock exploitation boundaries Exploitation boundaries in relation to high long-term yield, low risk of depletion of production potential and considering ecosystem effects The current fishing mortality (2007) is estimated to be 0.09, which is below the rate expected to lead to high long-term yields and low risk of stock depletion. There would be little gain to the long-term yield by increasing fishing mortalities above current levels. Fishing at F0.1 corresponds to landings in 2009 of 1430 t. Exploitation boundaries in relation to precautionary limits Fishing mortality should be kept below Fpa (0.45). This corresponds to catches of less than 3960 t in 2009 and will maintain SSB above Bpa in 2010.


Conclusion on exploitation boundaries In the present situation with a stock that is well above Bpa and fishing mortality below Fpa and below F0.1, there is little gain to the long-term yield by increasing fishing mortality above current levels. Hence, ICES recommends that landings in 2009 be limited to no more than 1430 t. Short-term implications Outlook for 2009 Basis: F(2008) = Fsq = mean F(05–07) = 0.13; R08–10 = GM90–05 = 8.6 million; SSB(2009) = 9.72; landings (2008) = 1.24.

Management considerations Plaice and sole fisheries in the Irish Sea are less closely linked than in other areas. Plaice are taken in a mixed demersal fishery comprising otter trawl and beam trawl gears. The otter trawl fleet seasonally targets plaice, but has declined markedly in the last decade. The beam trawl fleet principally targets sole. The regulations affecting plaice and other demersal stocks in Division VIIa remain linked to those implemented under the Irish Sea cod recovery plan. The high level of discarding (up to 80% by number) in this fishery indicates a mismatch between the minimum landing size and the mesh size of the gear being used. Any measures to reduce discards will result in increased future yield. Management plan evaluations There is no management plan for plaice in the Irish Sea. Impacts of fisheries on the ecosystem A large proportion of the plaice catch is caught by beam trawl fisheries. Beam trawling, especially using chain-mat gear, is known to have a significant impact on the benthic communities, although less so on soft substrates and in areas which have been historically exploited by this fishing method. Some beam trawlers are using benthic drop-out panels that release about 75% of benthic invertebrates from the catches. Full square mesh codends are being tested in order to reduce the capture of benthos further and improve the selection profile on gadoids.

Rationale TAC(2009) (1) Basis F(2009) SSB(2010) %SSB change %TAC change

Zero catch 0.00 F=0 0.00 11.49 18% -100% Status quo 1.30 Fsq 0.13 10.25 5% -29%

High long-term yield 1.43 F(long-term yield) 0.14 10.13 4% -23%

0.14 Fsq *0.1 0.01 11.36 17% -93% 0.34 Fsq *0.25 0.03 11.17 15% -82% 0.67 Fsq *0.5 0.06 10.85 12% -64% 0.90 Fsq *0.68 0.09 10.63 9% -51% 0.99 Fsq *0.75 0.10 10.54 9% -46% 1.30 Fsq *1 0.13 10.25 5% -29%

Status quo

1.42 Fsq *1.1 0.14 10.13 4% -23% Precautionary

approach 3.96 Fpa = Fsq *3.5 0.45 7.73 -20% 114%

(1) It is assumed that the TAC will be implemented and that the landings in 2009 therefore correspond to the TAC. All weights in thousand tonnes. Shaded scenarios are not considered consistent with the precautionary approach.


Factors affecting the fisheries and the stock Regulations and their effects Technical measures in force are minimum mesh sizes and minimum landing size (27 cm). A decrease in the minimum landing size would not resolve the discarding problem as the market for small plaice is generally poor. The closures of cod spawning-grounds that have been in force since 2000 are unlikely to have had a significant impact on the plaice fishery. In 2000 the closure covered the Western and Eastern Irish Sea. Since then, closure has been mainly in the western part, whereas the main plaice fishery has taken place in the eastern part of the Irish Sea. Changes in fishing technology and fishing patterns Fishing behavior has changed in response to high fuel prices. There has been a switch by Irish trawlers to reduce gear size in some cases by as much as 20%. There is also evidence of larger vessels switching from twin-rigging back to single rigging to reduce fuel consumption. In the 24 m+ range vessels are now working at around 50–60% of their total power in a bid to reduce fuel costs. This implies a reduction in catch rates, and may also effect the length distribution of the catches. Around 10% of the Belgian beam trawlers were decommissioned between August 2005 and November 2006 (having its full impact from 2007 onwards). Impacts of the environment on the fish stock There is no specific information of impacts of the environment on this stock. Scientific basis Data and methods The assessment is based on a catch-at-age analysis, using landings data and data from three scientific surveys. Discard levels are substantial in the fishery, but the time-series is too short to be incorporated into the assessment. Uncertainties in assessment and forecast Discard sampling studies have indicated discarding up to 80% by number. Discards are not included in the assessment. The assessment may thus be biased, but it is not known to what extent. There are conflicting signals in the survey and commercial tuning fleet indices. The commercial tuning fleet indices are not used in the assessment as they give inconsistent trends. The assessment is strongly influenced by survey trends and the retrospective analysis indicates that the assessment overestimates stock size. Comparison with previous assessment and advice Trends in SSB and fishing mortality are consistent with last year’s assessment. F values for 2006 have been revised upwards marginally, and SSB in 2007 has been revised downwards by 30%. Last year the advice was based on Fpa. This year the advice is based on F0.1 because there is no long-term gain in increasing fishing mortality above F0.1. Sources of information Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 15–21 May 2008 (ICES CM 2008/ACOM:08). Cotter, J., Armstrong, M., Woods, T., Dann, J., White, P., and Keable, J. 2004. Programme 8: Gear selectivity in the Irish Sea Part 1: Eastern Irish Sea plaice fishery, 2004/05 Fisheries Science Partnership, November 2004. 19 pp. www.cefas.co.uk.

ICES

Adv

ice

2008

, Boo

k 5

76

Yea

r IC

ES

Adv

ice

Sing

le-s

tock

ex

ploi

tatio

n bo

unda

ries 2

Pred

icte

d ca

tch

corre

sp.

to a

dvic

e

Pred

icte

d ca

tch

corre

spon

ding

to

singl

e-sto

ck

boun

darie

s

Agr

eed

TAC

Offi

cial

la

ndin

gs

ICES

La

ndin

gs

1987

F

high

; no

long

-term

gai

ns in

incr

easin

g F

5.

0

5.0

5.6

6.2

1988

N

o in

crea

se in

F

4.

8

5.0

4.4

5.0

1989

80

% o

f F(8

7); T

AC

5.

8

5.8

4.2

4.4

1990

H

alt d

eclin

e in

SSB

; TA

C

5.1

5.

1 4.

0 3.

3 19

91

Rebu

ild S

SB to

SSB

(90)

; TA

C

3.3

4.

5 2.

8 2.

6 19

92

70%

of F

(90)

3.0

3.

8 3.

2 3.

3 19

93

F =

0.55

~ 2

800

t

2.8

2.

8 2.

0 2.

0 19

94

Long

-term

gai

ns in

dec

reas

ing

F

<3.7

3.1

2.1

2.1

1995

Lo

ng-te

rm g

ains

in d

ecre

asin

g F

2.

41

2.8

2.0

1.9

1996

N

o lo

ng-te

rm g

ain

in in

crea

sing

F

2.5

2

.45

1.9

1.7

1997

N

o ad

vice

-

2.1

2.0

1.9

1998

N

o in

crea

se in

F

2.

4

2.4

1.8

1.8

1999

K

eep

F be

low

Fpa

2.4

2.

4 1.

6 1.

6 20

00

Kee

p F

belo

w F

pa

<2

.3

2.

4 1.

4 1.

4 20

01

Kee

p F

belo

w F

pa

<2

.4

2.

0 1.

5 1.

5 20

02

Kee

p F

belo

w F

pa

<2

.8

2.

4 1.

5 1.

6 20

03

No

incr

ease

in F

1.9

1.

675

1.6

1.6

2004

F<F p

a

1.6

1.34

1.

1 1.

1

2005

F<F p

a

2.97

1.

608

1.3

1.3

2006

F<F p

a

5.9

1.60

8 0.

9 0.

9

2007

F<F p

a

6.5

1.84

9 0.

8 0.

8

2008

F<F p

a

5.2

1.84

9

2009

N

o lo

ng-te

rm g

ains

in in

crea

sing

F ab

ove

F 0.1

F<

F 0.1

1.

4

Wei

ghts

in ‘0

00 t.

1 C

atch

at s

tatu

s quo

F.

2 S

ingl

e-st

ock

boun

dary

, the

exp

loita

tion

of th

is st

ock

shou

ld b

e co

nduc

ted

in th

e co

ntex

t of m

ixed

fish

erie

s pro

tect

ing

stoc

ks o

utsi

de sa

fe b

iolo

gica

l lim

its.



Figure 5.4.7.1 Plaice in Division VIIa (Irish Sea). Landings, fishing mortality, recruitment, and SSB.

Landings

01

2345

67

1964 1969 1974 1979 1984 1989 1994 1999 2004

Land

ings

in 1

000

t

Fishing Mortality

0.0

0.2

0.4

0.6

0.8

1.0

1964 1969 1974 1979 1984 1989 1994 1999 2004

F(ag

es 3

-6)

F

Fpa

Recruitment (age 2)

05

10152025

3035

1964 1969 1974 1979 1984 1989 1994 1999 2004

Rec

ruitm

ent i

n m

illio

ns


0

2

4

6

8

10

12

1964 1969 1974 1979 1984 1989 1994 1999 2004

SSB

in 1

000

t

SSB

Bpa


Figure 5.4.7.2 Plaice in Division VIIa (Irish Sea). Stock and recruitment, yield, and SSB per recruit.

Stock - Recruitment

0

5

10

15

20

25

30

35

0 2 4 6 8 10 12

SSB in 1000 t

Recr

uitm

ent (

age

2) in

m

illio

ns SSB-Rec.

Bpa


0

0.05

0.1

0.15

0.2

0.25

0 0.5 1 1.5 2


Yie

ld (d

ashe

d lin

e)

00.51

1.522.53

3.54

SSB

(lin

e)Precautionary Approach Plot

Period 1964-2007

0

2

4

6

8

10

12

0.0 0.2 0.4 0.6 0.8 1.0Fishing Mortality (ages 3-6)

SSB

in 1

000

t

F-SSB

2007

Fpa

Bpa


Figure 5.4.7.3 Plaice in Division VIIa (Irish Sea). Comparison of current assessment with previous assessments.

Note: Recruitment age was change from 1 to 2 years old in 2008.

Plaice in Division VIIa (Irish Sea)

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

16.0

1990 1995 2000 2005

SSB ('000 tonnes)

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

1990 1995 2000 2005


0

5

10

15

20

25

1990 1995 2000 2005



Table 5.4.7.1 Plaice in Division VIIa (Irish Sea). Landings (tonnes) by year and country.

Country 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 1

Belgium 321 128 332 327 3443 459 327 275 325 482 636 628 431 566 345 194

France 42 19 13 10 11 8 8 5 14 91 8 7 2 9 2 2

Ireland 1,355 654 547 557 538 543 730 541 420 378 370 490 328 272 176 193

Netherlands - - - - 69 110 27 30 47 - - - - - - -

UK (Eng.&Wales)2 1,381 1,119 1,082 1,050 878 798 679 687 610 607 569 409 369 422 411 412

UK (Isle of Man) 24 13 14 20 16 11 14 5 6 1 1 1 0 0 0 0

UK (N. Ireland) … … … … … … … … … … … … … … … …

UK (Scotland) 70 72 63 60 18 25 18 23 21 11 7 9 4 1 0 0

UK (Total)

Total 3,193 2,005 2,051 2,024 1,874 1,954 1,803 1,566 1,443 1,488 1,591 1,544 1,134 1,270 934 801

Discards - - - - - - - - - - - - - - - -

Unallocated 74 -9 15 -150 -167 -83 -38 34 -72 -15 31 10 -19 226 -2 -3

3,267 1,996 2,066 1,874 1,707 1,871 1,765 1,600 932 8041Provisional.2Northern Ireland included with England and Wales.

{UK (Total) excludes Isle of Man data}.

1,559 1,143 1,281

Total figures used by the Working Group for stock assessment 1,371 1,473 1,623


Table 5.4.7.2 Plaice in Division VIIa (Irish Sea).


1964 21660 8274 2879 0.304 1965 29090 9367 3664 0.365 1966 15080 9887 4268 0.425 1967 13590 10100 5059 0.508 1968 10900 9563 4695 0.481 1969 12510 9023 4394 0.461 1970 18550 8314 3583 0.403 1971 17280 8137 4232 0.640 1972 11820 8960 5119 0.612 1973 8746 7019 5060 0.766 1974 11710 5433 3715 0.769 1975 11510 5676 4063 0.776 1976 9664 3905 3473 0.923 1977 15010 3005 2904 0.834 1978 16170 3543 3231 0.735 1979 20090 4155 3428 0.612 1980 18190 4625 3903 0.700 1981 13550 5412 3906 0.576 1982 7387 5153 3237 0.549 1983 18740 4539 3639 0.708 1984 18770 5512 4241 0.567 1985 19800 6384 5075 0.588 1986 14380 7247 4806 0.580 1987 17590 6884 6220 0.815 1988 18820 7339 5005 0.753 1989 11500 6690 4372 0.580 1990 6606 5749 3275 0.559 1991 10240 4809 2554 0.451 1992 9047 4685 3267 0.720 1993 9910 4027 1996 0.536 1994 8286 3933 2066 0.490 1995 7179 3796 1874 0.438 1996 6750 4018 1707 0.381 1997 8433 3728 1871 0.500 1998 8630 3923 1765 0.439 1999 7661 3872 1600 0.381 2000 7617 4077 1371 0.290 2001 9461 4729 1473 0.315 2002 8965 5170 1623 0.302 2003 10870 6071 1559 0.262 2004 8746 6136 1143 0.165 2005 10690 6802 1281 0.176 2006 9258 7629 934 0.119 2007 6680 7676 804 0.086 2008 8591 1 9030 2

Average 12572 6089 3189 0.514

1 GM90–05. 2 Short-term forecast prediction of SSB.


5.4.8 Celtic Sea plaice (Divisions VIIf and g)





Comment


Undefined Overfished No agreed target

Based on the most recent estimates of SSB, ICES classifies the stock as having reduced reproductive capacity. SSB peaked in 1988–1990, following a series of good year classes, then declined rapidly and has since 2002 been below or around Blim. Fishing mortality has fluctuated around an average level (0.60) for the entire time-series but has declined since 2004. Recruitment was relatively high in most years during the 1980s, but has been lower since then. Some very weak year classes have occurred since the late 1990s. Management objectives There are no specific management objectives for this stock. Reference points Type Value Technical basis

Blim 1 100 t Blim=Bloss, the lowest observed spawning-stock biomass. Bpa 1 800 t Bpa= Blim * 1.64. Biomass above this affords a high probability of

maintaining SSB above Blim, taking into account the uncertainty of assessments.

Flim Not defined.


Fpa Not defined. Targets Fy Not defined. (unchanged since: 1998) Yield and spawning biomass per Recruit F-reference points:


A candidate for a target reference point consistent with taking high long-term yields and achieving a low risk of depleting the productive potential of the stock may be identified in the range of F0.1 (0.12) and Fmax (0.27). Single-stock exploitation boundaries Exploitation boundaries in relation to high long-term yield, low risk of depletion of production potential and considering ecosystem effects The current fishing mortality (2007) is estimated at 0.40, which is above the range that would lead to high long-term yields and low risk of stock depletion. Exploitation boundaries in relation to precautionary considerations A 75% reduction in F is needed to increase SSB to around Bpa in 2010. This corresponds to landings of less than 170 t in 2009.


Short-term implications Outlook for 2009 Basis: F(2008) = Fsq = mean F(05–07) = 0.41; R = GM89–06 = 2.89 million; SSB(2008) = 1.24; SSB(2009) = 1.3; landings (2008) = 0.52.

Rationale TAC(2009) Basis F(2009) SSB(2010) %SSB change 1

% TAC change 2

Zero catch 0.0 F=0 0.0 1.96 46% -100%


0.07 Fsq *0.1 0.04 1.90 41% -86%

Achieve Bpa 0.17 Fsq *0.25 0.11 1.80 34% -66%

0.31 Fsq *0.5 0.21 1.67 24% -37%

0.45 Fsq *0.75 0.31 1.54 15% -9%

0.52 Fsq *0.9 0.37 1.47 9% 6%

Status quo 0.57 Fsq *1 0.41 1.43 6% 16%

0.62 Fsq *1.1 0.45 1.38 3% 26%

0.68 Fsq *1.25 0.51 1.32 -2% 39% All weights in ‘000 tonnes. Shaded scenarios are not considered consistent with the precautionary approach. 1 SSB 2010 relative to SSB 2009. 2 TAC 2009 relative to TAC 2008. Management considerations Since 2000 the estimated landings have been below the TACs. Nevertheless, according to the catch forecast the predicted landings in 2008 at status quo fishing mortality is 7% higher than the agreed TAC for 2008. Discard rates are high for this stock in some seasons/fleets. The high level of discarding indicated in this mixed fishery would suggest a mismatch between the mesh size employed and the size of the fish landed. Increases in the mesh size of the gear should result in fewer discards and in increased yield from the fishery. The use of larger-mesh gear should be encouraged in this fishery in instances where mixed fishery issues allow for it. Ecosystem considerations Beam trawling, especially using chain-mat gear, is known to have a significant impact on the benthic communities, although less so on soft substrates and in areas which have been historically exploited by this fishing method. Factors affecting the fisheries and the stock The main fishery occurs in the spawning area off the north Cornish coast, at depths greater than 40 m, about 20 to 25 miles offshore. Although plaice are taken throughout the year, the larger landings occur during February–March after the peak of spawning, and again in September. Recent increases in fuel costs are thought to have restricted the range of some fleets and may have resulted in a reduction in effort in Divisions VIIfg. Regulations and their effects Plaice in the Bristol Channel and Celtic Sea (ICES Divisions VIIf and VIIg) is managed by TAC and technical measures. Technical measures in force for this stock are minimum mesh sizes, minimum landing size, and restricted areas for certain classes of vessels. Technical regulations regarding allowable mesh sizes for specific target species, and associated minimum landing sizes, came into force on 1 January 2000. The minimum landing size for plaice in Divisions VIIf,g is 27 cm.


Since 2005, ICES rectangles 30E4, 31E4, and 32E3 have been closed during the first quarter (Council Regulations 27/2005, 51/2006, and 41/2007) with the intention of reducing fishing mortality on cod. There is evidence that this closure has redistributed effort to other areas. Many vessels (particularly beam trawlers from the UK and Belgium) fished close to the borders of the closed rectangles during the closure, and fished intensively inside the rectangles when they were re-opened. Information from the UK shows that plaice can be caught in areas outside of the closed area with the same catch rates. Therefore the closed area probably had little impact on the fishing mortality on plaice. Scientific basis Data and methods The assessment is based on landings, one survey index, and two commercial cpue series. Information from the fishing industry The UK Fisheries Science Partnership investigations conducted in the Eastern Celtic Sea and Bristol Channel during 2005 confirmed that discards of plaice in the Celtic Sea were substantial. Uncertainties in assessment and forecast Discards are substantial and can range from 30% to 70% in number (mainly below the minimum landing size). Due to the short time-series discards are not included. There is a retrospective bias of overestimation of SSB and underestimation of fishing mortality. Recent forecasts for this stock have been overly optimistic, probably due to this bias problem. Comparison with previous assessment and advice SSB in 2007 has been revised downwards by 7% and F in 2006 upwards by 29%. The advice for a reduction in F to rebuild SSB above Bpa is consistent with last year’s advice. Source of information Report of the Working Group on the Assessment of Southern Shelf Demersal Stocks, 30 April–6 May 2008 (ICES CM 2008/ACOM:12).


Year ICES



To advice

Predicted catch


stock boundaries

Agreed TAC

Official landings

ICES Landings

1987 TAC not to be restrictive on other species

- 1.8 1.91 1.90


- 2.5 2.19 2.12


- 2.5 2.58 2.15

1990 F likely to be F(88) ~1.9 1.9 2.22 2.08 1991 F likely to be F(89) ~1.7 1.9 1.83 1.50 1992 No long-term gains in

increasing F - 1.5 1.36 1.19

1993 No long-term gains in increasing F

- 1.4 1.30 1.11


- 1.4 0.98 1.07

1995 No increase in F 1.29 1.4 0.96 1.03 1996 20% reduction in F 0.93 1.1 0.98 0.95 1997 20% reduction in F 1.10 1.1 1.26 1.22 1998 20% reduction in F 1.00 1.1 1.15 1.07 1999 35% reduction in F 0.67 0.9 0.66 0.97 2000 30% reduction in F 0.70 0.80 0.72 0.72 2001 40% reduction in F 0.60 0.76 0.68 0.71 2002 At least 35% reduction in F 0.68 0.68 0.62 0.65 2003 At least 40% reduction in F <0.66 0.66 0.56 0.59 2004 1 F < 0.10 or Recovery

plan 1 <0.21 0.56 0.49 0.51

2005 1 70% Reduction in F or Recovery plan

1 <0.25 0.48 0.40 0.39

2006 1 50% reduction in F or Recovery plan

1 <0.40 0.48 0.41 0.40

2007 1 50% reduction in F or Recovery plan

1 <0.38 0.42 0.38 0.41

2008 1 60% reduction in F 1 <0.24 0.49 2009 1 75% reduction in F 1 <0.17 Weights in ‘000 t. 1 Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits.


Figure 5.4.8.1 Celtic Sea plaice (Divisions VIIf and g). Landings, fishing mortality, recruitment, and SSB.

Landings

0

0.5

1

1.5

2

2.5

1977 1982 1987 1992 1997 2002 2007

Land

ings

in 1

000

t

Fishing Mortality

0.00.10.20.30.40.50.60.70.8

1977 1982 1987 1992 1997 2002 2007

F(ag

es 3

-6)

Recruitment (age 1)

02

468

10

1214

1977 1982 1987 1992 1997 2002 2007

Rec

ruitm

ent i

n m

illio

ns


00.5

11.5

22.5

33.5

44.5

1977 1982 1987 1992 1997 2002 2007

SSB

in 1

000

t

SSB

Blim

Bpa


Figure 5.4.8.2 Celtic Sea plaice (Divisions VIIf and g). Stock and recruitment; yield, and SSB per recruit.

Stock - Recruitment

0

2

4

6

8

10

12

14

0 1 2 3 4 5

SSB in 1000 t

Rec

ruitm

ent (

age

1) in

m

illio

ns SSB-Rec.

Blim

Bpa


0

0.05

0.1

0.15

0.2

0.25

0 0.2 0.4 0.6 0.8 1


Yiel

d (d

ashe

d lin

e)

00.511.522.533.544.55

SSB

(lin

e)


00.5

11.5

22.5

33.5

44.5

0.0 0.2 0.4 0.6 0.8


SSB

in 1

000

t

F-SSB

2007

Blim

Bpa


Figure 5.4.8.3 Celtic Sea plaice (Divisions VIIf and g). Comparison of current assessment with previous

assessments.

Celtic Sea plaice (Divisions VIIf and g)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

1990 1995 2000 2005

SSB ('000 tonnes)

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

1990 1995 2000 2005


0

2

4

6

8

10

12

14

1990 1995 2000 2005


ICES

Adv

ice

2008

, Boo

k 5

89

Tab

le 5

.4.8

.1

Tabl

e 4.

4.1

Plai

ce in

div

isio

ns V

IIf&

gN

omin

al la

ndin

gs (t

) as

repo

rted

to IC

ES, a

nd to

tal l

andi

ngs

as u

sed

by th

e w

orki

ng g

roup

Nat

iona

l lan

ding

s as

est

imat

ed b

y th

e w

orki

ng g

roup

197

7 - 1

985;

as

repo

rted

to IC

ES a

nd to

tal l

andi

ngs

as u

sed

by th

e w

orki

ng g

roup

198

6 on

war

ds

1977

1978

1979

1980

1981

1982

1983

1984

1985

1986

1987

1988

1989

1990

1991

Bel

gium

214

196

171

372

365

341

314

283

357

665

581

617

843

794

836

UK

(Eng

l. &

Wal

es)

150

152

176

227

251

196

279

366

466

529

496

629

471

497

392

Fran

ce36

552

746

770

669

756

853

255

849

387

870

872

110

8976

744

4Ire

land

280

4961

6419

848

7291

302

127

226

180

160

155

N. I

rela

nd1

Net

herla

nds

9Sc

otla

nd0

00

70

00

00

11

Tota

l75

787

586

313

7313

7713

0311

7312

7914

0723

8419

1221

9425

8322

1918

27

Una

lloca

ted

00

00

00

-27

-69

345

-693

-11

-78

-432

-137

-326

Tota

l as

used

by

WG

757

875

863

1373

1377

1303

1146

1210

1752

1691

1901

2116

2151

2082

1501

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

Bel

gium

542

350

346

410

594

540

371

224

241

248

221

212

168

172

194

UK

(Eng

l. &

Wal

es)

290

251

284

239

258

176

170

134

136

105

127

8755

8861

Fran

ce37

329

825

424

632

929

828

726

218

616

514

513

210

668

Irela

nd89

8270

8378

135

115

7645

7951

4544

4858

N. I

rela

ndN

ethe

rland

sSc

otla

nd9

12

Tota

l rep

orte

d13

0398

295

697

812

5911

4965

672

168

461

856

448

939

941

438

1

Una

lloca

ted

-189

8872

-26

-42

-82

312

-330

2830

21-1

0-1

025

Tota

l as

used

by

WG

1114

1070

1028

952

1217

1067

968

718

714

646

594

510

389

404

406



Table 5.4.8.2 Celtic Sea plaice (Divisions VIIf and g).

Year Recruitment SSB Landings Mean F Age 1 Ages 3-6 thousands tonnes tonnes

1977 3582 1170 757 0.632 1978 4965 1010 875 0.673 1979 8005 1323 863 0.666 1980 5550 1789 1373 0.541 1981 2050 1793 1377 0.488 1982 3549 2055 1303 0.630 1983 9267 1941 1146 0.551 1984 10231 2304 1210 0.667 1985 7922 2646 1752 0.500 1986 8232 2832 1691 0.524 1987 12081 3272 1901 0.659 1988 7312 3835 2116 0.621 1989 3064 3178 2151 0.652 1990 2187 3433 2082 0.753 1991 4787 2804 1501 0.591 1992 4504 2555 1188 0.512 1993 2900 2054 1114 0.454 1994 3959 1965 1070 0.528 1995 5252 2003 1028 0.667 1996 3840 1813 952 0.553 1997 3351 1784 1217 0.716 1998 2246 1675 1067 0.652 1999 2209 1379 968 0.723 2000 3250 1183 718 0.597 2001 2342 1263 714 0.491 2002 2056 1074 646 0.698 2003 1375 1064 594 0.615 2004 2408 897 510 0.605 2005 3072 859 389 0.448 2006 2247 943 404 0.380 2007 2906 999 406 0.404 2008 2891* 1238

Average 4487 1879 1132 0.587 * GM89–06.


5.4.9 Plaice in Division VIIe (Western Channel)

The new assessment available for this stock does not change the perception of the stock and does not give reason to change the advice from 2007. The stock remains below Bpa. The advice for the fishery in 2009 is therefore the same as the advice given in 2007 for the 2008 fishery: “Given the low stock size, recent poor recruitment, high fishing mortality, the uncertainty in the assessment, and the inability to reliably forecast catch, ICES recommends a substantial reduction in catch until the estimate of SSB is above Bpa or other strong evidence of rebuilding is observed.” Source of information Report of the Working Group on the Assessment of Southern Shelf Demersal Stocks, 30 April–6 May 2008 (ICES CM 2008/ACOM:12). Year ICES


Predicted catch

corresp. to advice

Predicted catch

corresponding to single-stock

boundaries

Agreed TAC1

Official Landings

ICES Landings

1987 Precautionary TAC 6.8 8.3 1.92 1.961988 Precautionary TAC 6.9 9.96 2.33 2.461989 No increase in effort; TAC 11.7 11.7 2.25 2.361990 No increase in F; TAC 10.7 10.7 1.99 2.591991 50% reduction in F in VIIe 8.8 10.7 1.65 1.851992 Sq. F gives over mean SSB 2.02 9.6 1.56 1.621993 Not outside safe biological limits - 8.5 1.44 1.421994 Within safe biological limits - 9.1 1.29 1.161995 No increase in F 1.42 8.0 1.16 1.031996 60% reduction in F 0.62 7.5 1.14 1.041997 60% reduction in F 0.512 7.09 1.37 1.321998 60% reduction in F 0.52 5.7 1.24 1.131999 Reduce F below Fpa 1.12 7.4 0.96 1.302000 Reduce F below Fpa < 1.082 6.5 1.29 1.282001 Reduce F below Fpa < 0.932 6.0 1.11 1.112002 Reduce F below Fpa < 0.892 6.7 1.25 1.262003 At least 50% reduction in F < 0.532 5.97 1.24 1.282004 3 A 55%

reduction in F3 <0.660 6.06 1.14 1.21

2005 A 64% reduction in F

<0.580 5.15 1.13 1.20

2006 Substantial reduction in

catch

- 5.15 1.24 1.31


catch

- 5.05 0.88 1.01


catch

- 5.05

2009 Same advice as last year Substantial reduction in

catch

Weights in ‘000 t. 1TACs for Divisions VIId,e. 2For Division VIIe only. 3 Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits.


Table 5.4.9.1 Plaice in Division VIIe. Nominal landings (t) in Division VIIe, as used by Working Group.

Year Belgium Denmark France UK (Engl. & Wales)

Others Total reported

Unallocated1 Total

1976 5 - 3 323 312 - 640 - 6401977 3 - 3 336 363 - 702 - 7021978 3 - 3 314 467 - 784 - 7841979 2 - 3 458 515 - 975 2 9771980 23 - 3 325 609 9 966 113 10791981 27 - 537 953 - 1517 -16 15011982 81 - 363 1109 - 1553 135 16881983 20 - 371 1195 - 1586 -91 14951984 24 - 278 1144 - 1446 101 15471985 39 - 197 1122 - 1358 83 14411986 26 - 276 1389 - 1 1691 119 18101987 68 - 435 1419 - 1922 36 19581988 90 - 584 1654 - 2328 130 24581989 89 - 448 1 1708 2 2247 111 23581990 82 2 N/A 2 1885 18 1987 606 25931991 57 - 251 1 1323 16 1647 201 18481992 25 - 419 1102 14 1560 64 16241993 56 - 284 1080 24 1444 -27 14171994 10 - 277 998 3 1288 -132 11561995 13 - 288 857 - 1158 -127 10311996 4 - 279 855 - 1138 -94 10441997 6 - 329 1038 1 1374 -51 13231998 22 - 327 4 892 1 1242 -111 11311999 12 - 194 1 947 - 1153 118 12712000 4 - 360 926 + 1290 -9 12812001 12 - 303 797 - 1112 -6 11062002 27 - 238 978 + 1253 4 12572003 39 - 216 985 - 1217 1 12182004 46 - 184 912 - 1142 12 11542005 48 - 198 887 - 1133 66 11992006 52 - 223 966 - 1241 72 13132007 83 - 119 677 - 879 133 1012

1Estimated by the Working Group.2Divisions VIId,e = 4,739 t.3Included in Division VIId


5.4.10 Plaice southwest of Ireland (Division VIIh–k)

Single-stock exploitation boundaries The new data available for this stock do not change the perception of the stock and do not give reason to change the advice from 2007. The advice on this stock for the fishery in 2009 is therefore the same as the advice given in 2007 for the 2008 fishery: “Catches should be no more than the recent average (2004–2006) of around 177 t, in order to avoid an expansion of the fishery until there is more information to facilitate an adequate assessment”. Source of information Report of the Working Group on the Assessment of Southern Shelf Demersal Stocks, 30 April–6 May 2008 (ICES CM 2008/ACOM:12). Year ICES

Advice

Single-stock exploitation boundaries


Predicted catch


stock boundaries

Agreed TAC

ICES landings

1993 - - - 655 1994 - - - 577 1995 - - - 542 1996 - - - 453 1997 - - - 645 1998 - - - 444 1999 - - - 406 2000 - - - 299 2001 - - 1215 261 2002 - - 1080 313 2003 Reduce TAC

to recent average (1998–2000)

450 582 217

2004 1 Reduce TAC to recent average (2000–2002)

1 320 466 221

2005 Reduce TAC to recent average (2001–2003)

271 466 164


245 396 147


196 337 120


177 303

2009 Same advice as last year 177

Weights in t. 1 Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits.


Table 5.4.10.1 Plaice in Divisions VII h–k (Southwest Ireland). Nominal landings (t), 1987–2006, as officially reported to ICES.

Country 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 Belgium* 250 245 403 301 252 246 344 197 235 304 442 Denmark 1 1 1 - - - - - - - - France 85 135 229 77 173 90 64 48 60 48 69 Ireland 300 369 454 338 478 477 383 271 321 305 344 Netherlands - - - - - - - - - 52 - Spain - - - - - - - - - - - UK – E W NI . . 73 88 287 264 218 258 282 154 138 UK – E W 246 433 . . . . . . . . . UK - Scotland - 1 - 1 1 6 7 1 4 1 1 USSR - - - - - . . . . . . Total 882 1184 1160 805 1191 1083 1016 775 902 864 994 Unallocated -361 -198 -360 -411 -349 WG estimate 655 577 542 453 645 Country 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 Belgium 335 45 4 27 69 20 67 32 22 7 Denmark - - - - - - - France 49 . 54 50 45 33 34 22 37 14 Ireland 286 299 200 160 155 127 91 90 65 71 Netherlands 13 1 2 - - - - . Spain - 1 5 3 2 6 6 . 1 UK – E W NI 106 82 75 73 59 56 36 28 18 20 UK – E W . . . . . . . . UK - Scotland 1 1 1 - - - - . USSR . . . . . . . . Total 790 428 341 313 330 242 234 172 143 112 Unallocated -346 -22 -42 -52 -17 -25 -13 -8 4 8 WG estimate 444 406 299 261 313 217 221 164 147 120

* Belgian landings highlighted include VIIg.


5.4.11 Plaice west of Ireland (Divisions VIIb,c)

Single-stock exploitation boundaries The new data available for this stock do not change the perception of the stock and do not give reason to change the advice from 2007. The advice on this stock for the fishery in 2009 is therefore the same as the advice given in 2007 for the 2008 fishery: “Catches should be no more than the recent average (2004–2006) of around 40 t, in order to avoid an expansion of the fishery until there is more information to facilitate an adequate assessment”. Source of information Report of the Working Group on the Assessment of Southern Shelf Demersal Stocks, 30 April–6 June 2008 (ICES CM 2008/ACOM:12). Year ICES

Advice



Predicted catch


stock boundaries

Agreed TAC

ICES landings

1993 - - - 197 1994 - - - 215 1995 - - - 315 1996 - - - 240 1997 - - - 213 1998 - - - 183 1999 - - - 172 2000 - - - 108 2001 - - 240 87 2002 No advice - 180 71 2003 Reduce TAC

to recent landings

160 160 72

2004 1 Reduce TAC to recent av. landings (2000–2002)

1 90 160 55

2005 Reduce TAC to recent av. landings (2001–2003)

77 160 38


65 144 30


55 122 34


40 110

2009 Same advice as last year 40



Table 5.4.11.1 Plaice in Divisions VII b, c (Southwest Ireland). Nominal landings (t) 1973–2006 as officially reported to ICES.

COUNTRY 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983

Denmark - - - - - - 2 - - - - France 60 45 10 9 4 16 6 12 9 8.00 37 Ireland 124 106 153 133 135 122 117 142 135 122 108 Spain - - - - - - - 65 58 22 7 UK - E W NI . . . . . . . . . . . UK - E W 1 1 - - - - - - 4 4 - UK - Scotland - - - - - - - - - - - Total 185 152 163 142 139 138 125 219 206 156 152

COUNTRY 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 Denmark - - - - - - - - - - - - France 2 10 11 13 9 1 11 9 3 2 1 5 Ireland 110 150 114 153 157 159 130 179 180 191 200 239 Spain - - - - - - - - - - - - UK - E W NI . . . . . 1 2 - 6 1 2 1 UK - E W 3 7 5 1 2 . . . . . . . UK - Scotland 3 - - - - 13 90 3 3 2 3 1 Total 118 167 130 167 168 174 233 191 192 196 206 246

COUNTRY 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 Denmark - - - - - - - - - . France 1 3 - . 31 8 17 8 16 14 11 10 Ireland 248 206 160 157 99 70 51 56 39 25 20 23 Spain - - - - - - - 2 1 . 1 UK - E W NI 2 - 1 - - - 2 - - . UK - E W . . . . . . . . . . UK - Scotland - - - 2 - - - - - . UK 0 Total 251 209 161 159 130 78 70 66 56 39 32 33 Unallocated -11 4 22 13 -22 9 1 6 -1 -1 -2 1 WG Estimate 240 213 183 172 108 87 71 72 55 38 30 34


5.4.12 Sole in Division VIIa (Irish Sea)





Comment


At risk of being harvested unsustainably


Based on the most recent estimates of SSB (in 2008) fishing mortality (in 2007) ICES classifies the stock as suffering reduced reproductive capacity and at risk of being harvested unsustainably. SSB has declined since 2001 to low levels and reached the lowest level in 2007. Fishing mortality has been close to or above Flim throughout most of the time-series. Recent recruitment levels have been lower than earlier in the time-series. Management objectives There are no explicit management objectives for this stock. Reference points Type Value Technical basis

Blim 2200 t Blim = Bloss The lowest observed spawning stock, followed by an increase in SSB.

Bpa 3100 t Bpa ~ Blim * 1.4. The minimum SSB required ensuring a high probability of maintaining SSB above its lowest observed value, taking into account the uncertainty of assessments.

Flim 0.40 Flim = Floss. Although poorly defined, there is evidence that fishing mortality in excess of 0.4 has led to a general stock decline and is only sustainable during periods of above-average recruitment.


Fpa 0.30 This F is considered to have a high probability of avoiding Flim. Targets Fy Not defined. (changed in 2007, SSB estimates rescaled) Yield and spawning biomass per Recruit F-reference point: Fish Mort Yield/R SSB/R Ages 4–7 Average last 3 years 0.44 0.20 0.54 Fmax 0.91 0.21 0.30 F0.1 0.19 0.18 1.10 Fmed 0.27 0.19 0.83

Candidates for reference points consistent with taking high long-term yields and achieving a low risk of depleting the productive potential of the stock are in the range of F0.1-Fpa. Single-stock exploitation boundaries Exploitation boundaries in relation to high long-term yield, low risk of depletion of production potential and considering ecosystem effects Fishing mortality is estimated to be well above F0.1 (0.19).


Exploitation boundaries in relation to precautionary limits Given the low SSB and low recruitment since 2000, it is not possible to identify any non-zero catch which would be compatible with the precautionary approach. ICES recommends a closure of the fishery in 2009 and a recovery plan should be developed and implemented as a prerequisite to reopening the fishery. Short-term implications Outlook for 2009 Basis: F(2008) = Fsq = mean F(05–07) = 0.44; R08 = RCT3 = 3.7 million; R09–10 = GM70–05 = 5.7 million; SSB(2009) = 1.85; landings (2008) = 0.60.

Rationale TAC(2009) (1) Basis F(2009) SSB(2010) %SSB

change %TAC change

Zero catch 0.00 F=0 0.00 2.85 54% -100%

Status quo 0.68 Fsq 0.44 2.22 20% 2%


0.08 Fsq *0.1 0.04 2.78 50% -88%

0.19 Fsq *0.25 0.11 2.67 45% -71%

0.37 Fsq *0.5 0.22 2.51 36% -45%

Status quo 0.49 Fsq *0.68 0.30 2.40 30% -27%

0.53 Fsq *0.75 0.33 2.36 27% -20%

0.68 Fsq *1 0.44 2.22 20% 2%

0.74 Fsq *1.1 0.49 2.17 17% 10%

0.79 Fsq *1.2 0.53 2.12 15% 18% All weights in thousand tonnes. Shaded scenarios are not considered consistent with the precautionary approach. Management considerations Given the recent low recruitment, it is not possible for the stock to reach Bpa in one year. At status quo fishing mortality, SSB is estimated to levels close to Blim in 2010. ICES recommends a recovery plan. A recovery plan should offer maximum protection to the sole, recognizing that it is caught in a mixed-fishery. A recovery plan should include monitoring the trajectory of the stock, clearly stating specified reopening criteria, and monitoring the fishery when it is reopened. Sole is caught in a mixed fishery with other flatfish as well as gadoids. Information from observer trips indicates that discarding of sole is between 0 and 8% in number. Impacts of fisheries on the ecosystems Sole is predominantly caught by beam trawl fisheries. Although discard rates of sole are low in these fisheries, discard rates of other (commercial and non-commercial) species can be considerable. Beam trawling, especially using chain-mat gear, is known to have a significant impact on the benthic communities, although less so on soft substrates and in areas which have been historically exploited by this fishing method. Factors affecting the fisheries and the stock Regulations and their effects Technical measures in force are minimum mesh sizes and minimum landing size (24 cm). The closures of cod spawning grounds that have been in force since 2000 are unlikely to have had a big impact on the sole fishery. In 2000 the closure covered the Western and Eastern Irish Sea. Since then, closure has been mainly in the western part, whereas the main sole fishery has taken place in the eastern part of the Irish Sea.


Changes in fishing technology and fishing patterns Fishing behavior has changed in response to high fuel prices. There has been a switch by Irish trawlers to reduce gear size in some cases by as much as 20%. There is also evidence of larger vessels switching from twin-rigging back to single rigging to reduce fuel consumption. The 24 m+ range vessels are now working at around 50–60% of their total power in a bid to reduce fuel costs. This implies a reduction in catch rates, and may also effect the length distribution of the catches. Around 10% of the Belgian beam trawlers were decommissioned between August 2005 and November 2006 (having its full impact from 2007 onwards). Over the period 2000–2004, these vessels accounted for on average 13.7% of the total kW days in the Irish Sea. Impacts of the environment on the fish stock There was no information available on impacts of the environment on sole in Division VIIa. Scientific basis Data and methods The assessment is based on landings-at-age data and two surveys. Some errors in the historical indices for one of the tuning fleets were corrected. This resulted in revisions of the historical estimates of fishing mortality and SSB, but did not have an impact on the general perception of the population dynamics for this stock. Uncertainties in assessment and forecast Given the low stock size, predictions become more dependent on the assumed incoming recruitment. More than 50% of the predicted SSB in 2010 is based on the assumption. Information from the fishing industry There was no information from the fishing industry available to ICES. Comparison with previous assessment and advice The estimate of SSB(2007) this year is 10% lower than last year and the estimate of F(2006) 10% higher. Neither the advice nor the basis has been changed compared to last year. Source of information Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 15–21 May 2008 (ICES CM 2008/ACOM:08).


Year ICES

Advice Single-stock exploitation boundaries4

Predicted catch

corresp. to advice

Predicted catch


stock boundaries

Agreed TAC

Official Landings

ICES Landings2

1987 No increase in F 1.9 2.1 2.0 2.8 1988 80% of F(86); TAC 1.6 1.75 1.9 2.0 1989 80% of F(87); TAC < 1.48 1.48 1.8 1.8 1990 Interim advice 1.053 1.5 1.6 1.6 1991 90% of F(89); TAC 1.3 1.5 1.2 1.2 1992 No long-term gains in

increased F 1.21 1.35 1.2 1.3

1993 F = F(91) ~ 920 t 0.92 1.0 1.0 1.0 1994 No long-term gains in

increased F 1.511 1.5 1.4 1.4

1995 20% reduction in F 0.8 1.3 1.3 1.3 1996 20% reduction in F 0.8 1.0 1.0 1.0 1997 20% reduction in F 0.8 1.0 1.0 1.0 1998 20% reduction in F 0.85 0.9 0.9 0.9 1999 Reduce F below Fpa 0.83 0.9 0.8 0.9 2000 Reduce F below Fpa < 1.08 1.08 0.8 0.8 2001 Reduce F below Fpa < 0.93 1.1 1.0 1.1 2002 Keep F below Fpa <1.10 1.1 1.0 1.1 2003 Keep F below Fpa <1.01 1.01 1.0 1.0 2004 Maintain SSB

above Bpa <0.79 0.80 0.6 0.7

2005 F<Fpa <1.00 0.96 0.77 0.8

2006 Recent catch levels (2002–

2004)

<0.93 0.96 0.57 0.57

2007 Maintain SSB above Bpa Zero catch 0 0.82 0.49 0.49

2008 Zero catch 0 0.67

2009 Zero catch and recovery plan

0

Weights in ‘000 t. 1) Catch at status quo F. 2) Not including misreporting. 3) Revised in 1990 to 1.5. 4) Single-stock boundary; the exploitation of this stock should be conducted in the context of mixed fisheries.


Figure 5.4.12.1 Sole (Solea solea) in Division VIIa. Landings, fishing mortality, recruitment, and SSB.

Landings

0

0.5

1

1.5

2

2.5

3

1970 1975 1980 1985 1990 1995 2000 2005

Land

ings

in 1

000

t

Fishing Mortality

0.00.10.20.30.40.50.60.70.80.9

1970 1975 1980 1985 1990 1995 2000 2005

F(ag

es 4

-7)

F

Flim

Fpa

Recruitment (age 2)

0

5

10

15

20

25

1970 1975 1980 1985 1990 1995 2000 2005

Rec

ruitm

ent i

n m

illio

ns


012345678

1970 1975 1980 1985 1990 1995 2000 2005

SSB

in 1

000

t

SSB

Blim

Bpa


Figure 5.4.12.2 Sole (Solea solea) in Division VIIa. Stock–recruitment, yield and SSB per recruit, precautionary

approach.

Stock - Recruitment

0

5

10

15

20

25

0 2 4 6 8

SSB in 1000 t

Rec

ruitm

ent (

age

2) in

m

illio

ns SSB-Rec.

Blim

Bpa


0

0.05

0.1

0.15

0.2

0.25

0 0.2 0.4 0.6 0.8 1


Yiel

d (d

ashe

d lin

e)

00.51

1.522.53

3.54

SSB

(lin

e)


012345678

0.0 0.2 0.4 0.6 0.8 1.0


SSB

in 1

000

t

F-SSB

2007

Flim

Fpa

Blim

Bpa


Sole in Division VIIa (Irish Sea)

0

1

2

3

4

5

6

7

8

1990 1995 2000 2005

SSB ('000 tonnes)

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

1990 1995 2000 2005


0

2

4

6

8

10

12

14

16

1990 1995 2000 2005


Figure 5.4.12.3 Sole in Division VIIa. Comparison of current assessment with previous assessments.

ICES

Adv

ice

2008

, Boo

k 5

104

Tab

le 5

.4.1

2.1

Sole

in D

ivis

ion

VII

a (I

rish

Sea)

. Nom

inal

land

ings

(ton

nes)

as o

ffia

lly re

porte

d to

ICES

, and

wor

king

gro

up e

stim

ates

of t

he la

ndin

gs.

Cou

ntry

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

*20

07*

Bel

gium

930

987

915

1010

786

371

531

495

706

675

533

570

525

469

493

674

817

687

527

662

419.

330

6.3

Fran

ce17

511

52

311

87

55

33

0.5

34

44

13

0.4

2.1

Irela

nd23

531

236

615

517

019

816

498

226

176

133

130

134

120

135

135

9610

377

8582

.510

9.3

Net

herla

nds

--

--

--

--

--

149

123

6046

60-

--

--

--

UK

(Eng

l.& W

ales

)163

759

950

761

356

958

147

733

840

942

419

418

916

116

513

319

516

521

710

610

369

.469

.4

UK

(Isl

e of

Man

)1

31

210

4414

45

124

53

11

++

++

++

n/a

UK

(N. I

rela

nd)1

5072

47

UK

(Sco

tland

)46

6338

3839

2637

2814

85

79

88

43

31

1n/

an/

a

Tota

l19

1620

4118

8518

2315

7612

2312

3497

113

6713

0049

010

2789

581

083

310

1210

8510

1471

285

457

248

7

Use

d by

WG

1995

2808

1999

1833

1583

1212

1259

1023

1374

1266

1002

1003

911

863

818

1053

1087

1014

699

855

569

492

Una

lloca

ted

7976

711

410

7-1

125

527

-34

512

-24

1654

-15

412

0-1

31

-35

* P

relim

inar

y

1 198

9 on

war

ds:

N. I

rela

nd in

clud

ed w

ith E

ngla

nd &

Wal

es



Table 5.4.12.2 Sole in Division VIIa (Irish Sea).


1970 3695 6071 1785 0.390 1971 10179 5895 1882 0.440 1972 3186 4653 1450 0.451 1973 13138 4830 1428 0.430 1974 5873 4706 1307 0.444 1975 6684 4961 1441 0.395 1976 3859 4506 1463 0.427 1977 15792 3943 1147 0.369 1978 9061 4492 1106 0.357 1979 8891 5229 1614 0.474 1980 5098 5199 1941 0.635 1981 4542 4899 1667 0.479 1982 2508 3964 1338 0.437 1983 5710 3931 1169 0.430 1984 15623 4398 1058 0.345 1985 16289 5208 1146 0.326 1986 23802 6333 1995 0.420 1987 3445 6678 2808 0.798 1988 3547 5173 1999 0.589 1989 4395 4321 1833 0.558 1990 5590 3376 1583 0.646 1991 12630 2939 1212 0.498 1992 4855 3179 1259 0.526 1993 6190 2901 1023 0.523 1994 5328 3797 1374 0.488 1995 2017 3208 1266 0.512 1996 2529 2510 1002 0.538 1997 8171 2242 1003 0.625 1998 6841 2857 911 0.481 1999 5978 3148 863 0.453 2000 6003 2806 818 0.556 2001 3950 3718 1053 0.325 2002 2786 3539 1090 0.409 2003 3108 3178 1014 0.366 2004 3391 2492 709 0.280 2005 3327 2147 855 0.536 2006 1776 1742 569 0.472 20071 2390 1594 492 0.315 2008² 3746 1620

Average 6562 3907 1307 0.467 1 RCT3 estimate. 2 GM recruitment.


5.4.13 Sole in Divisions VIIf,g (Celtic Sea)





Comment



Overfished No agreed target

Based on the most recent estimates of SSB and fishing mortality, ICES classifies the stock as having full reproductive capacity and being harvested sustainably. SSB in 2008 is estimated to be above Bpa. Fishing mortality in 2007 is estimated to be below Fpa. Management objectives There are no specific management objectives for this stock. Reference points Type Value Technical basis

Blim not defined. Bpa 2 200 t There is no evidence of reduced recruitment at the lowest biomass

observed and Bpa can therefore be set equal to the lowest observed SSB.

Flim 0.52 Flim: Floss. Precautionary approach

Fpa 0.37 This F is considered to have a high probability of avoiding Flim and maintaining SSB above Bpa in 10 years, taking into account the uncertainty of assessments. Fpa: Flim × 0.72; implies a less than 5% probability that (SSBMT< Bpa).

Targets Fy not defined. (unchanged since: 1998)

Yield and spawning biomass per Recruit F-reference points: Fish Mort Yield/R SSB/R Ages 4–8 Average last 3 years 0.31 0.18 0.58 Fmax 0.25 0.19 0.73 F0.1 0.12 0.17 1.49 Fmed 0.27 0.19 0.68

A candidate for a target reference point consistent with taking high long-term yields and achieving a low risk of depleting the productive potential of the stock may be identified in the range of F0.1 (0.12) and Fmax (0.25). Single-stock exploitation boundaries Exploitation boundaries in relation to high long-term yield, low risk of depletion of production potential and considering ecosystem effects The current fishing mortality (2007) is estimated to be 0.33, which is above the rate expected to lead to high long-term yields and low risk of stock depletion. Exploitation boundaries in relation to precautionary limits F should be kept below Fpa, corresponding to landings of less than 1090 tonnes in 2009. This is expected to keep the stock above Bpa.


Conclusion on exploitation boundaries In the present situation with a stock that is above Bpa and a fishing mortality below Fpa, there is no long-term gain in yield to increase fishing mortality. ICES therefore recommends to limit landings in 2009 to no more than 940 t. Outlook for 2009 Basis: F(2008) = Fsq = mean F(05–07) = 0.31; R08–10 = GM71–05 = 5.0 million; SSB(2008) = 3.3; SSB(2009) = 3.05; landings (2008) = 0.97.

Rationale TAC(2009) (1) Basis F(2009) SSB(2010) %SSB

change %TAC change

Zero catch 0.00 F=0 0.00 3.93 29% -100%


0.11 Fsq *0.1 0.03 3.82 25% -89%

0.26 Fsq *0.25 0.08 3.66 20% -73%

0.50 Fsq *0.5 0.16 3.42 0.12 -0.48

Status quo 0.73 Fsq *0.75 0.23 3.19 4% -24%

0.86 Fsq *0.9 0.28 3.06 0% -11%

0.94 Fsq *1 0.31 2.98 -3% -3%

1.02 Fsq *1.1 0.34 2.90 -5% 5% Precautionary

approach 1.09 Fpa = Fsq *1.2 0.37 2.82 -8% 13%

All weights in thousand tonnes. Shaded scenarios are not considered consistent with the precautionary approach. (1) It is assumed that the TAC will be implemented and that the landings in 2009 therefore correspond to the TAC. Management considerations Sole is mainly taken in a beam trawl fishery as part of a mixed demersal fishery with plaice and, to a lesser extent, cod. Both of the latter stocks require a reduction in fishing mortality. The Celtic Sea is an area without days-at-sea limitations for demersal fisheries. In the past this has resulted in increased effort in the Celtic Sea as a direct result of restrictive effort in other areas. This was particularly the case in 2004–2005 when effort in the sole fishery increased because of restrictive days at sea in the eastern channel (Division VIId).

Effects on fisheries in the ecosystem Sole is predominantly caught by beam trawl fisheries. Although discard rates of sole are low in these fisheries, discard rates of other (commercial and non-commercial) species can be considerable. Beam trawling, especially using chain-mat gear, is know to have a significant impact on the benthic communities, although less so on soft substrates and in areas which have been historically exploited by this fishing method. Beam trawlers are using benthic drop-out panels that release about 75% of benthic invertebrates from the catches. Full square mesh codends are also being tested in order to reduce the capture of benthos further and improve the selection profile on gadoids. Factors affecting the fisheries and the stock The fisheries for sole in the Celtic Sea and Bristol Channel involve vessels from Belgium taking two thirds, the UK one quarter, and France and Ireland taking minimal amounts of the total landings. The sole fishery is concentrated on the northern Cornish coast off Trevose Head and around Lands End. Sole are taken mainly in a beam trawl fishery that started in the early 1960s and, to a lesser extent, in the longer established otter trawl fisheries. In the 1970s, the fishery was mainly carried out by Belgian beam trawlers and Belgian and UK otter trawlers. The use of beam trawls (to target sole and plaice) increased during the mid-1970s, and the Belgian otter trawlers have now been almost entirely replaced by beam trawlers. Effort in the Belgium beam trawl fleet increased in the late 1980s as vessels normally operating in the North Sea were attracted to the west by improved


fishing opportunities. Beam trawling by UK vessels increased substantially from 1986, reaching a peak in 1990 and decreasing thereafter. In the Celtic Sea, the beam and otter trawl fleets also take other demersal species such as plaice, cod, rays, brill, turbot, and anglerfish. Effects of the environment The main spawning areas for sole in the Celtic Sea are in waters 40 to 75 m deep, off Trevose Head, and spawning usually takes place between February and April. Juvenile sole are found in relatively high abundance in depths up to 40 m, and adult sole (fish aged 3 plus) are generally found in deeper water. Spawning and nursery grounds are well defined. The results of recent tagging experiments suggest that there is only limited movement of sole between the Bristol Channel (Division VIIf) and adjacent areas (Division VIIg). Regulations and their effects Since 2005, ICES rectangles 30E4, 31E4, and 32E3 have been closed during the first quarter (Council Regulations 27/2005, 51/2006, 41/2007 and 40/2008) with the intention of reducing fishing mortality on cod. The effects of the closure on sole are not known although there have been spatial and temporal changes in the distribution of effort. Changes in fishing technology and fishing patterns Beam trawlers account for the majority of the vessels targeting sole. Recent increases in fuel costs are thought to have restricted the range of some fleets and may have resulted in a reduction in effort in Division VIIfg. In addition, several vessels of this fleet segment are developing methods to reduce fuel costs.

A decommissioning scheme reduced the capacity in the UK SW beam trawl fleet in 2007. Nine Belgian beam trawlers were decommissioned between August 2005 and November 2006. Over the period 2000–04, these vessels accounted for an average 17.6% of the total kW-days in the Celtic Sea. Scientific basis Data and methods The analytical age-based assessment is based on landings, two commercial cpue series, and one survey index. Information from the fishing industry The perception of the status of Celtic Sea sole by the UK fishing industry was in line with the assessment for this stock. No additional information was received from the Belgian, French, and Irish industries. Uncertainties in assessment and forecast The catch numbers appear to be reasonably reliable. In the 2007 data, there were conflicting signals between the commercial cpue series (with a strong increase of the catch rates) and the survey indices (with similar catch rates as in previous years). Comparison with previous assessment and advice The general trends in the estimates of the stock numbers, fishing mortality, and recruitment are similar to those of the previous assessment. In this assessment SSB and fishing mortality have been revised over several years. There has been an upward revision of SSB by 10% in 2007, and a downward revision of fishing mortality by 20%. The advice last year was based on Fpa. This advice this year is based on no increase in F because there is no long-term gain in increasing fishing mortality. Source of information Report of the Working Group on the Assessment of Southern Shelf Demersal Stocks, 30 April–6 May 2008 (ICES CM 2008/ACOM:12).


Year ICES Advice



Predicted catch corresponding to single-stock boundaries

AgreedTAC

ICES Landings

1987 Status quo F; TAC 1.6 1.6 1.22 1988 F = F(pre-86); TAC 0.9 1.1 1.15 1989 F at F(81–85); TAC 1.0 1.0 0.99 1990 No increase in F 1.2 1.2 1.19 1991 No increase in F 1.1 1.2 1.11 1992 No long-term gains

i i i 1.1 1.2 0.98

1993 No long-term gains i i i

- 1.1 0.93 1994 No long-term gains

i i i - 1.1 1.01

1995 No increase in F 1.0 1.1 1.16 1996 20% reduction in F 0.8 1.0 1.00 1997 20% reduction in F 0.8 0.9 0.93 1998 20% reduction in F 0.7 0.85 0.88 1999 Reduce F below Fpa 0.81 0.96 1.01 2000 Reduce F below Fpa <1.16 1.16 1.09 2001 Reduce F below Fpa < 0.81 1.02 1.17 2002 Reduce F below Fpa < 1.00 1.07 1.35 2003 Reduce F below Fpa < 1.24 1.24 1.39 2004 1 Reduce F below Fpa 1 < 1.00 1.05 1.25

2005 1 Reduce F below Fpa 1 < 0.84 1.00 1.04



2008 1 Keep F below Fpa 1 < 1.00 0.96

2009 1 No long-term gain in increasing F

1 < 0.94

Weights in ‘000 t. 1 Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits.


Figure 5.4.13.1 Sole in Divisions VIIf and g (Celtic Sea). Landings, fishing mortality, recruitment, and SSB.

Landings

0

0.5

1

1.5

2

1971 1976 1981 1986 1991 1996 2001 2006

Land

ings

in 1

000

t

Fishing Mortality

0.00.1

0.20.30.40.5

0.60.7

1971 1976 1981 1986 1991 1996 2001 2006

F(ag

es 4

-8)

F

Flim

Fpa

Recruitment (age 1)

02468

10121416

1971 1976 1981 1986 1991 1996 2001 2006

Rec

ruitm

ent i

n m

illio

ns


0123456789

1971 1976 1981 1986 1991 1996 2001 2006

SSB

in 1

000

t

SSB

Bpa


Figure 5.4.13.2 Sole in Divisions VIIf and g (Celtic Sea). Stock and recruitment, yield, and SSB per recruit.

Stock - Recruitment

024

68

1012

1416

0 2 4 6 8 10

SSB in 1000 t

Rec

ruitm

ent (

age

1) in

m

illio

ns SSB-Rec.

Bpa


00.020.040.060.080.1

0.120.140.160.180.2

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7


Yiel

d (d

ashe

d lin

e)

00.511.522.533.544.5

SSB

(lin

e)


0123456789

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7


SSB

in 1

000

t

F-SSB

2007

Flim

Fpa

Bpa


Figure 5.4.13.2 Sole in Divisions VIIf and g (Celtic Sea). Comparison of current assessment with previous assessments.

Sole in Divisions VIIf and g (Celtic Sea)

0

1

1

2

2

3

3

4

4

5

1990 1995 2000 2005

SSB ('000 tonnes)

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

1990 1995 2000 2005


0

2

4

6

8

10

12

14

16

1990 1995 2000 2005


ICES

Adv

ice

2008

, Boo

k 5

113

Tab

le 5

.4.1

3.1

Cel

tic S

ea so

le. D

ivis

ions

VII

f and

VII

g. O

ffic

ial N

omin

al la

ndin

gs (t

), 19

86–2

007

and

data

use

d by

the

Wor

king

Gro

up.

C

ount

ry19

8619

8719

8819

8919

9019

9119

9219

9319

9419

9519

9619

9719

9819

9920

0020

0120

0220

0320

0420

0520

061

2007

1

Bel

gium

1039

*70

1*

705

*68

4*

716

*98

2*

543

*57

5*

619

*76

3*

695

*66

0*

675

*60

469

472

070

371

573

564

857

858

1.8

Den

mar

k2

--

--

--

--

--

--

--

--

--

--

-

Fran

ce14

611

711

087

130

8014

110

890

8810

299

9861

7477

6512

479

104

4867

.67

Irela

nd18

8*

972

1840

3245

5137

2019

2842

5129

3532

2633

3436

31.9

UK

(E. &

W,N

I.)61

1*

437

317

203

353

402

325

285

264

294

265

251

198

231

243

288

318

342

283

217

232

244.

3

UK

(Sco

tland

)-

--

-0

06

118

-0

0-

0-

-+

+-

--

-

Net

herla

nds

3-

--

--

--

--

--

--

--

--

--

--

Tota

l19

8912

6412

0499

212

3914

9610

6010

3010

1811

6510

8110

3810

1394

710

4011

2011

1812

0711

3010

0389

492

6

Use

d by

WG

1600

1222

1146

992

1189

1107

981

928

1009

1157

995

927

875

1012

1091

1168

1345

1392

1249

1044

946

938

Una

lloca

ted

-389

-42

-58

0-5

0-3

89-7

9-1

02-9

-8-8

6-1

11-1

3865

5148

227

185

119

4152

12

1 Pre

limin

ary

* In

clud

ing

VIIg

-k



Table 5.4.13.2 Sole in Divisions VIIf and g (Celtic Sea).

Year Recruitment SSB Landings Mean F Age 1 Ages 4-8 thousands tonnes tonnes

1971 9580 7971 1861 0.364 1972 4264 6285 1278 0.267 1973 3378 5256 1391 0.232 1974 3394 5626 1105 0.234 1975 2967 4986 919 0.199 1976 5187 4324 1350 0.364 1977 4629 4636 961 0.246 1978 5486 3732 780 0.186 1979 3530 3857 954 0.266 1980 5126 3996 1314 0.293 1981 4855 3401 1212 0.346 1982 4885 3536 1128 0.334 1983 6782 3638 1373 0.440 1984 4698 3894 1266 0.398 1985 5644 3292 1328 0.424 1986 3151 3352 1600 0.527 1987 5730 2506 1222 0.554 1988 4482 2692 1146 0.540 1989 3714 2097 992 0.515 1990 8597 2388 1189 0.636 1991 4197 2108 1107 0.464 1992 4452 2426 981 0.391 1993 4423 2459 928 0.443 1994 3406 2238 1009 0.511 1995 3316 2138 1157 0.639 1996 4040 2063 995 0.566 1997 5460 1807 927 0.664 1998 6268 1611 875 0.662 1999 15073 1809 1012 0.562 2000 7636 1925 1091 0.356 2001 3988 3092 1168 0.425 2002 6594 4044 1345 0.442 2003 5380 3683 1392 0.547 2004 5792 3401 1249 0.380 2005 5512 3384 1044 0.334 2006 2893 2964 946 0.263 2007 5072 3177 938 0.328 2008 4975* 3272

Average 5225 3396 1150 0.415 * GM71–05.


5.4.14 Sole in Division VIIe (Western Channel)





Comment

Increased risk Harvested unsustainably

Overfished Above target

ICES classifies the stock as being at risk of reduced reproductive capacity and being harvested unsustainably. SSB has declined since 1980 and is estimated at a historic low in 2006–07. Fishing mortality has been above Fpa since 1979, and mostly above Flim since 1982. Fishing mortality has generally increased since the mid-1990s. Management objectives Council Regulation (EC) No. 509/2007 establishes a multi-annual plan for the sustainable exploitation of Division VIIe sole (see 5.4.14 Annex). Years 2007–2009 are deemed a recovery plan, with subsequent years being deemed a management plan. For 2007, 2008, and 2009 the TAC shall be set at the highest value resulting from either a 20% reduction in F compared to Fbar (03–05) or an F of 0.27, with a maximum TAC variation of no more than 15%. The EC management plan has not been evaluated by ICES. ICES cannot conclude whether this management plan is in accordance with the precautionary approach. ICES will endeavour to carry out an evaluation of the agreed management plan over the summer of 2008 and will report on results of such an evaluation in September 2008. However, in 2005 ICES explored simulations with long-term target Fs from 0.1 to 0.3 that are predicted to result in the highest long-term yields, whilst posing little risk of being below Blim in the long term. The agreed F target is within this range, but is above Fpa. Reference points Type Value Technical basis

Blim 2 000 t Blim = Bloss, the lowest observed spawning-stock biomass. Bpa 2 800 t Historical development: Biomass below this has increased risk of

reduced recruitment. Flim 0.28 Flim = Floss. The fishing mortality estimated to lead to potential stock

collapse.


Fpa 0.20 Fpa:Flim*0.72 Targets Fy 0.27 Multi-annual plan. (unchanged since: 2001, target point added 2007) Yield and spawning biomass per Recruit F-reference points:


Fishing mortality around F = 0.27 (as in the management plan) can be considered as a candidate target reference point. Single-stock exploitation boundaries Exploitation boundaries in relation to existing management plans The multi-annual plan implies a 20% reduction in F compared to average F(03–05), corresponding to landings of 650 t. This is a 15% reduction in the TAC compared to 2008.


Exploitation boundaries in relation to high long-term yield, low risk of depletion of production potential and considering ecosystem effects Fishing mortality around F = 0.27 can be considered as a candidate target reference point consistent with taking high long-term yields and achieving a low risk (< 5%) of depleting the productive potential. The present fishing mortality (0.42) is above the candidate reference point. Exploitation boundaries in relation to precautionary limits Rebuilding the stock above Bpa in just one year would require that fishing mortality is reduced by 70%. This would correspond to landings of around 320 tonnes in 2009. Conclusion on exploitation boundaries Considering that the management plan has not been evaluated by ICES, ICES advises on the basis of precautionary limits. This corresponds to a TAC of less than 320 t in 2009. Short-term implications Outlook for 2009 Basis: F(2008) = Fsq = mean F(05–07) = 0.42; R07–09 = GM = 4.4 million; SSB(2009) = 2.26; landings (2008) = 0.96.

Rationale TAC(2009) Basis F(2009) SSB(2010) %SSB

change 1) %TAC

change 2)

Zero catch 0.00 F=0 0.00 3.11 38% -100%

Status quo 0.93 Fsq 0.42 2.21 -2% 22%

Management Plan 0.65 F(m-plan) 0.28 2.48 10% -15%


0.05 Fpa * 0.1 0.02 3.05 35% -93% 0.13 Fpa * 0.25 0.05 2.98 32% -83%

0.25 Fpa * 0.5 0.10 2.86 27% -67% 0.32 Fpa * 0.6 0.12 2.80 24% -58% 0.37 Fpa * 0.75 0.15 2.74 21% -52%

0.44 Fpa * 0.90 0.18 2.68 19% -42%

0.49 Fpa 0.20 2.64 17% -36%

0.53 Fpa * 1.1 0.22 2.59 15% -31%

Precautionary limits

0.60 Fpa * 1.25 0.25 2.53 12% -22% Weights in ‘000 t. Shaded scenarios are not considered consistent with the precautionary approach. 1 SSB 2010 relative to SSB 2009. 2 TAC 2009 relative to TAC 2008. Management considerations Sole are widespread and usually taken in conjunction with other species to varying degrees, dependent on location and season. The most productive sole fishery grounds are located close to ports, while the highest catches of anglerfish for example are taken further south and west in Division VIIe. Therefore, effort restrictions and/or high fuel costs will have a tendency to increase F in sole and reduce F in anglerfish. Area misreported landings between Divisions VIId and VIIe have been a problem in the past, but has been greatly reduced in recent years. The principal gears used for this stock are beam trawls, otter trawl, and nets. Sole tends to be the target species of an offshore beam trawl fleet, which is concentrated off the south Cornish and Devon coast. This fishery also takes substantial catches of plaice, anglerfish, lemon sole, and cuttlefish as part of a diverse mixed fishery. French otter trawlers and netters take sole mainly as a bycatch fishery, and also as a targeted fishery at spawning time.


In recent years, UK vessels, mainly beam trawlers, have accounted for around 60% of the total landings, while France has taken approximately a third and Belgian vessels most of the remainder. Management plan evaluations The EC management plan has not been evaluated by ICES. ICES cannot conclude whether this management plan is in accordance with the precautionary approach. ICES will endeavour to carry out an evaluation of the agreed management plan over the summer of 2008 and will report on results of such an evaluation in September 2008. However, in 2005 ICES explored simulations with long-term target Fs from 0.1 to 0.3 that are predicted to result in the highest long-term yields, whilst posing little risk of being below Blim in the long term. The agreed F target is within this range, but is above Fpa. Ecosystem considerations Beam trawling, especially using chain-mat gear, is know to have a significant impact on the benthic communities, although less so on soft substrates and in areas which have been historically exploited by this fishing method. Discard rates of non-commercial species and commercial species of unmarketable size are substantial. Factors affecting the fisheries and the stock Regulations and their effects Management of this stock is mainly by TAC, which has largely been ineffective at regulating the fishery. In 2005 effort restrictions were implemented for towed gears in this fishery in order to enforce the TAC and improve data quality. To date these restrictions have not been limiting in this fishery, in part due to the large numbers of days available, but also because in the UK fleet there appears to be a considerable amount of latent effort in the beam trawl fleet. Technical measures applied to this stock include a minimum landing size (24 cm) and minimum mesh size of 80 mm for beam trawlers. Local regulations restricting certain gear and vessel types are also in place. Changes in fishing technology and fishing patterns Recent rises in fuel cost will have impacted fishing operations in the main fleets exploiting sole; however, no quantitative evaluation of the effect is possible. The effects of decommissioning in the UK beam trawl fleet in 2007 cannot yet be evaluated. The environment There have been no demonstrated effects of environmental change for this stock. In the Western Channel the peak spawning period of sole is April and May. The main spawning areas are to the west of the Isle of Wight and in the vicinity of Hurd Deep. The nurseries are in estuaries, tidal inlets, and shallow, sandy bays. Adult sole in the Western Channel may recruit from local nurseries as well as from those in the Eastern Channel, but there is no evidence of subsequent emigration from the Western Channel. Coupled with the localized spawning areas in the Western Channel, this suggests that adult sole in the Western Channel are largely isolated from those found in northern Biscay, the eastern Celtic Sea, and the Eastern Channel. Scientific basis Data and methods The assessment is analytical, based on landings, one survey index, and four commercial cpue series. Substantial area misreporting of catches has been evident for a number of years and the catch statistics have been partially corrected for this. Estimates of unreported landings are not available and are not included in the assessment. Information from the fishing industry The industry has been cooperative in a number of scientific endeavours with regards to this stock: The fisheries science partnership, conducted cooperatively between CEFAS and the UK industry has provided evidence for the wide dispersal and wide-ranging age distribution for this stock. The age compositions of catches were similar to the ICES forecast, suggesting that survey cpue can be seen as proportional to the catch rates of the fishery. The trends in


SSB throughout the time-series are similar to the recent trends given in ICES data, and there has been a constant distribution pattern. However, this information needs a longer time series before the information can be included. Uncertainties in assessment and forecast The extent of underreporting is unknown and the current stock assessment and forecast will be conditional on the accuracy of the landings statistics. There is a bias in the assessment overestimating F and underestimating SSB in recent years. Revisions in final year estimates of F and F estimates in the reference period make the short-term forecast uncertain. Because of the uncertainty of the estimate of the incoming year-class abundance, the catch projections are based on an average recruitment for the years 1969–2004. The assumed recruitment accounts for 25% of the predicted landings in 2009 and for 39% of the predicted SSB in 2010. Comparison with previous assessment and advice The trends in the assessment are consistent with those observed previously. SSB in 2007 has been revised upwards by the most recent assessment by 7%, and fishing mortality has been revised downwards by 2%. The advice is unchanged from last year. Source of information Report of the Working Group on the Assessment of Southern Shelf Demersal Stocks, 30 April–6 May 2008 (ICES CM 2008/ACOM:12).


Year ICES Advice


Predicted catch

corresp. to advice

Predicted catch corresponding to single-stock

boundaries

Agreed TAC

Official Landings

ICES Landings

1

1987 No increase in F 1.15 1.15 1.11 1.28 1988 No decrease in SSB; TAC 1.3 1.3 0.95 1.44

1989 No decrease in SSB; TAC 1.0 1.0 0.80 1.39

1990 SSB = 3000 t; TAC 0.9 0.9 0.75 1.31 1991 TAC 0.54 0.8 0.84 0.85 1992 70% of F(90) 0.77 0.8 0.77 0.89 1993 35% reduction in F 0.7 0.9 0.79 0.90 1994 No increase in F 1.0 1.0 0.84 0.80 1995 No increase in F 0.86 0.95 0.88 0.86 1996 F96 < F94 0.68 0.70 0.74 0.83 1997 No increase in F 0.69 0.75 0.86 0.95 1998 No increase in F 0.67 0.67 0.77 0.88 1999 Reduce F below Fpa 0.67 0.70 0.66 0.96

2000 Reduce F below Fpa < 0.64 0.64 0.66 1.02


2002 Reduce F below Fpa <0.45 0.53 0.54 1.11 2003 Rebuilding plan or F=0 - 0.39 0.62 1.08 2004 F=0 or recovery plan 1 0 0.30 0.49 1.08 2005 80% reduction in F or

recovery plan <0.23 0.865 0.96 1.04

2006 80% reduction in F or recovery plan

<0.24 0.94 0.97 1.03

2007 68% reduction in F or recovery plan

<0.35 0.90 0.82 0.97

2008 75% reduction in F <0.26 0.765

2009 70% reduction in F 0.32

Weights in ‘000 t. 1 Includes misallocated landings, i.e. moving landings between two areas – not underreporting.


Figure 5.4.14.1 Sole in Division VIIe (Western Channel). Landings, fishing mortality, recruitment, and SSB.

Landings

00.20.40.60.8

11.21.41.6

1969 1974 1979 1984 1989 1994 1999 2004

Land

ings

in 1

000

t

Fishing Mortality

0.00

0.10

0.20

0.30

0.40

0.50

1969 1974 1979 1984 1989 1994 1999 2004

F(ag

es 3

-7) F

Flim

Fpa

Recruitment (age 1)

0

2

4

6

8

10

1969 1974 1979 1984 1989 1994 1999 2004

Rec

ruitm

ent i

n m

illio

ns


0

1

2

3

4

5

6

1969 1974 1979 1984 1989 1994 1999 2004

SSB

in 1

000

t

SSB

Blim

Bpa


Figure 5.4.14.2 Sole in Division VIIe (Western Channel).Stock and recruitment; yield, and SSB per recruit.

Stock - Recruitment

0123456789

10

0 1 2 3 4 5 6

SSB in 1000 t

Rec

ruitm

ent (

age

1) in

m

illio

ns SSB-Rec.

Blim

Bpa


0

0.05

0.1

0.15

0.2

0.25

0 0.2 0.4 0.6 0.8 1


Yiel

d (d

ashe

d lin

e)

00.511.522.533.544.5

SSB

(lin

e)


0

1

2

3

4

5

6

0.0 0.1 0.2 0.3 0.4 0.5


SSB

in 1

000

t

F-SSB

2007

Flim

Fpa

Blim

Bpa


Sole in Division VIIe (Western Channel)

0

1

2

3

4

5

6

1990 1995 2000 2005

SSB ('000 tonnes)

0.00

0.10

0.20

0.30

0.40

0.50

0.60

1990 1995 2000 2005


0

1

2

3

4

5

6

7

8

9

1990 1995 2000 2005


Figure 5.4.14.3 Sole in Division VIIe (Western Channel). Comparison of current assessment with previous

assessments.


Table 5.4.14.1 Sole in Division VIIe (Western Channel). Nominal landings (t) as used by the WG.


Table 5.4.14.2 Sole in Division VIIe (Western Channel).


1969 1634 2791 353 0.137 1970 3954 3066 391 0.138 1971 2987 2811 432 0.161 1972 2646 2786 437 0.122 1973 3645 3386 459 0.162 1974 3399 3275 427 0.141 1975 3174 4209 491 0.134 1976 7229 4359 616 0.164 1977 5072 4407 606 0.148 1978 4694 4981 861 0.191 1979 5165 5413 1181 0.235 1980 8946 5248 1269 0.213 1981 5165 4848 1215 0.260 1982 4145 4801 1446 0.306 1983 6588 4791 1498 0.356 1984 7878 4666 1370 0.326 1985 4254 4048 1409 0.370 1986 6449 3914 1419 0.347 1987 4190 3972 1280 0.304 1988 4113 3870 1444 0.354 1989 3154 3404 1390 0.435 1990 7917 3259 1315 0.390 1991 4405 2989 852 0.275 1992 3876 2824 895 0.259 1993 2601 2849 904 0.328 1994 3723 3195 800 0.247 1995 4461 3283 856 0.297 1996 3771 3072 833 0.249 1997 4982 2900 949 0.341 1998 3767 2963 880 0.313 1999 6944 2962 957 0.329 2000 5719 2930 1018 0.337 2001 3912 2892 1069 0.369 2002 5885 3053 1106 0.359 2003 2970 3036 1078 0.293 2004 4300 2785 1075 0.342 2005 5067 2883 1039 0.388 2006 4380 2413 1029 0.421 2007 3261 2427 983 0.452 2008 4401 2332

Average 4621 3502 965 0.282


5.4.14 Annex Excerpt from Council Regulation (EC) No. 509/2007 of 7 May 2007 establishing a multi-annual plan for the sustainable exploitation of the stock of sole in the Western Channel: Article 2 Objective 1. The multi-annual plan shall ensure the sustainable exploitation of the Western Channel sole stock. 2. This objective shall be attained by achieving and maintaining fishing mortality at a rate of 0,27 on appropriate agegroups. Article 3 Procedure for setting the Total Allowable Catches 1. For the years 2007, 2008 and 2009 the Council shall decide each year by qualified majority on the basis of a proposal from the Commission on Total Allowable Catches (TACs) for Western Channel sole at that level of catches which, according to a scientific evaluation carried out by the Scientific, Technical and Economic Committee for Fisheries (STECF), is the higher of:

(a) that TAC whose application will result in a 20 % reduction in the fishing mortality rate in 2007 compared to the average fishing mortality rate in the years 2003, 2004 and 2005 as most recently estimated by STECF; (b) that TAC whose application will result in the fishing mortality rate specified in Article 2(2).

2. For the years 2010, 2011 and 2012 the Council shall decide each year by qualified majority on the basis of a proposal from the Commission on TACs for Western Channel sole at that level of catches which, according to a scientific evaluation carried out by STECF, is the higher of:

(a) that TAC whose application will result in a 15 % reduction in the fishing mortality rate in 2010 compared to the average fishing mortality in the years 2007, 2008 and 2009 as most recently estimated by STECF; (b) that TAC whose application will result in the fishing mortality rate specified in Article 2(2).

3. For 2013 and subsequent years, the Council shall decide annually by qualified majority on the basis of a proposal from the Commission on TACs for Western Channel sole at that level of catches which, according to a scientific evaluation carried out by STECF, will result in the fishing mortality rate specified in Article 2(2). 4. Notwithstanding paragraph 3, if STECF advises that the fishing mortality rate specified in Article 2(2) has not been achieved by 31 December 2012, paragraph 2 shall apply, mutatis mutandis, for 2013, 2014 and 2015 and paragraph 3 shall apply mutatis mutandis from 2016. Article 4 Constraints on variation in TACs Starting with the first year of application of this Regulation, the following rules shall apply:

(a) where application of Article 3 would result in a TAC which exceeds the TAC of the preceding year by more than 15 %, the Council shall adopt a TAC which shall not be more than 15 % greater than the TAC of that year; (b) where application of Article 3 would result in a TAC which is more than 15 % less than the TAC of the preceding year, the Council shall adopt a TAC which is not more than 15 % less than the TAC of that year.


Article 5 Effort limitation 1. The TACs referred to in Chapter II shall be complemented by a system of fishing effort limitation based on the

geographical area and groupings of fishing gear, and the associated conditions for the use of these fishing opportunities specified in Annex IIc to Council Regulation (EC) No 41/2007 of 21 December 2006 fixing for 2007 the fishing opportunities and associated conditions for certain fish stocks and groups of fish stocks, applicable in Community waters and, for Community vessels, in waters where catch limitations are required.

2. The Council shall decide by a qualified majority, on the basis of a proposal from the Commission, on the maximum number of days at sea available for vessels present in the Western Channel and deploying beam trawls of mesh size equal to or greater than 80 mm and for vessels in the Western Channel deploying static nets with mesh size equal to or less than 220 mm.

3. The maximum number of days at sea referred to in paragraph 2 shall be adjusted in the same proportion as the adjustment in fishing mortality provided for in Article 3.

4. Notwithstanding paragraph 3, the fishing effort level to be established in each of the years 2008 and 2009 shall be maintained at the level established for 2007.


5.4.15 Irish Sea herring (Division VIIa (North))

The new landings and survey data available for this stock do not change the perception of the stock and do not give reason to change the advice from 2007. The advice for the fishery in 2009 is therefore the same as the advice given in 2007 for the 2008 fishery: “SSB is unknown but thought to be stable at a low level. The recent (2005 and 2006) catches of 4400 t do not appear to have been detrimental to the stock”. In addition, ICES offers the following consideration: The stock identity is complex as the juveniles mix with those of the Celtic Sea and the adults migrate from the Irish Sea after spawning. The stock identity has been reviewed by an EU-funded project WESTHER. Therefore, the assessment and advisory framework for this stock will be reviewed by a dedicated ICES study group in 2008 and 2009. Results of this work are expected to be available for the ICES advice in 2010. Source of information Report of the Herring Assessment Working Group for the Area South of 62°N, 11–19 March 2008 (ICES CM 2008/ACOM:02).

Year ICES Advice


Agreed TAC

ICES Catch

1987 TAC 4.3 4.5 5.8 1988 TAC (Revised advice in 1988) 10.5 (5.6) 10.5 10.2 1989 TAC 5.5 6.0 5.0 1990 Precautionary TAC 5.7 7.0 6.3 1991 TAC 5.6 6.0 4.4 1992 TAC 6.6 7.0 5.3 1993 TAC 4.9–7.4 7.0 4.4 1994 Precautionary TAC 5.3 7.0 4.8 1995 Precautionary TAC 5.1 7.0 5.1 1996 If required, precautionary TAC 5.0 7.0 5.3 1997 No advice given - 9.0 6.6 1998 Status quo F 6.5 9.0 4.9 1999 F=Proposed Fpa=0.36 4.9 6.6 4.1 2000 F=90% F(98)=0.31 3.9 5.4 2.0 2001 Status quo F= 0.26 5.1 6.9 5.5 2002 Average catch of 1996–2000 4.8 4.8 2.4 2003 2002 TAC 4.8 4.8 2.4 2004 Advice 2003 catch 4.8 4.8 2.5 2005 Status quo TAC 4.8 4.8 4.4 2006 Status quo TAC 4.8 4.8 4.4 2007 Status quo TAC 4.8 4.8 4.6 2008 Recent catches 4.4 4.8 2009 Same advice as last year 4.4

Weights in ‘000 t.


Table 5.4.15.1 Irish Sea herring in Division VIIa(N). Working group catch estimates in tonnes by country, 1987–2007*.

Country 1987 1988 1989 1990 1991 1992 1993 1994 1995

Ireland 1 200 2 579 1 430 1 699 80 406 0 0 0 UK 3 290 7 593 3 532 4 613 4 318 4 864 4 408 4 828 5 076 Unallocated 1 333 - - - - - - - - Total 5 823 10 172 4 962 6 312 4 398 5 270 4 408 4 828 5 076 Country 1996 1997 1998 1999 2000 2001 2002 2003 2004 Ireland 100 0 0 0 0 862 286 0 749 UK 5 180 6 651 4 905 4 127 2 002 4 599 2 107 2 399 1 782 Unallocated 22 - - - - - - - Total 5 302 6 651 4 905 4 127 2 002 5 461 2 393 2 399 2 531 Country 2005 2006 2007 Ireland 1 153 581 0 UK 3 234 3821 4 629 Unallocated - - Total 4 387 4 402 4 629

* The total catch does not in all cases correspond to the official statistics and cannot be used for management purposes.


5.4.16 Celtic Sea and Division VIIj herring

State of stock Spawning biomass in relation to precautionary limits




Comment

Uncertain, but likely at risk of reduced reproductive capacity

unknown unknown NA

The stock size is uncertain. The exploratory assessments indicate a decrease in SSB to a low level and an increase in F since the mid-1990s. The current stock size is likely as low as when it collapsed in the 1970s. The stock is currently composed mainly of younger fish. Management objectives There is no EU management plan for this stock. A local management committee manages the Irish fishery, and has the long-term aspiration to build the stock to a level that can sustain catches of 20 000 t per year. ICES has evaluated this objective and found that it is not attainable with the current levels of recruitment. Reference points Type Value Technical basis

Blim 26 000 t The lowest stock observed Bpa 44 000 t Low probability of low recruitment Flim Not defined


Fpa Not defined Targets Fy Not defined Single-stock exploitation boundaries Exploitation boundaries in relation to precautionary limits The current stock size is likely as low as when it collapsed in the 1970s. At recent levels of SSB there is a risk of reduced recruitment. Currently F is uncertain but too high and needs to be reduced. ICES recommends a rebuilding plan be put in place that will reduce catches. If no rebuilding plan is established, there should be no fishing. The rebuilding plan should be evaluated with respect to the precautionary approach. Management considerations Catches in recent years have been much lower than in earlier years, with recent removals among the lowest in the series. Fishing mortality of this stock has been high for many years, and probably well above possible long-term target F0.1 = 0.18 (estimated previously). From 1982 the stock was maintained with good recruitment up to the mid-1990s. SSB has declined steadily since 1990. In recent years, the fishery has relied on younger fish at 3, 4, and 5 years of age. The measures to protect first-time spawners by closing Division VIIaS should continue. Though it may not be possible to predict the success of this measure, it should be maintained for the next three years until 2010. Preliminary simulations in 2007 indicated that catches in the order of 10 000 t (roughly corresponding to the perceived current level of F = 0.6) are unlikely to guarantee recovery of the stock. These simulations also indicate that an F of around 0.4 is associated with uncertainty in recovery, while an F of 0.2 (~F0.1) is associated with a high likelihood of recovery. Under most circumstances a catch of around 5000 t appears to be appropriate to ensure that F = 0.2.


Some juveniles of this stock are present in the Irish Sea. Management of the Irish Sea herring fishery should ensure that catches of juveniles are avoided. Factors affecting the fisheries and the stock Regulations and their effects It is unclear if the timing of the triennial rotating spawning box closures coincides with peak spawning at present, and the impact of the closure is unknown. In 2008 Division VIIaS has been closed, except for a sentinel fishery. This means that only small dry-hold vessels using single trawls can fish in that area. This may result in a diversion of effort to the western grounds as it was not associated with accompanied catch reductions. Changes in fishing technology and fishing patterns The stock is exploited by two types of vessels, larger boats with refrigerated water/ice storage and smaller dry-hold vessels. The smaller vessels are confined to the spawning grounds (VIIaS and VIIg) during winter. The refrigerated hold vessels target the stock inshore in winter and offshore during the summer feeding phase (VIIg). There has been little fishing in Division VIIj in recent seasons, and there is evidence that stock abundance in this area is currently low. In recent years, the fleet has changed. The fleet size has reduced, with an increasing proportion of the catch being taken by refrigerated hold vessels and less by dry-hold vessels. There has been considerable efficiency creep in the fishery since the 1980s with greater ability to locate fish. It is thought that the collapse of the market for herring roe means that there is no longer the same incentive to discard (slip) catches in this fishery. Impacts of the environment on the fish stock Temperatures in this area have been increasing over the last number of decades, and indications are that salinity is also increasing. However, studies have been unable to demonstrate that changes in the environmental regime in the Celtic Sea have had any effect on the productivity of this stock. Scientific basis Data and methods Exploratory analyses use catch and acoustic survey data. The current management regime has resulted in catch data which are considered reasonably reliable. The acoustic time-series is imprecise as a result of the timing and the survey design. Celtic Sea and Division VIIj herring are assessed on a seasonal basis, 1 April to 31 March. This allows the inclusion of each season’s spawning cycle in a single assessment period. The TAC is set by calendar year. Uncertainties in assessment and forecast The exploratory assessments indicate a decrease in SSB to a low level and an increase in F since the mid-1990s. Recent history is uncertain because of the imprecise survey used to tune the assessment. The current small number of year classes in the stock exacerbates the uncertainty caused by the imprecise survey. Comparison with previous assessment and advice The perception of the stock status this year is similar to last year. The advice is the same as last year. Source of information Report of the Herring Assessment Working Group for the Area South of 62°N, 11–19 March 2008 (ICES CM 2008/ACOM:02).


ICES Predicted catch

Agreed Official ICES Year

Advice corresp. to advice

TAC Landings

Discards

Catch1

1987 Precautionary TAC 18 18 18 4.2 27.3 1988 TAC 13 18 17 2.4 19.2 1989 TAC 20 20 18 3.5 22.7 1990 TAC 15 17.5 17 2.5 20.2 1991 TAC (TAC excluding discards) 15 (12.5) 21 21 1.9 23.6 1992 TAC 27 21 19 2.1 23 1993 Precautionary TAC (including discards) 20–24 21 20 1.9 21.1 1994 Precautionary TAC (including discards) 20–24 21 19 1.7 19.1 1995 No specific advice - 21 18 0.7 19 1996 TAC 9.8 16.5–212 21 3 21.8 1997 If required, precautionary TAC < 25 22 20.7 0.7 18.8 1998 Catches below 25 < 25 22 20.5 0 20.3 1999 F = 0.4 19 21 19.4 0 18.1 2000 F < 0.3 20 21 18.8 0 18.3 2001 F < 0.34 17.9 20 19 0 17.7 2002 F<0.35 11 11 11.5 0 10.5 2003 Substantially less than recent catches - 13 12 0 11 2004 60% of average catch 1997–2000 11 13 12 - 11 2005 60% of average catch 1997–2000 11 13 10 - 8 2006 Further reduction 60% avg catch 2002–2004 6.7 11 9 - 8.5 2007 No fishing without rebuilding plan -- 9.4 9.6 - 8.2 2008 No targeted fishing without rebuilding plan -- 7.9 2009 No targeted fishing without rebuilding plan --

Weights in ‘000 t. 1) By calendar year. 2) Revised in 1996 after the ACFM May meeting.


Figure 5.4.16.1 Celtic Sea & Division VIIj herring. Plots are indicative of trends only, and there is uncertainty in

the most recent estimates of F, SSB, and recruitment (indicated by open symbols).

SSB

0

1958 1961 1964 1967 1970 1973 1976 1979 1982 1985 1988 1991 1994 1997 2000 2003

Mean F 2-7 ringers

0

0.2

0.4

0.6

0.8

1

1.2

1958 1963 1968 1973 1978 1983 1988 1993 1998 2003

Recruitment

0

1958196019621964196619681970197219741976197819801982198419861988

19901992199419961998200020022004


Figure 5.4.16.2 Herring in Celtic Sea and VIIj. Catches by assessment year.

0

10000

20000

30000

40000

50000

1958 1963 1968 1973 1978 1983 1988 1993 1998 2003

tonn

es


Table 5.4.16.1 Celtic Sea and Divisions VIIh, j, and k herring landings in tonnes by quota year, 1988–2004. (Data provided by Working Group members.) These figures may not in all cases correspond to the official statistics and cannot be used for management purposes. Year France Germany Ireland Netherlands U.K. Unallocated Discards Total 1988 - - 16,800 - - - 2,400 19,2001989 + - 16,000 1,900 - 1,300 3,500 22,7001990 + - 15,800 1,000 200 700 2,500 20,2001991 + 100 19,400 1,600 - 600 1,900 23,6001992 500 - 18,000 100 + 2,300 2,100 23,0001993 - - 19,000 1,300 + -1,100 1,900 21,1001994 + 200 17,400 1,300 + -1,500 1,700 19,1001995 200 200 18,000 100 + -200 700 19,0001996 1,000 0 18,600 1,000 - -1,800 3,000 21,8001997 1,300 0 18,000 1,400 - -2,600 700 18,8001998 + - 19,300 1,200 - -200 - 20,3001999 200 17,900 1300 + -1300 - 18,1002000 573 228 18,038 44 1 -617 - 18,2672001 1,359 219 17,729 - - -1578 - 17,7292002 734 - 10,550 257 - -991 - 10,5502003 800 - 10,875 692 14 -1,506 - 10,8752004 801 41 11,024 - - -801 - 11,0652005 821 150 8452 799 - -1770 - 8,4522006 - - 8,530 518 5 -523 - 8,5302007 581 248 8,268 463 63 -1355 - 8,268


Table 5.4.16.2 Celtic Sea and Division VIIj herring landings in tonnes by assessment year (1 April–31 March) 1988/1989–2004/2005. (Data provided by Working Group members.) These figures may not in all cases correspond to the official statistics and cannot be used for management purposes.

Year France Germany Ireland Netherlands U.K. Unallocated Discards Total 1988/1989 - - 17,000 - - - 3,400 20,4001989/1990 + - 15,000 1,900 - 2,600 3,600 23,1001990/1991 + - 15,000 1,000 200 700 1,700 18,6001991/1992 500 100 21,400 1,600 - -100 2,100 25,6001992/1993 - - 18,000 1,300 - -100 2,000 21,2001993/1994 - - 16,600 1,300 + -1,100 1,800 18,6001994/1995 + 200 17,400 1,300 + -1,500 1,900 19,3001995/1996 200 200 20,000 100 + -200 3,000 23,3001996/1997 1,000 - 17,900 1,000 - -1,800 750 18,8001997/1998 1,300 - 19,900 1,400 - -2100 - 20,5001998/1999 + - 17,700 1,200 - -700 - 18,2001999/2000 200 18,300 1300 + -1300 - 18,5002000/2001 573 228 16,962 44 1 -617 - 17,1912001/2002 - - 15,236 - - - - 15,2362002/2003 734 - 7,465 257 - -991 - 7,4652003/2004 800 - 11,536 610 14 -1,424 - 11,5362004/2005 801 41 12,702 - - -801 - 12,7432005/2006 821 150 9,494 799 - -1770 - 9,4942006/2007 - - 6,944 518 5 -523 - 6,9442007/2008 379 248 7,636 327 - -954 - 7,636


5.4.17 Herring in Divisions VIa (South) and VIIb, c The updated exploratory assessment available for this stock does not change the perception of the stock and does not give reason to change the advice from 2007. The advice for the fishery in 2009 is therefore the same as the advice given in 2007 for the 2008 fishery: “ICES recommends a rebuilding plan be put in place that will reduce catches. If no rebuilding plan is established, there should be no fishing. The rebuilding plan should be evaluated with respect to the precautionary approach”. In addition, ICES offers the following considerations: The stock identity is complex as the juveniles mix with those from the west of Scotland and the adults mix with those from the Irish Sea and Division VIaN over the shelf areas to the west of Scotland after spawning. The stock identity has been reviewed by an EU-funded project WESTHER. Therefore, the assessment and advisory framework for this stock will be reviewed by a dedicated ICES study group in 2008 and 2009. The results of this work are expected to be available for the ICES advice in 2010. There is no explicit management plan for this stock. The local Irish management committee developed the objective to rebuild the stock to above Bpa and has a long-term objective to achieve catches of 25 000 t per year. Although there is little information on recruitment available, it is unlikely that it is above average and it may possibly be below average. The long-term catch aspiration of the local management committee is not likely to be achievable at current stock productivity. Source of information Report of the Herring Assessment Working Group for the Area South of 62°N, 11–19 March 2008 (ICES CM 2008/ACOM:02).

Weights in ‘000 tonnes. * 2007 advice revised to be consistent with the single-stock exploitation boundaries.

Year ICES Advice

Predicted catch corresp. to

advice

AgreedTAC

Official Landings

Disc. slip.

ICES Catch

1987 TAC 18 17 17 - 49 1988 TAC depending on whether 1987 TAC is taken 11–18 14 15 - 29 1989 TAC 15 20 21 1.0 29 1990 TAC depending on whether 1989 TAC is taken 25–27 27.5 28 2.5 44 1991 TAC < 26 27.5 23 3.4 38 1992 TAC (including discards) 29 28 27 0.1 32 1993 Precautionary TAC (including discards) 29 28 30 0.3 37 1994 Precautionary TAC 28 28 27 0.7 34 1995 Precautionary TAC (including discards) 36 28 27 - 28 1996 If required, precautionary TAC 34 28 25 - 33 1997 Catches below 25 < 25 28 28 0.1 27 1998 Catches below 25 < 25 28 28 - 39 1999 F 70% of F(97) 19 21 18 - 26 2000 F 40% of F(98) =Proposed Fpa 14 14 10 - 19 2001 F 40% of F(99) F = 0.2 14 14 13 - 14 2002 No increase in catches 14 14 14 - 17 2003 No increase in catches 14 14 14 - 16 2004 No increase in catches 14 14 11 - 13 2005 No increase in catches 14 14 13 - 16 2006 No increase in catches 14 15.4 15.2 - 19 2007 No fishing without a rebuilding plan* - 13.8 12.6 - 17.7 2008 No fishing without a rebuilding plan* - 11.6 2009 Same advice as last year -


Table 5.4.17.1 Herring in Divisions VIaS and VIIbc. Landings in tonnes by quota year, 1988–2007. (Data provided by Working Group members.) These figures may not in all cases correspond to the official statistics and cannot be used for management purposes.

Country 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 France - - + - - - - - - - - - Germany, Fed.Rep.

- - - - 250 - - 11 - - - -

Ireland 15000 18200 25000 22500 26000 27600 24400 25450 23800 24400 25200 16325 Netherlands 300 2900 2533 600 900 2500 2500 1207 1800 3400 2500 1868 UK (N.Ireland)

- - 80 - - - - - - - - -

UK (England + Wales)

- - - - - - 50 24 - - - -

UK Scotland - + - + - 200 - - - - - - Total landings

15300 21100 27613 23100 27150 30300 26950 26692 25600 27800 27700 18193

Unallocated/ area misreported

13800 7100 13826 11200 4600 6250 6250 1100 6900 -700 11200 7916

Discards - 1000 2530 3400 100 250 700 - - 50 WG catch 29100 29200 43969 37700 31850 36800 33900 27792 32500 27150 38900 26109 Country 2000 2001 2002 2003 2004 2005 2006 2007 France - - 515 - - - - - Germany, Fed.Rep.

- - - - - - - -

Ireland 10164 11278 13072 12921 10950 13351 14840 12662 Netherlands 1234 2088 366 - 64 - 353 13 UK (N.Ireland)

- - - - - - - -

UK (England + Wales)

- - - - - - - -

UK Scotland - - - - - - 6 - Total landings

11398 13366 13953 12921 11014 13351 15199 12675

Area misreported 8448 1390 3873 3581 2813 2880 4353 5129 Unallocated -353 -13 Discards - - - - - - WG catch 19846 14756 17826 16502 13827 16231 19193 17791


5.4.18 Sprat in Divisions VIId,e

Single-stock exploitation boundaries As last year, the available information is inadequate to evaluate stock trends and therefore the state of the stock is unknown. This assessment will not be updated until more information is available. Source of information Report of the Herring Assessment Working Group for the Area South of 62°N, 11–19 March 2008 (ICES CM 2008/ACOM:02).

Year ICES

Advice Predicted catch

corresp. to advice Agreed TAC

ICES Catch

1987 No advice - 5 2.7 1988 No advice - 5 5.5 1989 No advice - 12 3.4 1990 No advice - 12 2.1 1991 No advice - 12 2.6 1992 No advice - 12 1.8 1993 No advice - 12 1.8 1994 No advice - 12 3.2 1995 No advice - 12 1.5 1996 No advice - 12 1.8 1997 No advice - 12 1.6 1998 No advice - 12 2.0 1999 No advice - 6.3 3.6 2000 No advice - 12 1.7 2001 No advice - 12 1.3 2002 No advice - 12 1.2 2003 No advice - 9.6 1.4 2004 No advice - 9.6 0.8 2005 No advice - 7.7 1.6 2006 No advice - 6.1 1.9 2007 No advice - 6.1 1.8 2008 No advice - 6.1 2009 Same as last year -

Weights in ‘000 tonnes.


Table 5.4.18.1 Sprat in Divisions VIId,e. Nominal catches of sprat in VIId,e from 1985–2007.

Country

1985 1986 1987 1988 1989 1990 1991 1992

Denmark 15 250 2 529 2 092 608 France 14 23 2 10 35 Netherlands UK (Engl.&Wales) 3 771 1 163 2 441 2 944 1 319 1 508 2 567 1 790 Total 3 785 1 178 2 714 5 475 3 421 2 116 2 567 1 825 Country 1993 1994 1995 1996 1997 1998* 1999* 2000* Denmark France 2 1 0 18 Netherlands 1 1 UK (Engl.&Wales) 1 798 3 177 1 515 1 789 1 621 2 024 3 559 1 692 Total 1 800 3 178 1 515 1 789 1 621 2 024 3 560 1 711 Country 2001 2002 2003 2004 2005 2006 2007 Denmark France Netherlands UK (Engl.&Wales) 1 349 1 196 1 377 836 1 635 1 974 1819 Total 1 349 1 196 1 377 836 1 635 1 974 1819 * Preliminary


5.4.19 Megrim (Lepidorhombus whiffiagonis) in Divisions VIIb–k and VIIIa,b,d

The new survey data available for this stock do not change the perception of the stock and do not give reason to change the advice from 2007. The advice on this stock for the fishery in 2009 is therefore the same as the advice given in 2007 for the 2008 fishery: “The current stock status is unknown, but survey indicators and commercial data series point to the stock being stable. Therefore ICES recommends that the landings of L. whiffiagonis in 2009 should not exceed the average landings of 2004–2006. This corresponds to landings lower than 13 000 tonnes.” This advice will be updated in 2009. Source of information Report of the Working Group on the Assessment of Southern Shelf Stocks of Hake, Monk, and Megrim 30 April–6 May 2008 (ICES CM 2008/ACOM:07). Year ICES


Predicted catch

corresp. To advice

Predicted catch

corresponding to single-stock

boundaries

Agreed TAC1

ICES Landings

Disc. Slip.

ICES Catch

1987 Not assessed - 16.46 17.1 1.7 18.8 1988 Not assessed - 18.1 17.6 1.7 19.3 1989 Not assessed - 18.1 19.2 2.6 21.8 1990 Not assessed - 18.1 14.4 3.3 17.7 1991 No advice - 18.1 15.1 3.3 18.4 1992 No advice - 18.1 15.6 3.0 18.6 1993 Within safe biological

limits - 21.46 14.9 3.1 18.0

1994 Within safe biological limits

- 20.33 13.7 2.7 16.4

1995 No particular concern - 22.59 15.9 3.2 19.1 1996 No long-term gain in

increased F 16.6 21.20 15.1 3.0 18.1

1997 No advice 14.3 25.0 14.3 3.1 17.3 1998 No increase in F 15.2 25.0 14.3 5.4 19.7 1999 Reduce F below Fpa 14.61 25.0 13.7 3.1 16.9 2000 Reduce F below Fpa <14.21 20.0 15.0 2.3 17.3 2001 Reduce F below Fpa < 14.11 16.8 15.8 1.3 17.1 2002 Reduce F below Fpa < 13.01 14.9 15.9 1.5 17.4 2003 Reduce F below Fpa < 16.11 16.0 15.6 3.1 18.8 2004 Reduce F below Fpa < 20.21 20.2 14.3 4.5 18.8 2005 Reduce F below Fpa < 22.61 21.5 12.7 1.8 14.5 2006 Reduce F below Fpa <13.61 20.4 12.0 2.5 14.5 2007 Less than average

landings 2003–05 < 14.21 20.4 13.3 2.2 15.6

2008 Less than average landings 2004–06

< 13.01 20.4

2009 Same advice as last year

< 13.01

Weights in ‘000 t. 1Includes L. boscii.


5.4.20 Anglerfish in Divisions VIIb–k and VIIIa,b,d (Lophius piscatorius and L. budegassa)

Single-stock exploitation boundaries The landings and survey information for these stocks does not change the perception of the stocks and does not give reason to change the advice from 2007. The advice on these stocks for the fishery in 2009 is therefore the same as the advice given in 2007 for the 2008 fishery: “The current stock status is unknown relative to precautionary reference points, but indicators point to the stocks being stable. Therefore ICES recommends that the landings [..] should not exceed the average landings of 2004–2006. This corresponds to a TAC for both species combined of lower than 33 000 tonnes.” This advice will be updated in 2009. Source of information Report of the Working Group on the Assessment of Southern Shelf Stocks of Hake, Monk, and Megrim, 30 April–6 May 2008 (ICES CM 2008/ACOM:07). Year ICES

Advice Single-Stock

Exploitation Boundaries

Predicted catch

corresp. To Single-

Stock Exploitation Boundaries

Predicted catch

corresp. To

advice

AgreedTAC1,2

ICES Landings

2

Landings of

L. piscat.

Landings of

L. budeg.

1987 Not assessed - 39.08 29.5 21.9 7.6 1988 Not assessed - 42.99 28.5 20.1 8.4 1989 Not assessed - 42.99 30.0 20.5 9.5 1990 Not assessed - 42.99 29.4 19.8 9.6 1991 No advice - 42.99 25.1 16.2 8.8 1992 No advice - 42.99 21.1 12.8 8.3 1993 Concern about L. pisc. SSB

decrease - 25.1 20.1 13.5 6.7

1994 SSB decreasing, still inside safe biological limits

- 23.9 21.9 16.1 5.8

1995 No increase in F 20.0 23.2 26.8 19.7 7.1 1996 No increase in F 30.3 30.4 30.2 22.1 8.1 1997 No increase in F 34.3 34.3 29.8 21.7 8.1 1998 No increase in F 33.0 34.3 28.2 19.6 8.6 1999 No increase in F 32.9 34.3 25.03 17.63 7.43 2000 At least 20% decrease in F < 22.3 29.6 20.63 14.03 6.63 2001 Reduce F below Fpa < 27.6 27.6 22.63 16.83 5.83 2002 Reduce F below Fpa < 19.9 23.7 26.43 20.03 6.5 2003 At least 30% decrease in F < 16.4 21.04 33.23 24.93 8.43 2004 At least 10% decrease in F < 26.7 26.7 35.13 27.73 7.53

2005 Maintain F below Fpa < 37.8 31.2 32.83 25.33 7.53 2006 Maintain F below Fpa <33.9 34.0 31.23 25.53 5.73

2007 Maintain F below Fpa <36.0 36.0 36.1 29.7 6.4

2008 Less than average landings <33.0 36.0

2009 Same advice as last year <33.0

Weights in ‘000 t. 1 Includes Division VIIa and Divisions VIIId,e. 2 Applies to both species. 3 Revised. 4 TAC was changed during 2003 from 19 400 t to 21 000 t following fast-track advice from ICES.


5.4.21 Cod in Division VIa (West of Scotland)





Comment


Unknown Unknown Not defined Total mortality cannot be accurately partitioned into fishing mortality and natural mortality

Based on the most recent estimates of SSB (in 2008) ICES classifies the stock as suffering reduced reproductive capacity. Total mortality is probably high but cannot be accurately partitioned into fishing mortality and natural mortality. The spawning-stock biomass has increased from an all time low in 2006 but remains well below Blim. Recruitment has been estimated to be low over the last decade. The 2005 year class is estimated to be the largest for that decade, but still below the long-term average. Management objectives The European Commission has enacted a Council Regulation ((EC) No. 423/2004) which establishes measures for the recovery of cod stocks: For stocks above Blim, the harvest control rule (HCR) requires:

1. setting a TAC that achieves a 30% increase in the SSB from one year to the next, 2. limiting annual changes in TAC to ± 15% (except in the first year of application), and, 3. a rate of fishing mortality that does not exceed Fpa.

For stocks below Blim the Regulation specifies that:

1. conditions 1-3 will apply when they are expected to result in an increase in SSB above Blim in the year of application,

2. a TAC will be set lower than that calculated under conditions 1-3 when the application of conditions 1-3 is not expected to result in an increase in SSB above Blim in the year of application.

The European Commission has adopted a proposal in April 2008 to amend the EU cod recovery plan (COM(2008) 162 final). ICES has previously concluded that a precautionary recovery plan must include an adaptive element implying that fisheries for cod remain closed until an initial recovery of the cod SSB has been proven. Such an element of zero catch is not included in the existing plan. ICES therefore considers the recovery plan to be not consistent with the precautionary approach. Reference points Type Value Technical basis

Blim 14 000 t Blim = Bloss, the lowest observed spawning stock estimated in previous assessments.

Bpa 22 000 t This is considered to be the minimum SSB required to ensure a high probability of maintaining SSB above Blim, taking into account the uncertainty of assessments. This also corresponds with the lowest range of SSB during the earlier, more productive historical period.

Flim 0.8 Fishing mortalities above this have historically led to stock decline.


Fpa 0.6 This F is considered to have a high probability of avoiding Flim. Targets Fy Not defined. (unchanged since: 1998)


Single-stock exploitation boundaries Exploitation boundaries in relation to existing management plans The management plan is not explicit about the level of reduction in the catch when the stock is below Blim. Furthermore, due to the uncertainty in the level of fishing mortality, ICES is not in a position to give quantitative forecasts. Simulations conducted in 2006 showed that fishing should be closed for 3 years in order to bring SSB above Blim. Exploitation boundaries in relation to precautionary considerations Given the low SSB and low recruitments in recent years, it is not possible to identify any non-zero catch which would be compatible with the precautionary approach. Short-term implications Because of uncertainties in the level and trend of natural mortality it is not possible to partition F from other sources of mortality. A short-term forecast was performed to consider projections of SSB under different levels of removals. Even under the option of zero removals SSB was predicted to still be below Blim in 2010. Management considerations Cod is taken in mixed demersal fisheries, and in Division VIa it is now regarded as a bycatch species. Following the advice for zero catch of cod will likely result in having to greatly reduce harvesting of other stocks such as haddock, whiting, and anglerfish. Results from the STECF meeting on the assessment of the fishing effort regime (STECF, 2007a) showed bycatch of cod from vessels targeting Nephrops to have declined to a low level in recent years. The amount of bycatch from this fleet needs to continue to be monitored (including discard observations) in case of a future increase in catch of cod from vessels targeting Nephrops. The most recent (2005) data available on landings by ICES statistical rectangle show that all significant landings come from statistical rectangles west of the ‘west of Scotland management line’, or from rectangles bisected by that line. It is therefore possible that the majority of cod landings from Division VIa could be from vessels unaffected by cod recovery measures and unrestricted in their catch composition. It is important that cod recovery measures include all areas occupied by the depleted stock. There are indications that because of new legislation, misreporting has reduced from the beginning of 2006 (see Regulations and their effects below). Fishery discard data show increased discards at ages one and two and a change in discard practices such that fish are discarded at older ages. This suggests the legislation has controlled landings rather than catch. It is important that good observer coverage is provided in Division VIa to record discard trends in future. Management plan evaluations Simulations conducted by ICES (2006) showed that, starting in 2007, the fishery would need to be closed for 3 years in order to bring SSB above Blim with high probability. Impacts of fisheries on the ecosystems For a general description of the impacts of the demersal trawl fishery in ICES Division VIa see the overview. Cod is taken in mixed demersal fisheries and there are no impacts specific to the catching of cod. Factors affecting the fisheries and the stock Regulations and their effects The fishery is managed by a combination of TAC, area closures, technical measures, and effort restrictions. These do not seem to have been effective in controlling catches or sufficient to rebuild the stock to precautionary levels. Area closures

• Clyde Sea area closure – STECF (2007b) noted that the Clyde closure includes the main spawning area of a reproductively isolated aggregation of cod and concluded that the closure is likely to have a positive effect in reducing targeting of high densities of mature cod.


• Windsock closed area – STECF (2007b) concluded that the extent of the Windsock closure is unlikely to be large enough to greatly reduce fishing mortality on cod, and its boundaries should be reconsidered. However, its removal would not help improve cod recovery.

Mesh sizes

• Change from 100 to 120 mm for vessels fishing for cod (Reg. (EC) 2056/2001) – The increase in minimum mesh size from 100 to 120 mm caused vessels to shift from the whitefish to the Nephrops targeted fishing sector. This resulted in an increase in effort using 80 mm mesh.

Effort limitations

• Days-at-sea allowances currently implemented under Annex IIa of Reg. (EC) 40/2008 – The restrictions are targeted primarily at gears taking the largest catches of cod. For gears with mesh sizes of 70–89 mm and 90–99 mm this has led to days-at-sea limits between two and three times greater than the limits for gears with mesh sizes of 100–119 mm or ≥ 120 mm. The introduction of effort regulation has effectively further encouraged vessel operators to reduce mesh size and shift to other fisheries, particularly Nephrops trawling, in order to gain more days at sea.

• Catch composition rules related to days-at-sea allowances (Reg. (EC) 850/1998 Annex I and Reg. (EC) 2056/2001) – These rules legislate for landings compositions but do not restrict discards.

Supply chain traceability

• U.K. “Buyers and Sellers” regulation and Irish “Sales Note” regulation – Unreported landings are expected to have reduced under these regulations. Observer data, however, show an increase in discards starting in 2006. The amount of discards relative to landings has increased and the age pattern of discarding has changed. Currently discards of fish aged 3 and above are being recorded.

In Scotland the ‘Conservation Credits Scheme’ was implemented from the beginning of February 2008 and essentially grants vessels their 2007 allocation of days (operated as hours at sea) in return for observance of measures to avoid cod catch. Adherence to the measures under this scheme is not mandatory and it is too early for ICES to comment on the success of the measures in aiding cod recovery. Changes in fishing technology and fishing patterns In 2007 there has been a shift away from the traditional whitefish fishery in ICES Division VIa and into the Nephrops fishery in Division IVa by vessels that were using 100–110 mm mesh west of Scotland. Rising fuel costs are influencing the choice of gear deployed. There have been instances of changes from twin trawl to single trawl and an increase in the use of pair trawl/seine. Some vessels operating in the Division VIa Nephrops fleet have adopted a 100–110 mm square mesh panel. This gives a theoretical 10% increase in the mean length of cod captured. However, to be most effective the square mesh panel should be installed close to the codend of the net, whereas some of the installed square mesh panel have been placed some distance from the codend. There has been some reduction in the number of Irish vessels as a result of decommissioning. Impacts of the environment on the fish stock ICES (2008) reported on the general warming trend of the Northern Shelf waters. A negative impact on recruitment with rising sea temperature has been shown for cod in the warmer waters of this species’ range, including cod west of Scotland (Brunel and Boucher, 2007). Seal abundance has increased west of Scotland over the recent decades. Seals are known to feed on cod, amongst other species, and the mortality of cod due to seal predation is likely to have increased in recent years. However, the contribution of seal predation to total cod mortality is not known.


Scientific basis Data and methods A catch-at-age model using catch data up to 1994 tuned by survey data and utilizing survey information alone from 1995 onward was used to evaluate trends in spawning-stock biomass and recruitment. Trends in SSB are similar to the results obtained from a model based on survey data alone. Estimates of mortality are those from total removals, i.e. fishing mortality plus unaccounted mortality. Discards-at-age data are provided by Scotland only. Uncertainties in assessment and forecast Landings data are considered to be very uncertain, due to incorrect reporting of landings (species and quantity). There are indications that misreporting has reduced from the beginning of 2006. In the current set-up of the assessment model discard information is removed for the same years for which landings data is removed. The increase in discards at ages one and two in 2006 and 2007 is not accounted for in the assessment. Survey information shows that the total removal of cod in Division VIa may have been underestimated in the past decade relative to earlier periods. In an attempt to remove bias in the assessment a catch-at-age model was used that ignored landings and discard numbers from 1995 onwards, relying on survey data for this later period. It is, however, considered that mortality estimates arising from this assessment heavily or wholly based on survey data are poorly estimated. In contrast, historical trends in spawning biomass and recruitment appear to be robust measures of stock dynamics, see Figure 5.4.21.3. Only a single survey series is considered of sufficient quality for use in the assessment and the values of the indices have high variability. This causes estimation of mortality-at-age to be uncertain in particular. Because of uncertainties in the level and trend of natural mortality it is not possible to predict landings estimates from the forecast, only removals associated with both fishing and unaccounted natural mortality. Comparison with previous assessment and advice The perception of the state of the stock remains unchanged. Although recruitment of the 2005 year class has been revised upwards and the strength of this year class has resulted in estimated SSB increasing from 2006 to 2007 and again from 2007 to 2008, forecasts still put SSB below Blim in 2009 and 2010. The advice is the same as last year. Sources of information Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 15-21 May 2008 (ICES CM 2008/ACOM:08). Brunel, T., and Boucher, J. 2007. Long-term trends in fish recruitment in the north-east Atlantic related to climate change. Fisheries Oceanography, 16(4): 336–349. Hammond, P. S., and Harris, R. N. 2006. Grey seal diet composition and prey consumption off western Scotland and Shetland. Final report to Scottish Executive Environment and Rural Affairs Department and Scottish Natural Heritage. ICES. 2006. Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks (WGNSDS), 9–18 May 2006, ICES Headquarters, Denmark. ICES CM 2006/ACFM:30. 870 pp. ICES. 2008. Report of the Working Group for Regional Ecosystem Description (WGRED), 25–29 February 2008, ICES, Copenhagen, Denmark. ICES CM 2008/ACOM:47. 203 pp. STECF. 2007a. STECF sub group SGRST on Fishing Effort Regime, Lisbon 21–25 June 2007 and Ispra, 24–28 September 2007. STECF. 2007b. Evaluation of closed area schemes (SGMOS-07-03).


Year ICES advice Single-stock

exploitation boundaries

Predicted catch

corresp. to advice

Predicted catch

corresp. to single-stock boundaries

Agreed TAC1

Official landings

ICES Landings

1987 Reduce F towards Fmax 18.0 22.0 19.2 19.0 1988 No increase in F; TAC 16.0 18.4 19.2 20.4 1989 80% of F(87); TAC 16.0 18.4 15.4 17.2 1990 80% of F(88); TAC 15.0 16.0 11.8 12.2 1991 70% of effort (89) - 16.0 10.6 10.92

1992 70% of effort (89) - 13.5 9.0 9.73 1993 70% of effort (89) - 14.0 10.5 11.83 1994 30% reduction in effort - 13.0 9.1 10.83 1995 Significant reduction in

effort - 13.0 9.7 9.63

1996 Significant reduction in effort

- 13.0 9.6 9.4


- 14.0 7.0 7.0

1998 20% reduction in F 9.55 11.0 5.7 5.7 1999 F reduced to below Fpa <9.75 11.8 4.3 4.2 2000 Recovery plan, 60%

reduction in F <4.2 7.48 2.84 3.0

2001 Lowest possible F, recovery plan

- 3.7 2.5 2.3

2002 Recovery plan or lowest possible F

- 4.6 2.0 2.1

2003 Closure - 1.81 1.3 n/a 2004 Zero catch 6 0 0.85 0.6 n/a 2005 Zero catch 6 0.72 0.5 n/a 2006 Zero catch 6 0.613 0.5 n/a 2007 Zero catch 6 0 0.49 0.5 n/a 2008 Zero catch 6 0 0.402 n/a 2009 Zero catch 6 0

Weights in ‘000 t. 1TAC is for the whole of Subdivision Vb1 and Subareas VI, XII, and XIV. 2Not including misreporting. 3Including ICES estimates of misreporting. 4Incomplete data. 5For Division VIa only. 6 Single-stock boundaries and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits.


Figure 5.4.21.1 Cod in Division VIa. Summary plot of TSA final run (landings and discard data excluded from

1995 onward). In the catch figure, open circles indicate observed catches, and lines indicate estimated removals. Estimates are plotted with approximate point-wise 95% confidence bounds. The vertical line in each plot delineates the last year of the historical assessment (2007); estimates to the right of these lines are the TSA-based forecast using status quo removal.


Stock - Recruitment

0

10

20

30

40

50

60

70

0 10 20 30 40

SSB in 1000 t

Rec

ruitm

ent (

age

1) in

m

illio

ns SSB-Rec.

Blim

Bpa

Figure 5.4.21.2 Cod in Division VIa. Stock and recruitment relationship.

Cod in Division VIa (West of Scotland)

0

5

10

15

20

25

30

35

40

1990 1995 2000 2005

SSB ('000 tonnes)

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

1.60

1.80

2.00

1990 1995 2000 2005


Figure 5.4.21.3 Cod in Division VIa. Comparison of current assessment with previous assessments (SSB and

recruitment only).

ICES

Adv

ice

2008

, Boo

k 5

149

Tab

le 5

.4.2

1.1

Cod

in D

ivis

ion

VIa

. Off

icia

l cat

ch st

atis

tics i

n 19

85–2

007,

as r

epor

ted

to IC

ES.

Cou

ntry

20

03

2004

20

0520

0620

07*

Bel

gium

D

enm

ark

Faro

e Is

land

s

2 0

112

Fran

ce

172

91

107

101

81G

erm

any

+

22

Ir

elan

d 12

0 34

28

1870

Net

herla

nds

-

Nor

way

45

10

17

3030

Spai

n 3

U

K (E

., W

., N

.I.)

79

46

259

UK

(Sco

tland

) 87

9 41

3 24

327

4U

K

33

2To

tal l

andi

ngs

1,29

8 5

96

420

484

479

* Pr

elim

inar

y.

Cou

ntry

19

85

1986

19

8719

8819

8919

9019

9119

9219

93

1994

1995

1996

1997

1998

1999

2000

2001

20

02

Bel

gium

48

88

33

4428

-6

-22

1

2+

111

++

2 +

Den

mar

k -

- 4

13

22

32

+4

2-

-+

--

- Fa

roe

Isla

nds

- -

-11

26-

--

- -

--

--

--

- -

Fran

ce

7,41

1 5,

096

5,04

47,

669

3,64

02,

220

2,50

31,

957

3,04

7 2,

488

2,53

32,

253

956

714*

842*

236

391

208

Ger

man

y 66

53

12

2528

158

660

594

10

018

635

68

64

+ Ir

elan

d 2,

564

1,70

4 2,

442

2,55

11,

642

1,20

076

176

164

5 82

51,

054

1,28

670

847

822

335

731

9 21

0 N

ethe

rland

s -

- -

--

--

--

--

-2

1-

--

- N

orw

ay

204

174

7718

620

715

040

171

72

5161

137

3636

7911

4*40

* 88

Sp

ain

28

- -

-85

--

--

-16

+6

4245

143

11

UK

(E.,

W.,

N.I.

) 26

0 16

0 44

423

027

823

051

157

752

4 41

945

045

777

947

438

128

013

8 19

5 U

K (S

cotla

nd)

8,03

2 4,

251

11,1

438,

465

9,23

67,

389

6,75

15,

543

6,06

9 5,

247

5,52

25,

382

4,48

93,

919

2,71

12,

057

1,54

4 1,

519

UK

Tota

l lan

ding

s 18

,613

11

,526

19

,199

19

,182

15

,426

11

,777

10

,634

9,

017

10,4

75

9,13

1 9,

660

9,58

0 6,

992

5,67

1 4,

289

2,76

7 2,

439

2,23

1



Table 5.4.21.2 Cod in Division VIa (West of Scotland).

Year Recruitment SSB Total Removals Mean Z Age 1 Ages 2–5 thousands tonnes tonnes

1978 20720 26005 17352 0.898 1979 28456 28436 26738 1.085 1980 31326 31744 23974 0.921 1981 10592 38026 24197 0.913 1982 25884 37448 25934 0.972 1983 15657 32041 22750 1.049 1984 24168 29908 24424 1.104 1985 12488 22060 17379 1.201 1986 19214 18469 13670 1.019 1987 61243 19681 21148 1.151 1988 6170 23462 18700 1.088 1989 19870 21013 17178 1.132 1990 6466 17745 12368 1.007 1991 11286 15214 11670 1.097 1992 17407 12441 10005 1.075 1993 7188 14588 11530 1.035 1994 15154 15183 11208 0.926 1995 12681 16741 12468 1.006 1996 5008 17576 12495 1.049 1997 17766 14073 12106 1.063 1998 8727 11920 9609 1.076 1999 4933 11748 8561 1.071 2000 10315 10163 7759 1.026 2001 3288 9040 6465 1.067 2002 8915 7732 6418 1.071 2003 1793 6570 4925 1.097 2004 4250 5275 3936 0.920 2005 5487 3829 3544 0.938 2006 11600 3742 3769 0.833 2007 2377 6276 4499 0.788 2008 3877 7470

Average 14010 17278 13559 0.849


5.4.22 Cod in Division VIb (Rockall)

State of the stock Officially reported catches are shown in the table below. The available information is inadequate to evaluate stock trends and there is no basis for an advice. Source of information Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 15–21 May 2008 (ICES CM 2008/ACOM:08). Table 5.4.22.1 Cod in Division VIb (Rockall). Official catch statistics. Values in t.

Cou

ntry

Faro

e Is

land

s

Fran

ce

Ger

man

y

Irel

and

Nor

way

Portu

gal

Rus

sia

Spai

n

UK

(E. &

W. &

N

.I.)

UK

(Sco

tland

)

UK

Tota

l

1984 18 9 - - 373 - - 241 161 221 1023 1985 - 17 3 - 202 - - 1200 114 437 1973 1986 1 5 - - 95 - - 1219 93 187 1600 1987 - 7 - - 130 - - 808 69 284 1298 1988 31 2 3 - 195 - - 1345 56 254 1886 1989 5 - - - 148 - - - 131 265 549 1990 - - - 400 119 - - 64 8 758 1349 1991 - - 126 236 312 - - 70 23 829 1596 1992 - - 2 235 199 - - - 26 714 1176 1993 1 - - 472 199 - - - 103 322 1097 1994 - - - 280 120 - - - 25 236 661 1995 - - - 477 92 - - 2 90 370 1031 1996 - - 10 436 91 - - 5 23 210 775 1997 - - 22 153 55* 5 - 1 20 706 962 1998 - - 3 227 51* - - 6 32 341 660 1999 - - 11 148 85* - - 4 22 389 659 2000 n/a + 1 119 152* - 7 3 4 286 572 2001 n/a + - 40 89 - 26 1 2 176 334 2002 n/a 1 - 18 28 - - 2 67 115 2003 11 25 6 3 57 102 2004 7 23 45 75 2005 0.08 12 7 43 62 2006 23 7 29 58

2007* - - - 24 12 - - - 26 62 * Preliminary values.


5.4.23 Haddock in Division VIa (West of Scotland)

State of the stock

Spawning biomass in relation to precautionary limits




Comment

Increased risk Increased risk Overfished NA

Based on the most recent estimate of SSB (in 2008) and fishing mortality (in 2007) ICES classifies the stock as being at risk of reduced reproductive capacity and at risk of being harvested unsustainably. The very strong 1999 year class caused SSB to increase from a level near the historic low in 2000 to a peak in 2003, but it has declined since. F has been above Fpa in most years since 1987. The 2003 to 2006 year classes are estimated to be weak. The 2005 year class is of moderate strength. Management objectives There are no explicit management objectives for this stock. Reference points Type Value Technical basis


Bpa 30 000 t Bpa = Blim * 1.4. This is considered to be the minimum SSB required to have a high probability of maintaining SSB above Blim, taking into account the uncertainty of assessments.

Flim Not defined.


Fpa 0.5 The F below which there is a high probability of avoiding SSB<Bpa in the long term.

Targets Fy Not defined. (unchanged since: 1998) Yield and spawning biomass per Recruit F-reference points: Fish Mort Yield/R SSB/R Ages 2–6 Average last 3 years 0.59 0.17 0.32

Fmax 0.40 0.17 0.46 F0.1 0.19 0.15 0.84 Fmed 0.45 0.17 0.42

Candidates for reference points consistent with taking high long-term yields and achieving a low risk of depleting the productive potential of the stock may be identified in the range of F0.1–Fmax. Single-stock exploitation boundaries Exploitation boundaries in relation to high long-term yield, low risk of depletion of production potential and considering ecosystem effects The current fishing mortality (2007) is estimated to be 0.56, which is above the rate expected to lead to high long-term yields and low risk of stock depletion. Exploitation boundaries in relation to precautionary limits Even in the absence of fishing the stock is not expected to be rebuilt to Bpa.


Conclusion on exploitation boundaries Given the recent poor recruitment and the rapidly declining SSB, the forecast indicates that a zero fishing mortality in 2009 will not maintain the stock above Bpa in 2010. ICES recommends a closure of the fishery in 2009 and a recovery plan should be developed and implemented as a prerequisite to reopening the fishery. Short-term implications Outlook for 2009 It is not possible to partition estimates of total catch into landings and discards. The short-term implications are presented in terms of total catches. Basis: F(2008) = Fsq = F (05–07) = 0.60; R(2008) = 30.8 million; R(2009, Ricker1) = 118 million; SSB(2009) = 16.6; catches (2008) = 10.1; landings/catch (2007) = 0.44.

Rationale Catches (2009) Basis F(2009) SSB(2010) %SSB change2,3

Zero catch 0 F=0 0 29.6 78% High long-term yield 4.2 F(long-term yield) 0.2 25.4 53%

2.6 Fsq*0.2 0.12 27.0 63% 4.9 Fsq *0.4 0.24 24.6 48% 7.0 Fsq *0.6 0.36 22.5 36% 8.9 Fsq *0.8 0.48 20.7 25%

Status quo 10.7 Fsq *1 0.60 18.9 14% 12.2 Fsq *1.2 0.72 17.4 5%

Weights in ‘000 tonnes. Shaded scenarios are not considered consistent with the precautionary approach. 1 Recruitment derived from the stock–recruit relationship used by the assessment model. 2 SSB 2010 relative to SSB 2009. 3 TAC 2009 relative to TAC 2008 cannot be calculated since the forecast estimates total catch and not landings. Management considerations The strong 1999 year class has now diminished significantly and recent recruitments have been poor. The 2006 year class, recruited at age 1 in 2007, is the lowest recruitment estimate in the time-series. Because of the low recruitment it is not possible for the stock to reach Bpa in one year. A complete closure of the fishery in 2009 would bring SSB very close to Bpa in 2010. ICES recommends a recovery plan which should offer maximum protection to the haddock, recognizing that it is caught in a mixed fishery. It should include monitoring the trajectory of the stock, clearly stating specified reopening criteria, and monitoring the fishery when it is reopened. Special attention needs to be given to considering the sporadic nature of the haddock recruitment and how to manage periods of low recruitment interspersed with large, occasional pulses. In recent years around 50% of the total catch in weight has been discarded, so restricting landings alone may not achieve the necessary increase in SSB. Mainly 1- to 4-year-old haddock is discarded. Haddock in Division VIa are fully exploited from age group 3, and also reach full maturity at that age. Immature fish are subject to comparatively high fishing mortality, and comprise a large fraction of the discarded catch. High fishing mortality on immature haddock increases the susceptibility of the stock to overexploitation. The conflicting signals in the survey and the catch-at-age information indicate that since the mid-1990s there have been unaccounted catches. The recent implementation of stricter landings enforcement has potentially improved the quality of the landings data since 2006. Although the full effect of these measures cannot be assessed yet, the actual catches in 2006 and 2007 were within the bounds of error of the estimated catch. Several technical conservation measures have been introduced in the demersal fishery in Division VIa in recent years. These have affected selectivity for haddock because of switching between mesh categories. In addition, a number of decommissioning rounds and reallocation of effort from Division VIa into other ICES areas have reduced effort. However, the relationship between effort and mortality on haddock remains unclear. Management for haddock will be strongly linked to that for cod for which a recovery plan is currently in force.


Impacts of fisheries on the ecosystem Haddock is taken in mixed demersal fisheries and there are no impacts specific to the catching of haddock (see Section 5.3.2). Factors affecting the fisheries and the stock Regulations and their effects In recent years, effort of trawling with larger mesh sizes (120 mm+ traditional gadoid fishery in Division VIa) appears to have been substantially reduced, with fisheries moving into the Nephrops fishery in Division IVa (principally, the Fladen Ground). The main reason appears to be lack of quota and restrictive day allocations related to the cod recovery plan in Division VIa. In Scotland the ‘Conservation Credits Scheme’ was implemented from the beginning of February 2008 and essentially grants vessels their 2007 allocation of days (operated as hours at sea) in return for observance of measures to avoid cod catch. Adherence to the measures under this scheme is not mandatory and it is too early for ICES to comment on the success of the measures in aiding cod recovery and reducing mortality on haddock. Changes in fishing technology and fishing patterns Haddock in Division VIa are caught mainly by Scottish trawlers. There has been a general decline in the haddock fishery in Division VIa: both Irish and Scottish sources suggest that there is an increasing focus in the corresponding Division VIb (Rockall) fishery and the neighbouring Nephrops fishery in Division IVa. There has been a shift from twin trawls to single trawls, and an increase in the use of pair trawls and seines. This is very much driven by fuel costs and may have implications for catch rates and possibly discards. Scientific basis Data and methods The analytical age-based assessment is based on landings-at-age data, discard-at-age data, and indices from research vessel surveys. Due to uncertainties in landings prior to 2006, commercial catch numbers from 1995–2007 were not used in the assessment. The assessment model therefore estimates total catches from the fishery. Uncertainties in assessment and forecast This year’s forecast for haddock in Division VIa is based on an assessment principally driven by survey data since 1995. As is often observed for assessments based primarily on survey information, SSB and recruitment are better estimated than fishing mortality. The estimated fishing mortality has broad confidence intervals (between 0.3 and 0.8 in 2007). Unaccounted removals have been taken into account in the assessment. Changes in natural mortality are not thought to be the principal source of the estimated unallocated removals from the stock. Because commercial landings and discards observations are not included in the assessment from 1995 onwards the assessment model cannot respond to the changes in discard practices that have occurred in recent years. The assessment model therefore partitions total catch into landings and discards using commercial data up to 1995, but this assumption is not appropriate for the fishery in 2007 and subsequent years. The forecast is therefore presented in terms of total catch (landings and discards combined). A number of assumptions have been made about weights-at-age in the forecast to account for the slow-growing 1999 and 2000 year classes. Comparison with previous assessment and advice Last year’s assessment indicated that SSB would continue to decline as the 1999 year class moves out of the population and recent recruitment continues to be poor; the current assessment is consistent with this. Last year the advice was based on a large reduction in fishing mortality to maintain the stock above Bpa. SSB continued to decline in 2007 and ICES recommends the development of a management plan.


Source of information Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 15–21 May 2008 (ICES CM 2008/ACOM:08). Year ICES

Advice Single-Stock Exploitation Boundaries

Predicted catch

corresp. to advice

Predicted catch

corresp. to Single-Stock

Exploitation Boundaries

AgreedTAC1

Official Landings

ICES Landings

Discard Slip.

ICES Catch

1987 Reduce F towards Fmax 20.0 32.0 27 27.0 16.2 43.2 1988 No increase in F; TAC 25.0 35.0 21 21.1 10.2 31.3 1989 80% of F(87); TAC 15.0 35.0 24 16.7 3.2 19.9 1990 80% of F(88); TAC 14.0 24.0 13 10.1 5.4 15.5 1991 70% of effort (89) - 15.2 10 10.6 9.2 19.8 1992 70% of effort (89) - 12.5 7 11.42 9.42 20.82 1993 70% of effort (89) - 17.6 13 19.12 16.92 36.02 1994 30% reduction in effort - 16.0 9 14.22 11.22 25.42 1995 Significant reduction in

effort - 21.0 13 12.4 8.8 21.2


- 22.9 13 13.4 11.8 25.3


- 20.0 13 12.9 6.6 19.5

1998 No increase in F 20.83 25.7 14 14.4 5.7 20.1 1999 F reduced to Fpa 14.33 19.0 11 10.4 5.1 15.6 2000 Maintain F below Fpa <14.93 19.0 7 6.9 8.2 15.2 2001 Reduce F below Fpa <11.23 13.9 7 6.7 7.2 14.0 2002 Reduce F below Fpa <14.13 14.1 7 7.1 8.6 15.2 2003 No cod catches - 8.7 4.9 5.3 4.2 9.6 2004 4 Fpa 12.2 6.5 3.0 3.2 n/a n/a

2005 4 ¾* Fpa 7.6 7.6 3.2 3.1 n/a n/a

2006 4 0.7* Fpa 8.0 7.81 5.7 5.7 n/a n/a

2007 0.87* Fpa 7.2 7.2 3.7 3.7 n/a n/a

2008 SSB>Bpa in 2009

4.2 6.12

2009 No fishing and recovery plan

0

All weights in thousand tonnes. 1 TAC is set for Divisions VIa and VIb (plus Subdivision Vb1 and Subareas XII and XIV), combined with restrictions on the quantity that can be taken in Division VIa from 1990. 2 Adjusted for misreporting. 3 For Division VIa only. 4 Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits.


Figure 5.4.23.1 Haddock in Division VIa. TSA stock summaries from the final run (missing catch data from 1995

onwards). Estimates are plotted with approximate point-wise 95% confidence bounds. Dots indicate observed values for catch. The vertical line in each plot delineates the last year of the historical assessment (2007); estimates to the right of these lines are the TSA-based forecast.

0

10

20

30

40

50

60to

tal c

atch

(tho

usan

d t)

1980 1990 2000

0

10

20

30

40

50

60

land

ings

(tho

usan

d t)

1980 1990 2000

0

10

20

30

40

50

60

disc

ards

(tho

usan

d t)

1980 1990 2000

0

100

200

300

400

500

600

700

recr

uitm

ent a

t age

1 (m

illio

ns)

1980 1990 2000

0.0

0.5

1.0

1.5m

ean

fishi

ng m

orta

lity

(age

s 2-

6)

1980 1990 2000

0

20

40

60

80

100

120

spaw

ning

sto

ck b

iom

ass

(thou

sand

t)

1980 1990 2000

BpaBlim

Fpa

0

10

20

30

40

50

60to

tal c

atch

(tho

usan

d t)

1980 1990 2000

0

10

20

30

40

50

60

land

ings

(tho

usan

d t)

1980 1990 2000

0

10

20

30

40

50

60

disc

ards

(tho

usan

d t)

1980 1990 2000

0

100

200

300

400

500

600

700

recr

uitm

ent a

t age

1 (m

illio

ns)

1980 1990 2000

0.0

0.5

1.0

1.5m

ean

fishi

ng m

orta

lity

(age

s 2-

6)

1980 1990 2000

0

20

40

60

80

100

120

spaw

ning

sto

ck b

iom

ass

(thou

sand

t)

1980 1990 2000

BpaBlim

Fpa


Figure 5.4.23.2 Haddock in Division VIa (West of Scotland). Stock and recruitment, Yield and SSB per recruit, and

PA plot.

Stock - Recruitment

0

100

200

300

400

500

600

0 20 40 60 80 100 120

SSB in 1000 t

Rec

ruitm

ent (

age

1) in

m

illio

ns SSB-Rec.

Blim

Bpa


00.020.040.060.080.1

0.120.140.160.18

0 0.2 0.4 0.6 0.8 1 1.2 1.4


Yiel

d (d

ashe

d lin

e)

0

0.5

1

1.5

2

2.5

SSB

(lin

e)


0

20

40

60

80

100

120

0.0 0.2 0.4 0.6 0.8 1.0 1.2


SSB

in 1

000

t

F-SSB

2007

Fpa

Blim

Bpa


Figure 5.4.23.3 Haddock in Division Via. Comparison of current assessment with previous assessments. Dotted

horizontal lines indicate limit reference points, solid horizontal line indicates precautionary reference points.

Haddock in Division VIa (West of Scotland)

0

20

40

60

80

100

120

1990 1995 2000 2005

SSB ('000 tonnes)

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1990 1995 2000 2005


0

100

200

300

400

500

600

700

1990 1995 2000 2005


ICES

Adv

ice

2008

, Boo

k 5

159

Tab

le 5

.4.2

3.1

Had

dock

in D

ivis

ion

VIa

. Nom

inal

land

ings

(t),

as o

ffic

ially

repo

rted

to IC

ES a

nd e

stim

ated

by

the

WG

. C

ount

ry

1988

19

89

1990

19

91

1992

19

93

1994

19

95

1996

19

97

1998

19

99

2000

20

01

2002

20

03

2004

20

05

2006

1 20

071

Bel

gium

D

enm

ark

Faro

e Is

land

s Fr

ance

G

erm

any

Ir

elan

d N

orw

ay

Spai

n U

K (E

& W

)3 U

K (N

. Ire

) U

K (S

cot.)

U

K (t

otal

) N

ethe

rland

s

8 + - 3,

001 4

2,73

1 54 -

114 35

15

,151

9 + 13

1,33

51,2 4

2,17

1 74 -

235

19,

940

- + - 86

31,2

15

773 46

- 16

4 10

,964

9 + 1 76

11,2 1

710 12

- 13

7 8,

434

1 1 - 76

1 2 70

0 72 -

132

5,26

3

7 1 - 1,

132 9

911 40

- 15

5 10

,423

1 - - 75

3 19

746 7 -

254

7,42

1

+ 1 - 67

1 14

1,40

6 13 -

322

10,3

67

1 1 - 44

5 2 1,

399

161 -

448 ...

10

,790

3 - - 27

0 1 14

47

211 -

493 ...

10

,352

2 + - 39

41 1 1,

352 28

2 45

8 …

12,1

25

2 - - 78

8 2 10

54

18 4

315 ...

8,

630

1 - n/

a 28

2 1 67

7 70 9

199 …

5,

933

2 - n/

a 16

0 1 74

4 32 4

201 …

5,

886

+ - 15

1 + 67

2 30 4

237 …

5,

988

+ + 18

3 - 49

7 23 5

107 …

4,

582

- 4 17

3 19

4 4 93

…

2,

909 1

+ 27

3 1 15

2 21

47

42

…

2,02

5

1 29

1 7 52

6 17

44

4,94

1

2 14

5 0 75

2 16

2779

To

tal r

epor

ted

21,0

98

23,7

81

12,8

25

10,0

65

6,93

2 12

,678

9,

201

12,7

94

13,1

02

12,5

87

14,3

60

10,8

13

7,16

3 7,

030

7,08

2 5,

397

3,37

8 2,

561

5,73

7 3,

694

WG

est

imat

es

21,1

36

16,6

88

10,1

35

10,5

57

11,3

50

19,0

60

14,2

43

12,3

68

13,4

53

12,8

74

14,4

01

10,4

30

6,95

2 6,

731

7,09

7 5,

334

3,19

9 3,

148

5,72

3 3,

702

1 Prel

imin

ary.

2 Incl

udes

Div

isio

ns V

b(EC

) and

VIb

.

3 1989

–200

5 N

. Ire

land

incl

uded

with

Eng

land

and

Wal

es.

n/a

= N

ot a

vaila

ble.

W

G e

stim

ates

refe

r to

the

sum

-of-

prod

ucts

of l

andi

ngs a

nd w

eigh

ts-a

t-age

pro

vide

d to

the

WG

, rat

her t

han

the

estim

ated

rem

oval

s pro

duce

d in

the

final

ass

essm

ent.



Table 5.4.23.2 Haddock in Division VIa (West of Scotland). Stock summary time-series.

Year Recruitment SSB Catch1 Mean F Age 1 Ages 2–6 thousands tonnes tonnes

1978 74544 40497 22018 0.653 1979 155464 32375 26906 0.759 1980 487978 36872 29484 0.603 1981 67437 78854 34994 0.454 1982 70771 104246 35857 0.443 1983 46002 93835 35014 0.454 1984 319285 66706 43246 0.693 1985 73176 66873 37525 0.615 1986 59648 61249 23539 0.427 1987 245287 55962 43309 0.873 1988 20090 47353 30335 0.791 1989 17620 38399 20548 0.793 1990 95437 22304 13089 0.659 1991 128065 21800 20486 0.741 1992 181039 29716 18981 0.587 1993 178816 44869 33352 0.858 1994 64540 46087 24810 0.597 1995 231527 44276 27700 0.606 1996 124407 47433 32633 0.723 1997 154949 51453 36072 0.816 1998 170098 42995 36462 0.827 1999 33028 37416 26252 0.918 2000 503527 24396 34112 1.016 2001 192797 48512 28595 0.587 2002 115299 67919 22080 0.410 2003 145708 71319 34644 0.659 2004 58178 50217 21163 0.564 2005 42374 48285 23473 0.675 2006 112123 34509 18240 0.543 2007 6539 27949 12521 0.555 2008 30803 24191

Average 135695 48673 28248 0.663

1 TSA estimates of total catch.


5.4.24 Haddock in Division VIb (Rockall)

State of the stock

Spawning biomass in relation to precautionary limits




Comment




Based on the most recent estimates of SSB (in 2008) and fishing mortality (in 2007) ICES classifies the stock as having full reproductive capacity and it is harvested sustainably. Spawning biomass has increased in recent years as a result of the 2000 and 2001 year classes. SSB has been above Bpa since 2003. Fishing mortality has been above Fpa throughout the time-series but has declined since 2005 to below Fpa. Management objectives There are no management objectives currently in place for this stock. Reference points Type Value Technical basis


Bpa 9 000 t Bpa = Blim * 1.4. This is considered to be the minimum SSB required to have a high probability of maintaining SSB above Blim, taking into account the uncertainty of assessments.

Flim Not defined. Not defined due to uninformative stock recruitment data.


Fpa 0.4 This F is adopted by analogy with other haddock stocks as the F that provides a small probability that SSB will fall below Bpa in the long term.

Targets Fy Not defined. (unchanged since: 1998) Yield and spawning biomass per recruit F-reference points Fish Mort Yield/R SSB/R Ages 2–5 Average last 3 years 0.25 0.14 0.57 Fmax 0.45* 0.15 0.30 F0.1 0.21 0.14 0.67 Fmed 0.42 0.15 0.33 * Fmax is poorly defined due to a flat-topped Y/R curve. A candidate for a target reference point consistent with taking high long-term yields and achieving a low risk of depleting the productive potential of the stock may be around F0.1 (0.21, based on total catches including discards). Single-stock exploitation boundaries Exploitation boundaries in relation to high long-term yield, low risk of depletion of production potential and considering ecosystem effects Fishing mortality around F0.1 (0.21) can be considered as a candidate target reference point consistent with taking high long-term yields and achieving a low risk of depleting the productive potential (< 5%). The present fishing mortality (0.25) is above the candidate reference point. Exploitation boundaries in relation to precautionary limits Fishing mortality should be less than Fpa, corresponding to total catches less than 9740 t in 2009. Landings should be less than 6470 t in 2009.


Conclusion on exploitation boundaries In the present situation with a stock that is well above Bpa and fishing mortality below Fpa there is little gain to the long-term yield by increasing fishing mortality above current levels. ICES therefore recommends to limit catches to 6490 t in 2009 and landings to 4330 t. Short-term implications Outlook for 2009 Basis: F(2008) = Fsq = F(04–07) =0.25; R = GM 91–05 =62.1 million; SSB(2008) =23.4; SSB(2009) =21.8; total catch (2008) =5.8; landings(2008) =4.1.

Rationale Total Catch (2009)

Landings (2009)

Discards (2009)

Basis F (2009)

SSB (2010)

% SSB change1)

% TAC change1)

Zero catch 0.00 0.00 0.00 F=0 0 31.68 31% -100 High long-term yield 5.61 3.74 1.81 F(0.1) 0.21 26.19 17% -46 1.42 0.95 0.47 Fsq *0.2 0.05 30.21 28% -86 4.07 2.72 1.35 Fsq *0.6 0.15 27.46 21% -61 Status quo 6.49 4.33 2.16 Fsq 0.25 24.98 13% -37 8.71 5.79 2.92 Fsq *1.4 0.35 22.72 4% -16 Fpa 9.74 6.47 3.27 Fsq *1.6=Fpa 0.40 21.68 -1% -6 10.73 7.12 3.61 Fsq *1.8 0.45 20.68 -5% 3 11.68 7.75 3.94 Fsq *2.0 0.50 19.73 -10% 12 Units: ‘000 tonnes. Shaded scenarios are not considered consistent with the precautionary approach. 1) SSB 2010 relative to SSB 2009. Total catches have been partitioned into landings and discards using the average ratio of discards to catches over the period 1999 to 2007. Management considerations The TAC only applies to catches in the EU zone. The TAC should apply to all areas and countries having fisheries for this stock. Part of Division VIb has since 1999 been in international waters where non-EU vessels are not subject to TAC. This allows for an unregulated fishery in the Rockall area. In addition, misreporting and discarding can lead to removals that exceed the TAC. There is a need for an internationally agreed management plan. Such a plan should involve extensive collaboration between stakeholders, scientists, and management authorities in both the design and the monitoring of conservation measures. Management measures in the haddock fishery could be a combined application of TAC and limits of fishing efforts and should include effective control and enforcement measures. The forecast predicts future catches disaggregated into landing and discard components. The discard ratio is around 50% in 1991–2007 and 38% in the recent period (1999–2007). The discard ratio was around 40% in 2007. Some countries land the whole catch while others discard part of the catch. For countries which discard part of the catch the discard ratio reaches 60–75% by weight. It would be beneficial to develop and introduce into fisheries practice measures aimed at preventing discards of haddock. Elaboration of such measures complies with recommendations under the UNGA Resolution 61/105 that urges States to take action to reduce or eliminate fish discards (UNGA Resolution 61/105, 2007, Chapter VIII, item 60). Haddock is taken in a mixed fishery. Some of the fisheries include substantial catches of blue whiting and non-assessed species such as grey gurnard. Factors affecting the fisheries and the stock The effects of regulations Following the NEAFC agreement in March 2001, an area of the NEAFC zone around Rockall was closed to fishing. In spring 2002, part of the shallow water in the EU component was also closed to trawling. The main goal of the ban was to protect young haddock distributed in shallow water. Effort in the rectangle containing the closure declined when the closure came into effect. There was also a decline in UK effort across the bank as a whole at this time, but an increase of effort in other areas of Division VIb. Spawning biomass has increased since 2003, the fishing mortality has decreased


since 2004. In 2005–2007, mortality reached the lowest estimates for the recent 15 years. The fishing mortality has decreased for small individuals (age 1 and 2) since 2001. However, it is difficult to determine to what extent this may be contributed to the efforts made to protect juveniles in the closed area. Scientific basis Data and methods The assessment is based on catch numbers-at-age and one survey index (Scottish Groundfish Survey). Discarding occurs in part of the fishery and has been estimated and used in the assessment. Uncertainties in assessment and forecast The survey covers only part of the currently known distribution area of haddock. The survey index may thus in part reflect changes in the distributional pattern, and not only in stock dynamics. An annual survey covering the whole of the distributional area may improve the assessment of the stock status. There is an urgent requirement for well-designed scientific monitoring programmes capable of delivering accurate data on trends in abundance and composition of the fish fauna throughout the area, in a form that can support the development and implementation of a management plan for Rockall Bank. Comparison with previous assessment and advice The overall trends are similar to those obtained last year. Estimates of fishing mortality have been revised upwards and SSB has been revised downwards, both by around 12% for recent years. The basis for the advice is the same as last year. Sources of information Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 15–21 May 2008 (ICES CM 2008/ACOM:08).


Year ICES


Predicted catch

corresp. to advice

Predicted catch


Agreed TAC1

Official Landings

ICES Landings

1987 Precautionary TAC 10.0 8.0 8.4 1988 Precautionary TAC 10.0 7.6 7.9 1989 Status quo F; TAC 18.0 6.6 6.7 1990 Precautionary TAC 5.5 8.2 3.9 1991 Precautionary TAC 5.5 5.9 5.7 1992 Precautionary TAC 3.8 4.5 5.3 1993 80% of F(91) 3.0 4.1 4.8 1994 If required, precautionary

TAC - 3.7 5.72

1995 No long-term gain in increasing F

5.13 5.5 5.6


6.93 6.8 7.1

1997 No advice given 4.93 5.2 5.2 1998 No increase in F 4.9 5.1 4.5 1999 Reduce F below Fpa 3.8 6.0 5.1 2000 Reduce F below Fpa < 3.5 5.74 5.35 2001 Reduce F below Fpa < 2.7 2.34 2.05

2002 Reduce F below 0.2 <1.3 3.0 3.3 2003 Lowest possible F - 6.1 6.2 2004 6 Lowest possible

catch - 0.702* 6.3 6.4

2005 6 Lowest possible catch

0.702* 5.2 5.2

2006 6 Lowest possible catch

0.597* 3.1 2.7

2007 Reduce F below Fpa 6 <7.11 4.615* 3.3 3.3

2008 Keep F below Fpa 6 <10.67 6.916* 2009 No long-term gains in

increasing F 6 <4.38

Weights in ‘000 t. 1 TAC is set for Divisions VIa and VIb (plus Subdivision Vb1 and Subareas XII and XIV), combined with restrictions on

the quantity that can be taken in VIa from 1990. 2 Including misreporting. 3 Landings at status quo F. 4 Incomplete data. 5 Russian data adjusted to exclude fish below MLS of 30 cm. 6 Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries

protecting stocks outside safe biological limits. 7 This corresponds to catch (= landings + discards). 8 This corresponds to landings. *Agreed EU TAC for Division VIb and Subareas XII and XIV.


Figure 5.4.24.1 Haddock in Division VIb (Rockall). Total landings and discards, fishing mortality, recruitment, and

SSB.

Total Catch & Landings

02468

101214161820

1991 1993 1995 1997 1999 2001 2003 2005 2007

Land

ings

in 1

000

t

Fishing Mortality

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1991 1993 1995 1997 1999 2001 2003 2005 2007

F(ag

es 2

-5)

FFpa

Recruitment (age 1)

0

20

40

60

80

100

120

140

1991 1993 1995 1997 1999 2001 2003 2005 2007

Rec

ruitm

ent i

n m

illio

ns


0

5

10

15

20

25

30

35

1991 1993 1995 1997 1999 2001 2003 2005 2007

SSB

in 1

000

t

SSBBlimBpa

02000

40006000

800010000

1200014000

1600018000

2000022000

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

Tonn

es

Discards

Landings


Figure 5.4.24.2 Haddock in Division VIb (Rockall). Stock and recruitment, yield (Landings+Discards), and SSB

per recruit.

Stock - Recruitment

0

20

40

60

80

100

120

140

0 5 10 15 20 25 30 35

SSB in 1000 t

Recr

uitm

ent (

age

1) in

m

illio

ns SSB-Rec.

Blim

Bpa


00.020.04

0.060.080.1

0.12

0.140.16

0 0.1 0.2 0.3 0.4 0.5 0.6


Yie

ld (d

ashe

d lin

e)

0

0.5

1

1.5

2

2.5

SSB

(lin

e)


0

5

10

15

20

25

30

35

0.0 0.2 0.4 0.6 0.8 1.0 1.2


SSB

in 1

000

t F-SSB2007FpaBlimBpa


Figure 5.4.24.3 Haddock in Division VIb (Rockall). Comparison of current assessment with previous assessments.

Haddock in Division VIb (Rockall)

0

5

10

15

20

25

30

35

1990 1995 2000 2005

SSB ('000 tonnes)

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1990 1995 2000 2005


0

20

40

60

80

100

120

140

1990 1995 2000 2005


ICES

Adv

ice

2008

, Boo

k 5

168

Tab

le 5

.4.2

4.1

Nom

inal

cat

ch (t

onne

s) o

f had

dock

in D

ivis

ion

VIb

, 198

9–20

05, a

s off

icia

lly re

porte

d to

ICES

. . C

OU

NT

RY

19

89

1990

19

91

1992

19

93

1994

19

95

1996

19

97

1998

19

99

2000

20

01

2002

20

03

2004

20

05

2006

20

071

Faro

e Is

land

s -

- -

- -

- -

- -

- -

n/a

n/a

2 2

Fran

ce

…2

…2

…2

…2

…2

…2

…2

- -

-*

5 2*

+ 1

1

Ger

man

y, F

ed.

Rep

. 1

- -

- -

- -

- -

- -

- -

Icel

and

- -

- -

- -

- -

+ -

167

- -

-

Irel

and

- 62

0 64

0 57

1 69

2 95

6 67

7 74

7 89

5 70

4 1,

021

824

357

206

169

195

105

41

336

Nor

way

47

38

69

47

68

75

29

24

24

40

61

15

2 70

49

60

32

33

12

3 84

Portu

gal

- -

- -

- -

- -

- 4

- -

-

Rus

sian

Fed

erat

ion

- -

- -

- -

- -

- -

458

2,15

4 63

0 1,

630

4,23

7 5,

844

4,70

8 2,

154

1,28

2

Spai

n 33

7 17

8 18

7 51

-

- 28

1

22

21

25

47

51

7 19

UK

(E, W

& N

I)

272

238

165

74

308

169

318

293

165

561

288

36

- -

56

UK

(Sco

tland

) 5,

986

7,13

9 4,

792

3,77

7 3,

045

2,53

5 4,

439

5,75

3 4,

114

3,76

8 3,

970

2,47

0 1,

205

1,14

53 1,

606

4113

3323

4403

1,64

33

Uni

ted

Kin

gdom

Tota

l 6,

643

8,21

3 5,

853

4,52

0 4,

113

3,73

5 5,

491

6,81

8 5,

220

5,09

8 5,

990

5,68

8 2,

315

3,03

7

6,14

8

6,30

6 5,

178

2,76

0 3,

348

Una

lloca

ted

catc

h 85

-

4,32

9 -1

98

800

671

1,99

8 -3

79

-543

-5

91

-599

-851

-357

-2

79

299

94

139

1 29

0 0

WG

est

imat

e 6,

728

3,88

4 5,

655

5,32

0 4,

784

5,73

3 5,

112

6,27

5 4,

629

4,49

9 5,

139

5,33

14

2,03

64 3,

3364

6.24

24

6,44

5 5,

179

3,05

0 3,

348

1 Prel

imin

ary.

2 In

clud

ed in

Div

isio

n V

Ia.

3 Incl

udes

UK

Eng

land

, Wal

es, a

nd N

.I. la

ndin

gs.

4 incl

udes

the

tota

l Rus

sian

cat

ch.

5 no

n-of

ficia

l. n/

a =

not a

vaila

ble.

.



Table 5.4.24.2 Haddock in Division VIb (Rockall).

Year Recruitment SSB Catches Landings Discards Mean F total

Age 1 Ages 2–5 thousands tonnes tonnes tonnes tonnes

1991 110170 15895 18884 5656 13228 0.701992 109866 19375 17192 5321 11871 0.791993 122774 20221 14634 4781 9853 0.601994 68853 24599 16755 5732 11023 0.571995 61532 29598 14756 5587 9168 0.591996 62561 25460 16428 7072 9356 0.561997 71826 21874 11061 5167 5894 0.401998 72687 20836 15848 4986 10862 0.581999 49032 16570 16418 5356 11062 0.852000 28345 11789 12053 5444 6609 1.082001 79528 6845 3658 2123 1535 0.412002 109742 7192 7270 3117 4152 0.462003 52416 13866 11490 5969 5521 0.642004 20113 17724 7321 6437 883 0.622005 29818 18062 5693 5191 505 0.312006 70138 16866 3142 2756 386 0.172007 28530 17497 5580 3348 2242 0.262008 62081 23367

Average 67525 17898 11658 4944 6715 0.56


5.4.25 Whiting in Division VIa (West of Scotland)

Single-stock exploitation boundaries The new landing and survey data available for this stock do not change the perception of the stock and do not give reason to change the advice from 2007. The advice for the fishery in 2009 is therefore the same as the advice given in 2007 for the 2008 fishery: “Given that SSB is estimated at the lowest observed level and total mortality at the highest level over the time period, catches [...] should be reduced to the lowest possible level.” This advice will be updated in 2009. Source of information Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 15-21 May 2008 (ICES CM 2008/ACOM:08). Year ICES


Predicted catch

corresp. to advice

Catch corresponding

to single-stock

boundaries

AgreedTAC1

Official Landings

ICES Landings

Discardsslip

ICES catch

1987 No increase in F 15.0 16.4 12.4 11.5 6.9 18.4 1988 No increase in F; TAC 15.0 16.4 11.9 11.4 11.8 23.1 1989 No increase in F; TAC 13.0 16.4 7.7 7.5 4.1 11.6 1990 No increase in F; TAC 11.0 11.0 6.0 5.6 4.4 10.0 1991 70% of effort (89) - 9.0 6.9 6.7 5.3 12.0 1992 70% of effort (89) - 7.5 6.0 6.0 9.4 15.4

1993 70% of effort (89) - 8.7 6.8 6.9 8.5 15.4

1994 30% reduction in effort

- 6.8 5.8 5.9 8.9 14.8


- 6.8 6.3 6.1 7.6 13.7


- 10.0 6.6 7.2 6.9 14.1


- 13.0 6.2 6.3 4.9 11.2

1998 No increase in F 6.5 9.0 4.7 4.6 5.8 10.5 1999 Reduce F below Fpa 4.3 6.3 4.7 4.6 3.1 7.7 2000 Reduce F below Fpa <4.3 4.3 3.2 3.0 6.7 9.7 2001 Reduce F below Fpa <4.2 4.0 2.5 2.4 2.4 4.9 2002 SSB>Bpa in short term <2.0 3.5 1.7 1.7 2.1 3.8 2003 No cod catches - 2.0 1.3 1.3 1.6 2.9 2004 2 SSB>Bpa in

the short term 2 <2.1 1.6 0.8 0.8 2.6 3.4

2005 Exploitation not allowed to increase

<1.6 1.6 0.29 0.3 0.9 1.2

2006 Lowest possible level 0 1.36 0.38 0.4 0.9 1.3

2007 Lowest possible level 0 1.02 0.48 0.5 0.3 0.8

2008 Lowest possible level 0 0.765 2009 Same advice as last

year 0

Weights in ‘000 t. n/a = not available. 1TAC is set for Divisions VIa and VIb combined. 2Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits.

ICES

Adv

ice

2008

, Boo

k 5

171

Tab

le 5

.4.2

5.1

Whi

ting

in D

ivis

ion

VIa

. Nom

inal

cat

ch (t

), 19

89–2

007,

as o

ffic

ially

repo

rted

to IC

ES.

Cou

ntry

19

89

1990

19

91

1992

19

93

1994

19

95

1996

19

97

1998

19

99

2000

20

01

2002

20

03

2004

20

05

2006

20

07*

Bel

gium

1

- +

- +

+ +

- 1

1 +

- -

- -

+ -

- -

Den

mar

k 1

+ 3

1 1

+ +

+ +

- -

- -

- +

+ -

- -

Faro

e Is

land

s -

- -

- -

- -

- -

- -

- -

- -

- -

- +

Fran

ce

1991

180

3521

105

149

191

362

202

108

82

300

48

52

21

11

6 9

7 1

Ger

man

y +

+ +

1 1

+ -

+ -

- +

- -

- -

- -

+ 1

Irel

and

1315

97

7 12

00

1377

11

92

1213

14

48

1182

97

7 95

2 1,

121

793

764

577

568

356

172

196

56

Net

herla

nds

- -

- -

- -

- -

- -

- -

- -

- -

- -

-

Spai

n -

- -

- -

- 1

- 1

2 +

- 2

- -

- -

- -

UK

(E, W

& N

I)

44

50

218

196

184

233

204

237

453

251

210

104

71

73

35

13

5 2

…

UK

(Sco

t.)

6109

48

19

5135

43

30

5224

41

49

4263

50

21

4638

33

69

3046

22

58

1654

10

64

751

444

103

178

…

UK

(tot

al)

424

Tota

l lan

ding

s 76

69

6026

69

08

6010

67

51

5786

62

78

6642

61

78

4657

46

77

3203

25

43

1735

13

65

819

289

383

482

* Pre

limin

ary.

1 In

clud

es D

ivis

ions

Vb

(EC

) and

VIb

.

1989

–200

6 N

. Ire

land

incl

uded

with

Eng

land

and

Wal

es.

n/a

= N

ot a

vaila

ble.



5.4.26 Whiting in Division VIb (Rockall)

State of the stock Landings of whiting from Division VIb are negligible. No assessment has been carried out on this stock. Source of information Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 15-21 May 2008 (ICES CM 2008/ACOM:08).


5.4.27 Saithe in Subarea VI (West of Scotland and Rockall) This stock has now been combined with saithe in Subarea IV (North Sea), Division IIIa (Skagerrak), and Subarea VI (West of Scotland and Rockall) and can be found in Book 6 North Sea, Section 6.4.12.


5.4.28 Megrim in Subarea VI (West of Scotland and Rockall)

The new landings, cpue, and survey data available for this stock do not change the perception of the stock and do not give reason to change the advice from 2007. The advice on this stock for the fishery in 2009 is therefore the same as the advice given in 2007 for the 2008 fishery: “Catches […] should be based on the recent average (2004–2006), about 1400 t. This includes landings in Division VIa and VIb and unallocated landings in Subarea IV”. In addition ICES offers the following consideration: Scientific surveys show that a significant population of megrim exists in the northern part of Division IVa and landings are reported from this area. However, this stock component is not considered by any ICES expert group. Recent surveys aimed at providing a scientific basis for anglerfish management, could potentially be used for the assessment of megrim stocks in Subarea VI and Division IVa. Area misreporting between IVa and VI still appears to be a problem due to the association of megrim with anglerfish catches. This advice will be updated in 2009. Source of information Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 15–21 May 2008 (ICES CM 2008/ACOM:08).


Year ICES



Predicted catch corresponding to single-stock boundaries

Agreed TAC1

Official Landings2

ICES Landings3

1987 Not assessed - 4.4 3.9 - 1988 Not assessed - 4.84 4.5 - 1989 Not assessed - 4.84 2.7 - 1990 Not assessed - 4.84 2.7 3.7 1991 No advice - 4.84 3.2 3.7 1992 No advice - 4.84 3.2 4.8 1993 No long-term gain in

increased F - 4.84 3.0 4.3

1994 No long-term gain in increased F

- 4.84 3.0 4.3

1995 No advice - 4.84 3.3 4.6 1996 No advice - 4.84 2.9 5.3 1997 No advice - 4.84 2.8 4.6 1998 Adequate catch controls - 4.84 2.7 4.2 1999 Maintain current TAC 4.84 4.84 2.5 3.8 2000 Maintain current TAC 4.84 4.84 2.4 3.6 2001 Maintain current TAC 4.84 4.36 2.4 3.3 2002 Maintain current TAC 4.36 4.36 1.6 2.3 2003 Maintain current TAC 4.36 4.36 1.7 2.3 2004 4 Reduce TAC to

recent landings 3.60 3.60 1.4 1.8

2005 4 Reduce TAC to recent landings

2.3 2.88 0.9 n/a

2006 4 Reduce TAC to recent landings

2.3 2.88 0.9 1.1

2007 Reduce TAC to recent landings

2.1 2.88 0.8 1.3

2008 Reduce TAC to recent landings

1.4 2.59

2009 Same advice as last year 1.4

Weights in ‘000 t. 1 Division Vb(EC) and Subareas VI, XII, and XIV. 2 Divisions VIa and VIb. 3 Landings in Divisions VIa and VIb and unallocated landings from Subarea IV. Landings in Vb (EC), XII, and XIV are negligible. 4 Single-stock boundaries and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits. n/a = not available.

ICES

Adv

ice

2008

, Boo

k 5

176

Tab

le 5

.4.2

8.1

Meg

rim in

Div

isio

n V

Ia: N

omin

al c

atch

(t) o

f meg

rim w

est o

f Sco

tland

and

Roc

kall,

as o

ffic

ially

repo

rted

to IC

ES a

nd W

G b

est

estim

ates

of l

andi

ngs.

C

ount

ry

1990

19

91

1992

19

93

1994

19

95

1996

19

97

1998

19

99

2000

20

01

2002

20

03

2004

20

05

2006

20

071

Bel

gium

0

1 0

0 1

0 0

0 0

0 0

0 0

0 0

0 0

D

enm

ark

0 0

0 0

0 0

0 0

0 0

0 0

0 0

0 0

0

Fran

ce

398

455

504

517

408

618

462

192

172

0 13

5 25

2 79

92

50

48

53

Irel

and

317

260

317

329

304

535

460

438

433

438

417

509

280

344

278

156

221

1912

Net

herla

nds

0 0

0 0

0 0

0 1

0 0

0 0

0 0

0 0

0

Spai

n 91

48

25

7

1 24

22

87

11

1 83

98

92

89

98

45

69

52

UK

- En

g+W

ales

+N.Ir

l. 25

16

7 39

2 29

8 32

7 32

2 15

6 12

3 65

42

20

7

14

13

17

10

0

UK

– S

cotla

nd

1093

12

23

887

896

866

952

944

954

841

831

754

770

643

558

469

269

336

6322

UK

Off

ical

Tot

al

1924

21

54

2125

20

47

1907

24

51

2044

17

95

1622

13

94

1424

16

30

1105

11

05

859

552

662

823

U

nallo

cate

d 28

6 27

8 42

4 67

4 78

6 10

47

2010

14

77

1083

12

54

823

843

723

537

469

9 21

3 n/

a

As u

sed

by W

G

2210

24

32

2549

27

21

2693

34

98

4054

32

72

2705

26

48

2247

24

73

1828

16

42

1328

56

1 87

5 13

01

A

rea-

mis

repo

rted

land

ings

33

9 33

8 46

6 73

5 87

1 11

26

2062

15

56

1156

10

66

868

829

731

544

421

n/a

212

478

1 Pr

ovis

iona

l est

imat

e.

2 D

ata

supp

lied

by n

atio

nal s

cien

tists

at W

GN

SDS.


ICES Book 2008, Book 5 177

5.4.29 Anglerfish (Lophius piscatorius and L. budegassa) in Division IIIa (Kattegat and Skagerrak), Subarea IV (North Sea), and Subarea VI (West of Scotland and Rockall)

The new data available for this stock do not change the perception of the stock and do not give reason to change the advice from 2007. The advice for the fishery in 2009 is therefore the same as the advice given in 2007 for the 2008 fishery: “The effort in fisheries that catch anglerfish should not be allowed to increase and the fishery must be accompanied by mandatory programmes to collect catch and effort data on both target and bycatch fish.” In addition, ICES offers the following considerations: Following ICES suggestions in 2005 a number of initiatives were instigated covering anglerfish in Division IVa and Subarea VI:

• dedicated Scottish and Irish scientific anglerfish surveys which are coordinated to involve the use of both research vessels and commercial fishing vessels;

• a Scottish tallybook scheme (linked to a longer time-series of personal diaries); • increased observer coverage (short-term initiative in 2006).

Data are currently being gathered, with improvements to both industry-related data and surveys covering Subarea VI and part of the North Sea. There are currently 3 years of survey-derived absolute abundance estimates and 2 complete years of Scottish tallybook data providing commercial catch data. ICES will provide updated advice in 2009. Source of information Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 15–21 May 2008 (ICES CM 2008/ACOM:08).


Subarea IV – North Sea Year ICES


Predicted catch

corresp. to advice

Predicted catch


Agreed TAC

Official landings

ICES Landings

1990 Not assessed - - - - 10.6 9.5 1991 Not assessed - - - - 11.8 10.6 1992 Not assessed - - - - 13.3 11.7 1993 Not assessed - - - - 15.5 13.1 1994 Not assessed - - - - 18.2 15.4 1995 Not assessed - - - - 20.9 15.8 1996 Not assessed - - - - 27.3 16.2 1997 Not assessed - - - - 25.8 18.2 1998 Not assessed - - - 22.1 19.0 14.0 1999 Not assessed - - - 22.1 14.9 11.7 2000 40% reduction in catches - <9.7 - 17.66 14.0 11.6 2001 2/3 of the catches in 1973–

1990 - 5.7 - 14.13 14.7 12.7

2002 2/3 of the catches in 1973–1990

- 5.7 - 10.50 12.3 10.3

2003 Reduce F below Fpa - <6.72 - 7.0 9.4 8.3

2004 1 Reduce F below Fpa

<8.8 7.0 9.8 9.0

2005 1 No effort increase

- 10.31 9.1 n.a.


- 10.31 11.0 n.a.


- 11.34 11.3 n.a.


- 11.34

2009 Same advice as last year No effort increase

-

Weights in ‘000 t. 1Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits. 2Advice for Division IIIa, Subarea IV, and Division VIa combined. n.a. = not available.


Subarea VI – West of Scotland and Rockall Year ICES

Advice Single-stock

exploitation boundaries

Predicted catch

corresp. to advice

Predicted catch


Agreed TAC1

Official landings

ICES landings2

1987 Not assessed - 7.8 5.2 5.6 1988 Not assessed - 8.6 7.7 7.7 1989 Not assessed - 8.6 6.0 7.3 1990 Not assessed - 8.6 6.4 6.6 1991 No advice - 8.6 6.0 6.3 1992 No advice - 8.6 6.6 9.2 1993 No long-term gain in increased F - 8.6 6.2 10.1 1994 No long-term gain in increased F - 8.6 6.0 8.8 1995 A precautionary TAC not

exceeding recent catch levels - 8.6 7.2 12.3

1996 A precautionary TAC not exceeding recent catch levels

- 8.6 7.0 18.2

1997 Reduction in fishing effort - 8.6 6.2 13.7 1998 Reduction in fishing effort - 8.6 5.4 10.6 1999 Reduce fishing effort, effective

implementation of the TAC - 8.6 5.3 8.4

2000 40% reduction in catches <7.4 8.0 4.4 7.5 2001 2/3 of the catches in 1973–1990 4.3 6.4 4.0 5.9 2002 2/3 of the catches in 1973–1990 4.3 4.8 3.0 4.8 2003 Reduce F below Fpa <6.73 3.18 3.1 4.1 2004 4 Reduce F

below Fpa 4 3.18 3.1 3.3

2005 No effort

increase - 4.69 4.0 n.a.

2006 No effort increase

- 4.69 3.7 n.a.


- 5.15 4.3 n.a.


- 5.15

2009 Same advice as last year No effort increase

-

Weights in ‘000 t. 1Division Vb(EC) and Subareas VI, XII, and XIV. 2Division VIa only. 3Advice for Division IIIa, Subarea IV, and Subarea VIa combined. 4Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits. n.a. = not available.


Division IIIa, Subarea IV, and Subarea VI combined Year ICES


Predicted catch

corresp. to advice

Predicted catch


Agreed TAC1

Official landings

ICES landings2

2003 Reduce F below Fpa <6.7 10.2 12.5 n/a 2004 2 Reduce F below Fpa

2 <8.8 10.2 12.9 n/a 2005 No effort increase 2 - 15.0 13.1 n/a 2006 No effort increase 2 - 15.0 14.7 n/a 2007 No effort increase 2 - 16.5 15.6 2008 No effort increase 2 - 16.5 2009 Same advice as last year No effort increase 2 -

Weights in ‘000 t. 1Areas IV, IIa (EC) and Vb(EC), VI, XII, and XIV. 2 Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits. n/a = not available.


Table 5.4.29.1 Anglerfish in Division IIIa and Subareas IV and VI. Officially reported landings by ICES area.

IIIa IVa IVb IVc VIa VIb Total 1973 140 2085 575 41 9221 127 12189 1974 202 2737 1171 39 3217 435 7801 1975 291 2887 1864 59 3122 76 8299 1976 641 3624 1252 49 3383 72 9021 1977 643 3264 1278 54 3457 78 8774 1978 509 3111 1260 72 3117 103 8172 1979 687 2972 1578 112 2745 29 8123 1980 652 3450 1374 175 2634 200 8485 1981 549 2472 752 132 1387 331 5623 1982 529 2214 654 99 3154 454 7104 1983 506 2465 1540 181 3417 433 8542 1984 568 3874 1803 188 3935 707 11075 1985 578 4569 1798 77 4043 1013 12078 1986 524 5594 1762 47 3090 1326 12343 1987 589 7705 1768 66 3955 1294 15377 1988 347 7737 2061 95 6003 1730 17973 1989 334 7868 2121 86 5729 313 16451 1990 570 8387 2177 34 5615 822 17605 1991 595 9235 2522 26 5061 923 18362 1992 938 10209 3053 39 5479 1089 20807 1993 843 12309 3144 66 5553 681 22596 1994 811 14505 3445 210 5273 777 25021 1995 823 17891 2627 402 6354 830 28927 1996 702 25176 1847 304 6408 602 35039 1997 776 23425 2172 160 5330 899 32762 1998 626 16857 2088 78 4506 900 25055 1999 660 13326 1517 24 4284 1401 21212 2000 602 12338 1617 31 3311 1074 18973 2001 621 12861 1832 21 2660 1309 19304 2002 667 11048 1244 21 2280 718 15978 2003 478 8523 847 20 2493 643 13004 2004 519 8987 851 15 2453 671 13496 2005 458 8424 688 5 3019 958 13552 2006 423 10338 685 3 2785 916 15150 2007 426 10608 684 3 3178 1103 16002 Min 140 2085 575 3 1387 29 5623 Max 938 25176 3445 402 9221 1730 35039

Average 566 8659 1647 87 4047 715 15722

ICES

Adv

ice

2008

, Boo

k 5

182

Tab

le 5

.4.2

9.2.

A

ngle

rfis

h in

Sub

area

VI.

Nom

inal

land

ings

(t) b

y ar

ea a

nd c

ount

ry a

s off

icia

lly re

porte

d to

ICES

and

est

imat

ed b

y IC

ES.

1991

19

92

1993

19

94

1995

19

96

1997

19

98

1999

20

00

2001

20

02

2003

20

04

2005

20

06

2007

* V

Ia (W

est o

f Sco

tland

) B

elgi

um

3 2

9 6

5 -

5 2

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+ +

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enm

ark

1 3

4 5

10

4 1

2 1

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. +

+ -

- -

Faro

e Is

. -

- -

- -

- -

- -

- -

- -

2 2

3 2

Fran

ce

1,91

0 2,

308

2,46

7 2,

382

2,64

8 2,

899

2,05

8 1,

634

1,81

4 1,

132

943

739

1,21

2 1,

191

1,39

2 1,

314

1,59

9 G

erm

any

1 2

60

67

77

35

72

137

50

39

11

3 27

39

39

1

- Ir

elan

d 25

0 40

3 42

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ethe

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1

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orw

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6 14

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+ 1

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n 7

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33

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53

82

70

101

196

110

82

76

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K(E

,W&

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27

0 35

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44

40

32

31

30

20

24

…

U

K(S

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119

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974

…

UK

(tot

al)

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479

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408

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2,66

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453

3,01

9 2,

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068

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sed

by IC

ES

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117

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66

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56

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36

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1

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kall)

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toni

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e Is

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43

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36

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(E,W

&N

I)

99

173

76

50

105

144

247

188

111

272

197

133

133

54

93

46

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(Sco

t) 20

1 22

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2 28

1 19

9 68

15

6 18

9 34

4 37

4 36

7 31

7 16

0 29

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280

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816

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96

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9,47

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9 4,

833

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183

* Pr

elim

inar

y. 1 In

clud

ed in

VIa

/VIb

.


ICES

Boo

k 20

08, B

ook

5

183

Tab

le 5

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9.3.

A

ngle

rfis

h in

Sub

area

IV (N

orth

Sea

). N

omin

al la

ndin

gs (t

) by

area

and

cou

ntry

as o

ffic

ially

repo

rted

to IC

ES a

nd e

stim

ated

by

ICES

.

19

91

1992

19

93

1994

19

95

1996

19

97

1998

19

99

2000

20

01

2002

20

03

2004

20

05

2006

20

07*

IVa

Bel

gium

2

9 3

3 2

8 4

1 5

12

- 8

1 -

- -

- D

enm

ark

1,24

5 12

65

946

1,15

7 73

2 1,

239

1,15

5 1,

024

1,12

8 1,

087

1,28

9 1,

308

1,52

3 1,

538

1,37

9 1,

311

961

Faro

es

1 -

10

18

20

- 15

10

6

. 2

+ 3

11

22

2 +

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ce

124

151

69

28

18

7 7

3* 18

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8 9

8 8

8 4

7 11

G

erm

any

71

68

100

84

613

292

601

873

454

182

95

95

65

20

84

173

186

Net

herla

nds

23

44

78

38

13

25

12

- 15

12

3

8 9

38

13

14

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orw

ay

587

635

1,22

4 1,

318

657

821

672

954

1,21

9 1,

182

1,21

2 92

8 76

9 99

9 88

0 1,

005

831

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en

14

7 7

7 2

1 2

8 8

78

44

56

8 6

5 5

17

UK

(E, W

&N

I)

129

143

160

169

176

439

2,17

4 66

8 78

1 21

8 18

3 98

10

4 83

34

99

…

U

K (S

cotla

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7,03

9 7,

887

9,71

2 11

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15

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22

,344

18

,783

13

,319

9,

710

9,55

9 10

,024

8,

539

6,03

3 6,

284

6,00

3 7,

722

…

UK

(tot

al)

8,60

2 To

tal

9,23

5 10

,209

12

,309

14

,505

17

,891

25

,176

23

,425

16

,857

13

,326

12

,338

12

,861

11

,048

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523

8,98

7 8,

424

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38

10,6

08

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gium

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7 53

8 55

8 71

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9 28

7 33

6 37

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9 57

9 43

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0 26

0 20

7 13

8 17

7 D

enm

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345

421

347

350

295

225

334

432

368

260

251

255

191

274

237

276

173

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-

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ce

- 1

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- -*

…

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- -

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+ -

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Ger

man

y 4

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15

10

9

18

19

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9

17

11

11

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12

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237

223

141

141

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31

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318

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7 85

1 68

8 68

5 68

4 IV

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7

* Pr

elim

inar

y. 1 In

clud

es IV

b,c.

*

Prel

imin

ary.

1 Incl

udes

2 to

nnes

repo

rted

as S

ubar

ea IV

. 2 Incl

uded

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a.


ICES

Adv

ice

2008

, Boo

k 5

184

Tabl

e 5.

4.29

.4

Ang

lerf

ish

in D

ivis

ion

IIIa

(Ska

gerr

ak, K

atte

gat).

Nom

inal

land

ings

(t) b

y ar

ea a

nd c

ount

ry a

s off

icia

lly re

porte

d to

ICES

and

est

imat

ed b

y IC

ES.

19

91

1992

19

93

1994

19

95

1996

19

97

1998

19

99

2000

20

01

2002

20

03

2004

20

05

2006

20

07*

Bel

gium

15

48

34

21

35

-

- -

- -

- .

. .

- D

enm

ark

493

658

565

459

312

367

550

415

362

377

375

369

215

311

274

227

255

Ger

man

y -

- 1

- -

1 1

1 2

1 -

1 -

1 1

2 1

Net

herla

nds

- -

- -

- .

3 4

4 3

N

orw

ay

64

170

154

263

440

309

186

177

260

197

200

242

189

130

100

137

132

Swed

en

23

62

89

68

36

25

39

33

36

27

46

55

71

73

79

54

38

Tota

l 59

5 93

8 84

3 81

1 82

3 70

2 77

6 62

6 66

0 60

2 62

1 66

7 47

8 51

9 45

8 42

3 42

6 *P

relim

inar

y.



5.4.30 Herring in Division VIa (North)





Comment

Undefined Undefined Overfished NA Based on the most recent estimates of SSB and fishing mortality, ICES considers that the stock is currently fluctuating at a low level and is being exploited above Fmsy. Recruitment has been low since 1998, and the 2001 and 2002 year classes are very weak. Management objectives There are no explicit management objectives for this stock. However, a proposed management plan (see below) was evaluated by ICES in 2005 and found to be consistent with the precautionary approach. In 2005 ICES considered that a 15% constraint on variation did not greatly increase the risk. Greater constraint increased risk and reduced catches. This plan is still under discussion. F = 0.25 if SSB > 75 000 t Optional year-on-year TAC constraint. F = 0.2 if SSB < 75 000 t No constraint on TAC change. F = 0 if SSB falls below Blim. Reference points Type Value Technical basis

Blim 50 000 t Lowest reliable estimate of SSB Bpa Not defined Flim Not defined


Fpa Not defined Targets Fy Not defined Unchanged since 2004 Yield and spawning biomass per Recruit F-reference points:

Fish Mort Yield/R SSB/R Ages 3–7 Average last 3 years 0.27 0.04 0.14 Fmax N/A F0.1 0.18 0.04 0.19 Fmed 0.24 0.04 0.15

Management evaluations suggested an Fmsy of 0.25. Single-stock exploitation boundaries Exploitation boundaries in relation to the proposed management plan Fishing according to the proposed management plan would imply catches up to 13 000 tonnes. The proposed management plan was evaluated and found to be consistent with the precautionary approach. Exploitation boundaries in relation to high long-term yield, low risk of depletion of production potential and considering ecosystem effects Fishing mortality in the range of the target mortality of the proposed management plan is expected to give a high long-term yield and a low risk of stock depletion.


Exploitation boundaries in relation to precautionary limits Precautionary reference points for fishing mortality have not been defined for this stock. Any management measure should have a high probability of avoiding Blim. Conclusions on exploitation boundaries In the absence of exploitation boundaries in relation to precautionary limits ICES recommends to fish according to the proposed management plan. This corresponds to catches up to 13 000 tonnes. Short-term implications Outlook for 2009 Basis: F (2008) = F (TAC 2008) = 0.42; SSB (2009) = 60; landings (2008) = 27.2.

Rationale Catches (2009) Basis F(2009) SSB(2010) % TAC change 1)

Zero catch 0 F=0 F=0 96 -100%

Management plan 13 F=0.2 F=0.2 77 -52%

High long-term yield 16 F=0.25 F=0.25 73 -41%

Proportion of F 2007 19 F= F07*0.75 F=0.30 69 -31%

Proportion of F 2007 22 F= F07*0.88 F=0.35 65 -21%

F 2007 25 F=F07*1.00 F=0.40 61 -8%

Weights in ‘000 tonnes. Shaded scenarios are not considered consistent with the precautionary approach. 1) TAC 2009 relative to TAC 2008. Management considerations There has been considerable uncertainty in the amount of landings from this stock in the past. However, recent revisions to catch data have reduced some of this uncertainty. Enforcement has improved since 2005 and hence, recent catch figures are more accurate. In 2006 and 2007, the stock was more heavily exploited than it has been since 1999. This recent increased F is associated with various factors: increased enforcement; a reduction in area misreporting from Division IVa; a roll-over TAC advised for 2007 due to some uncertainty with the assessment; and low recruitment since 1998, with the 2001 and 2002 year classes being very weak. The ICES advice for 2008 was for a 56% TAC reduction. The TAC for 2008 was reduced by 20%. If the TAC is taken F will remain above the long-term target of F = 0.25. The stock identity of herring west of the British Isles was reviewed by the EU-funded project WESTHER. This identified Division VIaN as an area where catches comprise a mixture of fish from Divisions VIaN, VIaS, and VIIaN. Concerning the management plan for Division VIaN, ICES has advised that herring components should be managed separately to afford maximum protection. If there is an increasing catch on the mixed fishery in Division VIaN, this should be considered in the management of the Division VIaS component which is in a depleted state. In 2008 ICES will begin to evaluate management for this Division VIa(south) and VIIa(north). It will be a number of years before ICES can provide a fully operational integrated strategy for these units. In this context ICES recommends that the previously endorsed plans for Division VIaN should be continued. If the proposed management plan were to be implemented in 2008, the current low stock size would imply that the 15% TAC reduction limits would not apply. Impacts of fisheries on the ecosystems Herring are an important prey species in the ecosystem and also one of the dominant planktivorous fish. Herring fisheries tend to be clean with little bycatch of other fish. Scottish discard observer programmes since 1999 indicate that discarding of herring in these directed fisheries are at a low level. These discard observer programmes have recorded occasional catches of seals and zero catches of cetaceans. Herring fisheries rarely disturb the seabed.


Factors affecting the fisheries and the stock Changes in fishing technology and fishing patterns Historically, catches have been taken from this area by three fisheries:

i. A Scottish domestic pair trawl fleet and the Northern Irish fleet operated in shallower, coastal areas, principally fishing in the Minches and around the Island of Barra in the south; younger herring are found in these areas. This fleet has reduced in recent years.

ii. The Scottish single-boat trawl and purse-seine fleets, with refrigerated seawater tanks, targeting herring mostly in the northern North Sea, but also operating in the northern part of Division VIaN. This fleet now operates mostly with trawls, but many vessels can deploy either gear.

iii. An international freezer-trawler fishery has historically operated in deeper water near the shelf edge where older fish are distributed. These vessels are mainly registered in the Netherlands, Germany, France, and England, but most are Dutch owned.

In recent years the age structure of the catch of these last two fleets has become more similar. A stricter enforcement regime in the UK is responsible for the major decrease in area misreporting in 2006. Impacts of the environment on the fish stock Temperatures in this area have been increasing over the recent decades. There are indications that salinity is also increasing. It is considered that this may have implications for herring. It is known that similar environmental changes have affected the North Sea herring. There is evidence that there have been recent changes of the productivity of the Division VIaN stock. Herring are thought to be a source of food for seals. A recent study of seal diets off western Scotland revealed that grey seals may be an important predator for herring in this area. The numbers of seals in Division VIaN is thought to have increased over the last decades. The seal consumption of herring is estimated with great uncertainty and the impact of increased predation is not known, but there is a possibility that seal predation could influence natural mortality. Scientific basis Data and methods Analytic assessment using catch data and data from one acoustic survey. The acoustic survey used to tune the assessment has been re-evaluated and found to provide a useful, but noisy signal for tuning the assessment. Misreporting has decreased since 2006 and the quality of the catch data has improved. Uncertainties in assessment and forecast The assessment is considered to be noisy, but unbiased. Medium-term evaluations of the management plan have been carried out assuming the same level of noise as seen in the assessment. In 2007 there was conflicting information on recent recruitment between the catch and the survey data. However, there is no basis for concluding which source of data is more reliable; the catch is sparsely and partially sampled and the survey in 2007 appeared to have some sampling problems. Comparison with previous assessment and advice This year’s assessment is in agreement with last year’s, with F and SSB estimated within 5% of 2007 values. The advice for a major reduction in catch is in line with last year’s advice. Source of information Report of the Herring Assessment Working Group for the Area South of 62°N, 11–19 March 2008 (ICES CM 2008/ACOM:02).


Year ICES Advice


Agreed TAC

Disc. slip.

ICES Catch1

1987 Reduce F to F0.1/status quo F 38–55 49.7 44 1988 TAC 46 49.8 36 1989 TAC 58 58 1.6 34 1990 TAC 61 75 1.3 45 1991 TAC 57 62 1.2 29 1992 TAC 62 62 0.2 29 1993 Catch at status quo F 54–58 62 0.8 32 1994 Catch at status quo F 50–60 62 0.7 24 1995 No specific advice 602 77 30 1996 No advice because of misreporting - 83.57 26 1997 Catch at status quo F 83.57 0.1 333 1998 Catch at status quo F 59 80.37 0.9 33 1999 Average catches, 1991–1996 28 68 30 2000 Average catches, 1991–1996 28 42 184 2001 Average catches, 1991–1999 30 36.36 244 2002 Average catches, 1991–1999 30 36.36 334 2003 Catch at status quo F 30 30 284 2004 F=0.30 41 30 0.1 254 2005 Catch at status quo F 30 30.1 144 2006 Catch at status quo F 34 34 27 2007 Status quo TAC advice 34 34 30 2008 F =0.2 (proposed management plan) 15 27.2 2009 F =0.2 (proposed management plan) 13

Weights in ‘000 t. 1) Adjusted for misreporting. 2) Catch at status quo F. 3) Revised in 1999. 4) Revised at in 2007.


Figure 5.4.30.1 Herring in Division VIa (N). Landings, fishing mortality, recruitment, and SSB.

Landings

0

50

100

150

200

250

1958 1968 1978 1988 1998

Land

ings

in 1

000

t

Fishing Mortality

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1958 1968 1978 1988 1998

F(ag

es 3

-6)

Recruitment (age 1)

0

2

4

6

8

10

12

1958 1968 1978 1988 1998

Rec

ruitm

ent i

n bi

llion

s


0

100

200

300

400

500

600

1958 1968 1978 1988 1998 2008

SSB

in 1

000

t

SSB

Blim


Figure 5.4.30.2 Herring in Division VIa (N). Stock and recruitment, yield, and precautionary approach.


00.0050.01

0.0150.02

0.0250.03

0.0350.04

0.0450.05

0 0.2 0.4 0.6 0.8 1


Yie

ld (d

ashe

d lin

e)

0

0.1

0.2

0.3

0.4

0.5

0.6

SSB

(lin

e)

Stock - Recruitment

0

2

4

6

8

10

12

0 100 200 300 400 500 600

SSB in 1000 t

Rec

ruitm

ent (

age

1) in

bi

llion

s

SSB-Rec.

Blim


0

100

200

300

400

500

600

0.0 0.2 0.4 0.6 0.8 1.0 1.2


SSB

in 1

000

t

F-SSB

2007

Blim


Herring in Division VIa (North)

0

50

100

150

200

250

300

350

1990 1995 2000 2005

SSB ('000 tonnes)

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

1990 1995 2000 2005


0

0.5

1

1.5

2

2.5

1990 1995 2000 2005

Bill

ions

Recruitment. Age: 1

Figure 5.4.30.3 Herring in Division VIa (N). Historical performance of the assessments. Note: assessments prior to 2001 not comparable with recent assessments.


Table 5.4.30.1 Herring in Division VIa (N). Catch in tonnes by country, 1983–2006. These figures do not in all cases correspond to the official statistics and cannot be used for management purposes.

Country 1984 1985 1986 1987 1988 1989 1990 1991 Denmark 96 Faroes 954 104 400 326 482 France 20 18 136 44 1342 1287 1168 Germany 5564 5937 2188 1711 1860 4290 7096 6450 Ireland 6000 6800 6740 8000 10000 8000 Netherlands 7729 5500 5160 5212 6131 5860 7693 7979 Norway 6669 4690 4799 4300 456 1607 3318 UK 37554 28065 25294 26810 26894 29874 38253 32628 Unallocated 16588 -502 37840 18038 5229 2123 2397 -10597 Discards 1550 1300 1180 Total 75154 43814 81699 63007 47354 53039 69959 50608 Area-Misreported -19142 -4672 -10935 -18647 -11763 -19013 -25266 -22079 WG Estimate 56012 39142 70764 44360 35591 34026 44693 28529 Source (WG) 1986 1987 1988 1989 1990 1991 1993 1993 Country 1992 1993 1994 1995 1996 1997 1998 1999 France 119 818 274 3672 2297 3093 1903 463 Germany 5640 4693 5087 3733 7836 8873 8253 6752 Ireland 7985 8236 7938 3548 9721 1875 11199 7915 Netherlands 8000 6132 6093 7808 9396 9873 8483 7244 Norway 2389 7447 8183 4840 6223 4962 5317 2695 UK 32730 32602 30676 42661 46639 44273 42302 36446 Unallocated -5485 -3753 -4287 -4541 -17753 -8015 -11748 -8155 Discards 200 700 62 90 Total 51578 56175 54664 61271 64359 64995 65799 61514 Area-Misreported -22593 -24397 -30234 -32146 -38254 -29766 -32446 -23623 WG Estimate 28985 31778 24430 29575 26105 35233* 33353 29736 Source (WG) 1994 1995 1996 1997 1997 1998 1999 2000 Country 2000 2001 2002 2003 2004 2005 2006 2007 France 870 760 1340 1370 625 613 701 703 Germany 4615 3944 3810 2935 1046 2691 3152 1749 Ireland 4841 4311 4239 3581 1894 2880 4352 5354 Netherlands 4647 4534 4612 3609 8232 5132 7008 8052 Norway UK 22816 21862 20604 16947 17706 17494 18284 17618 Unallocated 878 -7 Discards 123 772 163 Total 37789 35411 36283 28835 29854 31392 34230 33960 Area-Misreported -19467 -11132 -8735 -3581 -7218 -17263 -6884 -4344 WG Estimate 18322$ 24556$ 32914$ 28081$ 25021$ 14129$ 27346 29616 Source (WG) 2001 2002 2003 2004 2005 2006 2007 2008


Table 5.4.30.2 Herring in Division VIa (North).

Year Recruitment Age 1 SSB Landings Mean F thousands tonnes tonnes Ages 3-6

1958 2256921 217271 59669 0.307 1959 2223173 234603 65221 0.278 1960 655164 271870 63759 0.177 1961 1325163 271741 46353 0.120 1962 2400431 261348 58195 0.188 1963 2179409 286475 49030 0.168 1964 997559 332796 64234 0.143 1965 7967406 339966 68669 0.150 1966 1074624 451328 100619 0.180 1967 2515751 480596 90400 0.180 1968 4109954 454409 84614 0.138 1969 3001534 491623 107170 0.235 1970 3442450 455346 165930 0.352 1971 9580461 324469 207167 0.777 1972 2676797 450451 164756 0.362 1973 1075497 388709 210270 0.603 1974 1675595 206337 178160 0.953 1975 2119231 108805 114001 0.902 1976 618256 75191 93642 1.058 1977 629396 53814 41341 0.970 1978 919314 50705 22156 0.640 1979 1219817 77061 60 0.001 1980 895139 126990 306 0.000 1981 1669378 134356 51420 0.355 1982 779065 112506 92360 0.662 1983 3054354 83804 63523 0.698 1984 1159832 124083 56012 0.502 1985 1216972 153601 39142 0.302 1986 904968 140132 70764 0.503 1987 2153505 131338 44360 0.323 1988 926242 156819 35591 0.270 1989 883476 174318 34026 0.237 1990 440702 165829 44693 0.333 1991 385237 134854 28529 0.245 1992 797238 111317 28985 0.268 1993 600226 105371 31778 0.237 1994 849893 96745 24430 0.223 1995 652959 76959 29575 0.258 1996 847295 123121 26105 0.168 1997 1512594 77857 35233 0.490 1998 485023 101025 33353 0.458 1999 301944 84392 29736 0.295 2000 1619398 72317 18322 0.215 2001 983427 115037 24556 0.247 2002 977738 131339 32914 0.265 2003 361862 124161 28081 0.247 2004 226438 107306 25021 0.215 2005 218745 85284 14129 0.133 2006 435783 76813 27346 0.275 2007 596324 68816 29616 0.395 2008 61717

Average 1611993 187120 61106 0.354


5.4.31 Norway pout in Division VIa (West of Scotland)

Single-stock exploitation boundaries The available information is inadequate to evaluate stock trends relative to risk, so the state of the stock is unknown. The only data available are official landings statistics which have been highly variable and do not provide an adequate basis for scientific advice. Source of information Report of the Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak, 7–13 May 2008. ICES CM 2008/ACOM:09.

05000

1000015000200002500030000350004000045000

year

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

Figure 5.4.31.1 Norway pout in Division VIa (West of Scotland) Total landings (tonnes).


Table 5.4.31.1 Norway pout in Division VIa (West of Scotland) Total landings (tonnes) by Subdivision and country.

Year Denmark Faroe

Islands Germany Netherlands UK –

Eng+Wales+N.Irl. UK –

Scotland Total 1987 37714 553 38267 1988 5849 376 517 6742 1989 28180 11 5 28196 1990 3316 0.5 3317 1991 4348 4348 1992 5147 10 1 5158 1993 7338 0.5 7339 1994 14147 1 0.5 14149 1995 24431 1 7 24439 1996 6175 7 140 6322 1997 9549 13 9562 1998 7186 7186 1999 4624 1 4625 2000 2005 2005 2001 3214 3214 2002 4815 4 4819 2003 6395 2 6397 2004 2281 4 2285 2005 0 0 2006 32 32 2007 0 0


5.4.32 Sandeel in Division VIa (West of Scotland)

Single-stock exploitation boundaries The available information is inadequate to evaluate stock trends relative to risk, so the state of the stock is unknown. The only recent data available are official landings statistics which have been highly variable and do not provide an adequate basis for scientific advice. The stock was last assessed in 1996. Source of information ICES. 2008. Report of the Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak, 7–13 May 2008 (ICES CM 2008/ACFM:09).

0

5000

10000

15000

20000

25000

Year

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

Figure 5.4.32.1 Sandeel in Division VIa, total landings (tonnes). Table 5.4.32.1 Sandeel in Division VIa, total landings (tonnes) by country.

Year Denmark Faroe Islands UK - Scotland Total 1987 - - 14479 14479 1988 - - 24465 24465 1989 - - 18785 18785 1990 - - 16515 16515 1991 - - 8532 8532 1992 - - 4985 4985 1993 80 - 6156 6236 1994 - - 10627 10627 1995 - - 7111 7111 1996 - - 13257 13257 1997 - - 12679 12679 1998 - - 5320 5320 1999 - - 2627 2627 2000 - . 5771 5771 2001 - - 295 295 2002 - - 706 706 2003 - - - 0 2004 - - 566 566 2005 - - - 0 2006 - - - 0 2007 . 57 . 57


5.4.33 Nephrops in Division VIa Nephrops are limited to a muddy habitat. This means that the distribution of suitable sediment defines the species distribution and the stocks are therefore assessed as three separate Functional Units (Figure 5.4.33.1). There are also some smaller catches from areas outside these Functional Units. There are three Functional Units in Division VIa: North Minch (FU 11), South Minch (FU 12), and Firth of Clyde (FU 13).

Section FU no. Name ICES Divisions Statistical rectangles

5.4.33.1 11 North Minch VIa 44–46 E3-E4 5.4.33.2 12 South Minch VIa 41–43 E2-E4 5.4.33.3 13 Clyde VIa 39–40 E4-E5

-10 -8 -6 -4 -2

5456

5860

Longitude

Latti

tude

VIa

VIIa

North Minch

South Minch

Cly de

IrishSeaEastIrish Sea West

Figure 5.4.33.1 Nephrops Functional Units in Division VIa.

State of the stocks Underwater TV surveys of the Nephrops stocks in the Functional Units of Division VIa indicate a decline in abundance in 2007 following increases up to 2006 when the highest population abundances in the time-series were observed. The most marked decline was in the South Minch, with a smaller decline in the North Minch and Clyde. Trends in landings of different Functional Units are shown in Figure 5.4.33.2. Length composition indicators have been stable over a long period of time. Overall the stocks are perceived to be stable. Management objectives No management objectives have been set for these stocks.


Reference points Precautionary reference points have not been determined for Nephrops. F0.1 estimates from a yield-per-recruit analysis based on a combined sex–length cohort analysis (LCA) could be used as an appropriate harvest ratio for Nephrops stocks. Single-stock exploitation boundaries Given the apparent stability of the stocks, current levels of exploitation and effort appear to be sustainable. ICES recommends not to increase effort and catches above the recent average values (2006–2007). An overview of advice for different Functional Units is presented in the table below. Management considerations Landings by some fleets prior to 2006 are thought to have been underreported. The implementation of the Buyers and Sellers legislation in the UK in 2006 and “sales notes” in Ireland in 2007, coupled with the increased TAC, is thought to have improved the reliability of reported landings data. Therefore the advice for this stock refers to average landings 2006-2007 only and does not use landings data prior to 2006. There have been important developments in the methodology to assess the status of Nephrops stocks. The use of Underwater TV surveys (UWTV) has enabled the development of fishery-independent indicators of abundance. STECF (2005) has suggested that a combination of an absolute abundance estimate from an UWTV survey, a harvest rate based on F0.1 from a combined sex–length cohort analysis (LCA), the mean weight, and selection pattern from the commercial fishery could be used to calculate appropriate landings. The approach has been further elaborated and tested in an ICES workshop in 2007 (ICES, 2007) and reviewed in 2008. The conclusion of the review was that the use of UWTV surveys for absolute abundance estimates could lead to an overestimation bias due to misidentification of burrows, habitat estimation, and occupancy rate. The amount of overestimation bias could not be specified. ICES has therefore not based the advice for 2009 on the approach indicated above, but has used the UWTV survey only as relative indicator of abundance. ICES will organize a follow-up workshop in 2008 or 2009 to further develop the approach to Nephrops advice. UWTV surveys do not take account of smaller areas containing Nephrops populations which are not well surveyed and do not have adequate sediment distribution to define abundance adequately. In particular landings are also made from the sea loch areas by creel fishers (average creel landings 2005–2007: 1737 tonnes). The creel components have been taken into account in the catch advice for the various Functional Units. There are also Nephrops catches in “other rectangles” in Division VIa, e.g. from offshore areas adjacent to Stanton Bank where Irish fishers frequently operate from the shelf edge. To provide some guidance on appropriate future landings for these areas, the use of average landings of 250 tonnes (2005–2007) could be considered. Management of Nephrops is at the Division VIa level (both in terms of TACs and effort) which does not provide adequate safeguards to ensure that TACs are commensurate with effort or that both these management control measures are applied at a scale appropriate to the resources in each Functional Unit. The current situation allows for catches to be taken anywhere in the ICES Division and this could imply inappropriate harvest rates from some parts. Vessels are free to move between grounds, allowing effort to develop on some grounds in a largely uncontrolled way. Management at the FU level would address this problem. Bycatches of cod are generally low in the Division VIa Nephrops fisheries (STECF, 2005). Nevertheless, inshore areas have been important for young cod in the past and have been observed in these areas more recently, albeit in low abundance – any emerging year classes should not be subject to mortality as bycatch in smaller-mesh fisheries. A continuing problem is the capture of juvenile haddock and whiting, which are discarded at a high rate and whose populations are presently much reduced. This problem can be addressed with the use of more selective gear. Efforts are being made in Scotland through the Conservation Credits scheme, requiring vessels targeting Nephrops to use gear with larger square-meshed panels (110 mm). Subject to evaluation of the effectiveness of these measures, further action may be required to reduce bycatch. There are no Functional Units in ICES Division VIb, but occasional small landings are made (Table 5.4.33.3). Impacts of fisheries on the ecosystem Trawling for Nephrops results in bycatch and discards of other species, including cod, haddock, and whiting.


Factors affecting the fisheries and the stock Regulations and their effects The introduction of the “buyers and sellers” regulations in 2006 considerably tightened up the levels of reporting for Nephrops, and the landings figures since then are considered to be more reliable. Recent increases in landings and lpue may result from the increase in reporting levels and do not necessarily reflect changes to the stock. Impacts of the environment on the fish stocks The similarity in patterns of change in abundance between the grounds which extend up the entire west coast of Scotland, may indicate a large-scale environmental influence affecting recruitment dynamics. Scientific basis Data and methods Assessments of the Nephrops Functional Units of Division VIa utilized a number of approaches including TV surveys, length composition information, and basic fishery data such as landings and effort. Owing to uncertainties in the accuracy of historic landings and to inaccurate effort figures in some fisheries, increasing attention is paid to survey information and size composition data as an indicator of stock stability. Uncertainties in assessment and forecast UWTV surveys are used to indicate abundance trends. Since they are based on a standardized fishery-independent survey method, they should give a more accurate indication of abundance trends than lpue data that are subject to uncertainties associated with changes in fishing practices. However, UWTV surveys cannot at this time be used for estimates of absolute abundance (i.e., the actual number or biomass of Nephrops in the population) because of uncertainty in the occupancy rate of burrows, misidentification of burrows, and other factors (ICES, 2007). It would be desirable in the future to have scientifically defensible estimates of absolute abundance based on UWTV surveys and/or other sources of information. ICES will conduct a rigorous evaluation of UWTV surveys with a view toward absolute abundance estimation, including identification of potential research needs, prior to giving advice on these stocks. Depending on the outcome of the evaluation, it may be appropriate to give advice next year rather than in 2010, as would normally be the case. The calculations of harvest ratio and F0.1 are all based on yield-per-recruit analyses and therefore apply to stocks in equilibrium. However, it is unlikely that the Nephrops stocks to which the approach has been applied are actually in equilibrium due to variable recruitment. F0.1 estimates may vary substantially in subsequent years. Commercial catch data may have been subject to misreporting. Simulation studies (Dobby et al., 2007) which derived yield-per-recruit curves that do not rely on commercial catch data could be used to provide a more robust method to derive F0.1. Comparison with previous assessment and advice The indicators used to assess the status of Nephrops stocks are largely the same as in 2006. The advice in 2006 was based on a 15% harvest ratio for several of the Nephrops stocks, based in turn on UWTV surveys interpreted as estimates of absolute abundance. This year, UWTV surveys are used as indicators of relative abundance because they are deemed inappropriate for absolute abundance estimation at this time (see discussion above). For stocks where UWTV surveys are not available, the advice is on the same basis as in 2006. Source of information ICES. 2008. Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 15–21 May 2008 (ICES

CM 2008/ACOM:08). ICES. 2007. Workshop on the Use of UWTV Surveys for Determining Abundance in Nephrops Stocks throughout

European Waters. 17–21 April 2007, Heraklion, Crete, Greece. ICES CM 2007/ACFM:14. 198 pp. Dobby, H., Bailey, N., and Campbell, N. 2007. The use of underwater TV surveys in the provision of advice for Nephrops

stocks around Scotland. ICES CM 2007/O:23. STECF. 2005. Commission Staff Working Paper. 21st Report of the Scientific, Technical and Economic Committee for

Fisheries (Second Plenary Meeting). Brussels, 7–11 November 2005.


Table 5.4.33.1 Nephrops in Division VIa. Single stock exploitation boundaries (advice), management and landings. by Functional Unit plus Other rectangles.

Year North Minch (FU11)

South Minch (FU12)

Firth of Clyde (FU13)

Other rectangles

Total advice Agreed TAC 1)

ICES landings

1992 ~11.4 12.0 10.8 1993 ~11.3 12.0 11.3 1994 11.3 12.6 11.1 1995 11.3 12.6 12.8 1996 11.3 12.6 11.2 1997 11.3 12.6 11.2 1998 11.3 12.6 11.2 1999 11.3 12.6 11.5 2000 11.3 12.6 11.0 2001 11.3 11.34 10.9 2002 11.3 11.34 10.5 2003 11.3 11.34 10.8 2004 11.3 11.3 10.4 2005 11.3 12.7 10.5 2006 - 17.7 13.7 2007 3.2 7.2 3.765 0.8 15.0 19.9 16.3 2008 3.2 7.2 3.765 0.8 15.0 19.9 2009 < 4.1 < 5.0 < 5.7 < 0.3 < 15.1

Weights in ‘000 t. 1) Subarea VI and EC waters of Division Vb.


Landings by Functional Units ( thousands tonnes)

0

2

4

6

8

10

12

14

16

1819

81

1983

1985

1987

1989

1991

1993

1995

1997

1999

2001

2003

2005

2007

OthersFU13FU11FU12

Figure 5.4.33.2 Nephrops in Division VIa. Landing (thousands tonnes) by FU and Other rectangles.

Table 5.4.33.2 Nephrops in Division VIa. Landings (tonnes) by Functional Unit plus Other rectangles, 1981–

2007. Creel landings are included.

Year FU 11 FU 12 FU 13 Other Total1981 2861 3651 2968 39 95191982 2799 3552 2623 27 90011983 3196 3412 4077 34 107191984 4144 4300 3310 36 117901985 4061 4008 4285 104 124581986 3382 3484 4341 89 112961987 4083 3891 3007 257 112381988 4035 4473 3665 529 127021989 3205 4745 2812 212 109741990 2544 4430 2912 182 100681991 2792 4442 3038 255 105271992 3560 4237 2805 248 108491993 3192 4455 3342 344 113321994 3616 4415 2629 441 111011995 3656 4680 3989 460 127851996 2871 3995 4060 239 111651997 3046 4345 3618 243 112521998 2441 3730 4843 157 111711999 3257 4051 3752 438 114982000 3246 3952 3419 421 110382001 3259 3992 3182 420 108532002 3440 3305 3383 397 105252003 3268 3879 3171 433 107512004 3135 3868 3025 403 104312005 2984 3843 3423 254 105042006 4160 4554 4778 241 137332007* 3968 5451 6656 258 16333

*provisional


Table 5.4.33.3 Nephrops in Divisions VIb. Nominal catch (tonnes) as officially reported to ICES. Creel landings are included. There are no Functional Units in ICES Division VIb, but occasional small landings are made.

ICES

Division VIb France Germany Ireland Spain UK-Eng+ Wales+N.Irl.

UK - Scotland Total

1986 0 0 0 8 0 0 8 1987 0 0 0 18 11 0 29 1988 0 0 0 27 4 0 31 1989 0 0 0 14 0 0 14 1990 0 0 0 10 1 0 11 1991 0 0 0 30 0 0 30 1992 0 0 0 2 4 1 7 1993 0 0 0 2 6 9 17 1994 0 0 0 5 16 5 26 1995 1 0 0 2 26 1 30 1996 0 6 0 5 65 5 81 1997 0 0 1 3 88 23 115 1998 0 0 1 6 46 7 60 1999 0 0 0 5 2 5 12 2000 2 0 8 3 4 4 21 2001 1 0 1 14 2 7 25 2002 1 0 0 7 3 7 18 2003 0 0 1 5 6 18 30 2004 0 0 0 2 20 22 2005 3 na 1 1 12 17 2006 0 0 0 0 4 4 2007 0 0 0 na 2.5 2.5


5.4.33.1 Nephrops in North Minch (FU 11) State of the stock The UWTV survey indicates that the population had been increasing until 2006 and then decreased in 2007. The index in 2007 is at a similar level as the period 2002–2005. Overall the stock is perceived to be stable. Single-stock exploitation boundaries Exploitation boundaries in relation to precautionary considerations The current fishery appears sustainable. Therefore, ICES recommends that Nephrops fisheries should not be allowed to increase relative to the past two years (2006–2007). This corresponds to landings of no more than 4100 tonnes for the North Minch stock. Management considerations Landings by some fleets prior to 2006 are thought to have been underreported. The implementation of the Buyers and Sellers legislation in the UK in 2006 and “sales notes” in Ireland in 2007, coupled with the increased TAC, is thought to have improved the reliability of reported landings data. Therefore the advice for this stock refers to average landings 2006-2007 only and does not use landings data prior to 2006. The decline in abundance in 2007 reduced the stock from the highest estimate in the series in 2006 to a level comparable with the period 2002 to 2005. Creel fishing takes place mainly in the sea-loch areas. Overall effort in creel numbers is not known and measures to regulate the fishery are not in place. There is a need to ensure that the combined effort from all forms of fishing is taken into account when managing this stock. Impacts of fisheries on the ecosystems There is a bycatch of other species in Nephrops fisheries in the North Minch. Estimates of discards of whiting and haddock are high in Division VIa. Bycatches of cod are generally low in Division VIa in the Nephrops fisheries, and a scheme involving square-meshed panels and real-time closures has been introduced to reduce them further. Factors affecting the fisheries and the stock The effects of regulations The minimum landing size for Nephrops is 20 mm carapace length (CL), and less than 0.5% of the animals are landed under size. Discarding rates of Nephrops in the North Minch in 2007 were 25% by number. The introduction of the “buyers and sellers” regulations in 2006 in the UK is considered to have improved the accuracy in the levels of reporting for Nephrops, and the landings figures since then are considered to be more reliable. Changes in fishing technology and fishing patterns Due to reduced availability of Nephrops in the summers of 2006 and 2007, and poor weather over the summer of 2007, some local boats left the North Minch after July to fish in the seasonal Moray Firth squid fishery. Scientific basis Data and methods UWTV survey estimates are available for this stock in 1994 and 1996 and for a continuous period from 1998 onwards. Uncertainties in assessment and forecast UWTV surveys are used to indicate abundance trends. Since they are based on a standardized fishery-independent survey method, they should give a more accurate indication of abundance trends than lpue data that are subject to uncertainties associated with changes in fishing practices. However, UWTV surveys cannot at this time be used for estimates of absolute abundance (i.e., the actual number or biomass of Nephrops in the population) because of uncertainty in the occupancy rate of burrows, misidentification of burrows, and other factors (ICES, 2007).


It would be desirable in the future to have scientifically defensible estimates of absolute abundance based on UWTV surveys and/or other sources of information. ICES will conduct a rigorous evaluation of UWTV surveys with a view toward absolute abundance estimation, including identification of potential research needs, prior to giving advice on these stocks. Depending on the outcome of the evaluation, it may be appropriate to give advice next year rather than in 2010, as would normally be the case. Comparison with previous assessment and advice The indicators used to assess the status of Nephrops stocks are largely the same as in 2006. The advice in 2006 was based on a 15% harvest ratio for several of the Nephrops stocks, based in turn on UWTV surveys interpreted as estimates of absolute abundance. This year, UWTV surveys are used as indicators of relative abundance because they are deemed inappropriate for absolute abundance estimation at this time (see discussion above). Nephrops in North Minch (FU 11). Single stock exploitation boundaries (advice), management and landings.

Year ICES advice Advice for North Minch

(FU11)

Recommended landings for VIa

Agreed TAC1)

ICES Landings (FU11)

1989 3.2 1990 2.5 1991 2.8 1992 maintain current effort ~11.4 12.0 3.6 1993 maintain current effort ~11.3 12.0 3.2 1994 maintain current effort 11.3 12.6 3.6 1995 maintain current effort 11.3 12.6 3.7 1996 maintain current effort 11.3 12.6 2.9 1997 as for 1996 11.3 12.6 3.0 1998 maintain current effort 11.3 12.6 2.4 1999 as for 1998 11.3 12.6 3.3 2000 maintain current effort 11.3 12.6 3.2 2001 as for 2000 11.3 11.34 3.3 2002 maintain current effort 11.3 11.34 3.4 2003 as for 2002 11.3 11.34 3.3 2004 maintain current effort 11.3 11.3 3.1 2005 as for 2004 11.3 12.7 3.0 2006 No increase in effort - 17.7 4.2 2007 No increase effort and harvest rate of 15% 3.2 15.0 19.9 4.0 2008 As for 2007 3.2 15.0 19.9 2009 No increase effort and recent average

catch < 4.1 15.1



Landings - International

0

1000

2000

3000

4000

5000

1960 1965 1970 1975 1980 1985 1990 1995 2000 2005

Land

ings

(ton

nes)

UK Scotland - All gearsUK Scotland - Nephrops traw lersInternationalUK Scotland - Creel

Figure 5.4.33.1.1 Nephrops, North Minch (FU11). Long-term landings.

North Minch TV Survey

0

200

400

600

800

1000

1200

1400

1600

1800

1992 1994 1996 1998 2000 2002 2004 2006 2008

Nep

hrop

s ab

unda

nce

(mill

ions

)

Figure 5.4.33.1.2 Nephrops, North Minch (FU 11). Time-series of TV survey abundance estimates, with 95%

confidence intervals, 1994–2007 (no survey 1995 and 1997). Abundance is expressed as the number of individuals, but for the purpose of this advice, the figure is interpreted as relative abundance.


Table 5.4.33.1.1 Nephrops in North Minch (FU 11). Official landings (tonnes).

2320 170 371 28612323 105 371 27992784 95 317 31963449 161 534 41443236 117 708 40612642 203 537 33823458 143 482 40833449 149 437 40352603 112 490 32051941 134 469 25442228 125 439 27922978 150 432 35602699 85 408 31922916 246 454 36162940 184 532 36562355 147 369 28712553 102 391 30462023 67 351 24412791 56 410 32572695 28 523 32462651 41 567 32592775 79 586 34402607 44 617 32682400 25 710 31352267 18 699 29843446 17 697 41603362 16 590 3968

* provisional na = not available** There are no landings by other countries from this FU

2005

1998199920002001

20062007

1984

YearUK Scotland

Nephrops trawl

Other trawl

20042003

Creel

19951996

1989

198119821983

1994

1997

Total

2002

19851986

1990199119921993

19871988


5.4.33.2 Nephrops in the South Minch (FU 12) State of the stock The UWTV survey indicates that the population has fluctuated without trend at a higher level between 2001 and 2006. A decrease occurred in 2007 to an abundance below the long-term average for the stock. Overall the stock is perceived to be stable. Single-stock exploitation boundaries Exploitation boundaries in relation to precautionary considerations The current fishery appears sustainable. Therefore, ICES recommends that Nephrops fisheries should not be allowed to increase relative to the past two years (2006–2007). This corresponds to landings of no more than 5000 tonnes for the South Minch stock. Management considerations Landings by some fleets prior to 2006 are thought to have been underreported. The implementation of the Buyers and Sellers legislation in the UK in 2006 and “sales notes” in Ireland in 2007, coupled with the increased TAC, is thought to have improved the reliability of reported landings data. Therefore the advice for this stock refers to average landings 2006-2007 only and does not use landings data prior to 2006. Creel fishing takes place mainly in the sea-loch areas. Overall effort in creel numbers is not known and measures to regulate the fishery are not in place. There is a need to ensure that the combined effort from all forms of fishing is taken into account when managing this stock. Impacts of fisheries on the ecosystems There is a bycatch of other species in the Nephrops fisheries in the area of the South Minch. Estimates of discards of whiting and haddock are high in Division VIa. Bycatches of cod are generally low in Division VIa in the Nephrops fisheries, and a scheme involving square-meshed panels and real-time closures has been introduced to reduce them further. Factors affecting the fisheries and the stock The effects of regulations The minimum landing size for Nephrops is 20 mm carapace length (CL), and less than 0.5% of the animals are landed under size. Discarding rates of Nephrops in the South Minch in 2007 were 21% by number. The introduction of the “buyers and sellers” regulations in 2006 in the UK considerably tightened up the levels of reporting for Nephrops, and the landings figures since then are considered to be more reliable. Changes in fishing technology and fishing patterns Between July and November local inshore boats moved round to the Moray Firth for the seasonal squid fishery – this was smaller in 2006 compared to previous years but increased again in 2007. During the winter months fishing activity is severely reduced in the South Minch due to the weather and small boats are often restricted to fishing in the sheltered sea-lochs. Scientific basis Data and methods UWTV survey estimates are available for this stock for a continuous period from 1995 onwards. Information from the fishing industry The industry in this area reported lower catch rates in 2007.


Uncertainties in the assessment and forecast UWTV surveys are used to indicate abundance trends. Since they are based on a standardized fishery-independent survey method, they should give a more accurate indication of abundance trends than lpue data that are subject to uncertainties associated with changes in fishing practices. However, UWTV surveys cannot at this time be used for estimates of absolute abundance (i.e., the actual number or biomass of Nephrops in the population) because of uncertainty in the occupancy rate of burrows, misidentification of burrows, and other factors (ICES, 2007). It would be desirable in the future to have scientifically defensible estimates of absolute abundance based on UWTV surveys and/or other sources of information. ICES will conduct a rigorous evaluation of UWTV surveys with a view toward absolute abundance estimation, including identification of potential research needs, prior to giving advice on these stocks. Depending on the outcome of the evaluation, it may be appropriate to give advice next year rather than in 2010, as would normally be the case. Comparison with previous assessment and advice The indicators used to assess the status of Nephrops stocks are largely the same as in 2006. The advice in 2006 was based on a 15% harvest ratio for several of the Nephrops stocks, based in turn on UWTV surveys interpreted as estimates of absolute abundance. This year, UWTV surveys are used as indicators of relative abundance because they are deemed inappropriate for absolute abundance estimation at this time (see discussion above). Nephrops in the South Minch (FU 12). Single stock exploitation boundaries (advice), management and landings.

Year ICES advice ICES Advice for South Minch

(FU12)

Recommended landings for VIa

Agreed TAC 1)

ICES landings (FU12)

1989 4.7 1990 4.4 1991 4.4 1992 maintain current effort ~11.4 12.0 4.2 1993 maintain current effort ~11.3 12.0 4.5 1994 maintain current effort 11.3 12.6 4.4 1995 maintain current effort 11.3 12.6 4.7 1996 maintain current effort 11.3 12.6 4.0 1997 as for 1996 11.3 12.6 4.3 1998 maintain current effort 11.3 12.6 3.7 1999 as for 1998 11.3 12.6 4.1 2000 maintain current effort 11.3 12.6 4.0 2001 as for 2000 11.3 11.34 4.0 2002 maintain current effort 11.3 11.34 3.3 2003 as for 2002 11.3 11.34 3.9 2004 maintain current effort 11.3 11.3 3.9 2005 as for 2004 11.3 12.7 3.8 2006 No increase in effort - 17.7 4.6 2007 No increase in effort and harvest rate of

15% 7.2 15.0 19.9 5.5

2008 as for 2007 7.2 15.0 19.9 2009 No increase effort and recent average catch < 5.0 15.1




0

1000

2000

3000

4000

5000

6000

1960 1965 1970 1975 1980 1985 1990 1995 2000 2005

Land

ings

(ton

nes)


Figure 5.4.33.2.1 Nephrops, South Minch (FU 12). Long-term landings.

0

500

1000

1500

2000

2500

3000

3500

1994 1996 1998 2000 2002 2004 2006 2008

Nep

hrop

s ab

unda

nce

(mill

ions

)

0

500

1000

1500

2000

2500

3000

3500

1994 1996 1998 2000 2002 2004 2006 2008

Nep

hrop

s ab

unda

nce

(mill

ions

)

Figure 5.4.33.2.2 Nephrops, South Minch (FU 12). Time-series of TV survey abundance estimates, with 95% confidence intervals, 1995–2007. Abundance is expressed as the number of individuals, but for the purpose of this advice, the figure is interpreted as relative abundance.


Table 5.4.33.2.1 Nephrops, South Minch (FU 12). Nominal landings of Nephrops, 1981–2007, as reported officially to ICES.

2965 254 432 3651 0 0 36512925 207 420 3552 0 0 35522595 361 456 3412 0 0 34123228 478 594 4300 0 0 43003096 424 488 4008 0 0 40082694 288 502 3484 0 0 34842927 418 546 3891 0 0 38913544 364 555 4463 10 0 44733846 338 561 4745 0 0 47453732 262 436 4430 0 0 44303597 341 503 4441 1 0 44423479 208 549 4236 1 0 42373608 193 649 4450 5 0 44553743 265 404 4412 3 0 44153442 716 508 4666 14 0 46803107 419 468 3994 1 0 39953519 331 492 4342 3 1 43452851 340 538 3729 0 0 37303165 359 513 4037 0 14 40512939 312 699 3950 0 2 39522823 393 767 3983 0 9 39922234 315 742 3291 0 14 33052812 203 858 3873 0 6 38792865 104 880 3849 0 19 38682810 46 953 3809 1 31 38413569 19 922 4510 9 35 45544436 8 958 5402 19 30 5451

* provisional na = not available

20062007

Nephrops trawl

Other trawl Creel

2003

2005

Total

2004

19811982198319841985

Other UK IrelandYearUK Scotland

Sub-total

1999200020012002

1995199619971998

198619871988198919901991199219931994


5.4.33.3 Nephrops in the Firth of Clyde (FU 13) State of the stock The UWTV survey indicates that the population increased steadily between 1999 and 2006, but declined in the most recent year (2007) to a level more typical of the period 1996 to 2002. Overall the stock is perceived to be stable. Single-stock exploitation boundaries Exploitation boundaries in relation to precautionary considerations The current fishery appears sustainable. Therefore, ICES recommends that the Nephrops fisheries should not be allowed to increase relative to the past two years (2006–2007). This corresponds to landings of no more than 5700 tonnes for the Firth of Forth stock. Management considerations Landings by some fleets prior to 2006 are thought to have been underreported. The implementation of the Buyers and Sellers legislation in the UK in 2006 and “sales notes” in Ireland in 2007, coupled with the increased TAC, is thought to have improved the reliability of reported landings data. Therefore the advice for this stock refers to average landings 2006-2007 only and does not use landings data prior to 2006. Creel fishing takes place mainly in the sea-loch areas. Overall effort in terms of creel numbers is not known and measures to control numbers are not in place. There is a need to ensure that the combined effort from all forms of fishing is taken into account when managing this stock. Impacts of fisheries on the ecosystems There is a bycatch of other species in Nephrops fisheries in the Firth of Clyde. Estimates of discards of whiting and haddock are high in Division VIa. Bycatches of cod are generally low in Division VIa in the Nephrops fisheries and a scheme involving square-meshed panels and real-time closures has been introduced to reduce them further. A seasonal closure (early spring) in the southwestern part of the Firth of Clyde is in place to protect spawning cod although Nephrops vessels are derogated to fish in those parts where mud sediments are distributed. Factors affecting the fisheries and the stock The effects of regulations The minimum landing size for Nephrops is 20 mm carapace length (CL), and less than 0.5% of the animals are landed under size. Discarding rates of Nephrops for the Firth of Clyde in 2007 were 23% by number. Mobile gear is banned in the inshore Clyde from Friday night to Sunday night, as are vessels greater than 21m in length. However, creel fishing is not affected by this legislation. The introduction of the “buyers and sellers” regulations in 2006 in the UK considerably tightened up the levels of reporting for Nephrops, and the landings figures since then are considered to be more reliable. Changes in fishing technology and fishing patterns An increasing number of creel boats operate in the Clyde. Creeling activity often takes place during the weekend when the trawlers cannot fish due to the ban. One third of the creelers operate throughout the year, the rest prosecute a summer fishery. Scientific basis Data and methods UWTV survey estimates are available for this stock for a continuous period from 1995 onwards.


Information from the fishing industry The industry reported that catch rates had been increasing over the past three years but size had declined a little, particularly in the North of the Clyde. Uncertainties in assessment and forecast UWTV surveys are used to indicate abundance trends. Since they are based on a standardized fishery-independent survey method, they should give a more accurate indication of abundance trends than lpue data that are subject to uncertainties associated with changes in fishing practices. However, UWTV surveys cannot at this time be used for estimates of absolute abundance (i.e., the actual number or biomass of Nephrops in the population) because of uncertainty in the occupancy rate of burrows, misidentification of burrows, and other factors (ICES, 2007). It would be desirable in the future to have scientifically defensible estimates of absolute abundance based on UWTV surveys and/or other sources of information. ICES will conduct a rigorous evaluation of UWTV surveys with a view toward absolute abundance estimation, including identification of potential research needs, prior to giving advice on these stocks. Depending on the outcome of the evaluation, it may be appropriate to give advice next year rather than in 2010, as would normally be the case. Comparison with previous assessment and advice The indicators used to assess the status of Nephrops stocks are largely the same as in 2006. The advice in 2006 was based on a 15% harvest ratio for several of the Nephrops stocks, based in turn on UWTV surveys interpreted as estimates of absolute abundance. This year, UWTV surveys are used as indicators of relative abundance because they are deemed inappropriate for absolute abundance estimation at this time (see discussion above). Nephrops in the Firth of Clyde (FU 13). Single stock exploitation boundaries (advice), management and landings.

Year ICES advice ICES Advice for Firth of Clyde

(FU13)

Recommended landings in VIa

Agreed TAC1)

ICES landings (FU13)

1989 2.8 1990 2.9 1991 3.0 1992 maintain current effort ~11.4 12.0 2.8 1993 maintain current effort ~11.3 12.0 3.3 1994 maintain current effort 11.3 12.6 2.6 1995 maintain current effort 11.3 12.6 4.0 1996 maintain current effort 11.3 12.6 4.0 1997 as for 1996 11.3 12.6 3.6 1998 maintain current effort 11.3 12.6 4.8 1999 as for 1998 11.3 12.6 3.8 2000 maintain current effort 11.3 12.6 3.4 2001 as for 2000 11.3 11.34 3.2 2002 maintain current effort 11.3 11.34 3.4 2003 as for 2002 11.3 11.34 3.2 2004 maintain current effort 11.3 11.3 3.0 2005 as for 2004 11.3 12.7 3.4 2006 No increase in effort - 17.7 4.8 2007 No increase in effort and harvest rate no

more than 15% 3.765 15.0 19.9 6.7

2008 as for 2007(no new advice) 3.765 15.0 19.9 2009 No increase effort and recent average

catch < 5.7 15.1




0

1000

2000

3000

4000

5000

6000

7000

1960 1965 1970 1975 1980 1985 1990 1995 2000 2005

Land

ings

(ton

nes)


Figure 5.4.33.3.1 Nephrops, Firth of Clyde (FU 13). Long-term landings.

0

400

800

1200

1600

2000

2400

1994 1996 1998 2000 2002 2004 2006 2008

Nep

hrop

s ab

unda

nce

(mill

ions

)

Figure 5.4.33.3.2 Nephrops, Firth of Clyde (FU 13). Time-series of TV survey abundance estimates, with 95%

confidence intervals, 1995–2007. Abundance is expressed as the number of individuals, but for the purpose of this advice, the figure is interpreted as relative abundance.


Table 5.4.33.3.1 Nephrops, Firth of Clyde (FU 13). Nominal landings of Nephrops, 1981–2007, as reported officially to ICES.

2498 404 66 2968 0 29682373 171 79 2623 0 26233890 120 53 4063 14 40773069 154 77 3300 10 33103921 293 64 4278 7 42854074 175 79 4328 13 43412859 80 65 3004 3 30073507 108 43 3658 7 36652577 184 35 2796 16 28122732 122 24 2878 34 29122845 145 25 3015 23 30382532 246 10 2788 17 28053199 110 5 3314 28 33422503 49 28 2580 49 26293767 132 26 3925 64 39893880 111 27 4018 42 40603486 44 25 3555 63 36184539 81 40 4660 183 48433475 29 38 3542 210 37523143 63 76 3282 137 34192889 67 94 3050 132 31823074 53 105 3232 151 33832954 20 117 3091 80 31712659 18 90 2767 258 30253166 14 95 3275 148 34234356 0 178 4534 244 47786069 0 221 6290 366 6656

* provisional ** Total also includes Rep. of Ireland 2007

Other trawl

2003

20052004

YearUK Scotland

Sub-totalTotal **Other UKNephrops

trawl Creel

19871988198919901991199219931994

1981198219831984

200020012002

2006

19851986

19961995

199719981999


5.4.34 Nephrops in Subarea VII Nephrops are limited to a muddy habitat. This means that the distribution of suitable sediment defines the species distribution and the stocks are therefore assessed as six separate Functional Units (Figure 5.4.34.1). There are also some smaller catches from areas outside these Functional Units.

Section FU no. Name ICES Divisions Statistical rectangles

5.4.34.1 14 Irish Sea East VIIa 35–38E6; 38E5 5.4.34.2 15 Irish Sea West VIIa 36E3; 35–37 E4–E5; 38E4 5.4.34.3 16 Porcupine Bank VIIb,c,j,k 31–36 D5–D6; 32–35 D7–D8 5.4.34.4 17 Aran Grounds VIIb 34–35 D9–E0 5.4.34.5 19 Ireland SW and SE coast VIIa,g,j 31–33 D9–E0; 31E1; 32E1–E2; 33E2–E3 5.4.34.6 20–22 Celtic Sea VIIg,h 28–30 E1; 28–31 E2; 30–32 E3; 31 E4

Figure 5.4.34.1 Nephrops Functional Units in Subarea VII (around Ireland).

State of the stocks Most stocks in this area appear to be stable in terms of abundance and size composition. The notable exception is the Porcupine Bank (FU 16) where effort in the fishery and mean size in the catches has increased in the past four years and where the lpues have declined in the in the past two years. Management objectives No management objectives have been set for these stocks. Reference points Precautionary reference points have not been determined for Nephrops. F0.1 estimates from a yield-per-recruit analysis based on a combined sex–length cohort analysis (LCA) could be used as an appropriate harvest ratio for Nephrops stocks.

13

15 14

20-2219

17

18

16

J


Single-stock exploitation boundaries Given the apparent stability of the stocks, current levels of exploitation and effort appear to be sustainable. ICES generally recommends not to increase effort and catches above the recent average values (2006–2007). The notable exception is the Porcupine Bank (FU 16) where ICES recommends a reduction in effort and catches. An overview of advice for the various Functional Units is presented in the table below. Management considerations There have been important developments in the methodology to assess the status of Nephrops stocks. The use of Underwater TV surveys (UWTV) has enabled the development of fishery-independent indicators of abundance. UWTV survey data are available for two of the Functional Units in this area. STECF (2005) has suggested that an absolute abundance estimate from an UWTV survey, in combination with a harvest rate based on F0.1 from a combined sex–length cohort analysis (LCA) and the mean weight and selection pattern from the commercial fishery could be used to calculate appropriate landings. The approach has been further elaborated and tested in an ICES workshop in 2007 (ICES, 2007) and reviewed in 2008. The conclusion of the review was that the use of UWTV surveys for absolute abundance estimates could lead to an overestimation bias due to misidentification of burrows, habitat estimation, and occupancy rate. The amount of overestimation bias could not be specified. ICES has therefore not based the advice for 2009 on the approach indicated above but has used the UWTV survey only as relative indicator of abundance. ICES will organize a follow-up workshop in 2008 or 2009 to further develop the approach to Nephrops advice. Current management of Nephrops in Subarea VII (both in terms of TACs and effort) does not provide adequate safeguards to ensure that local effort is sufficiently limited to avoid depletion of resources in separate Functional Units. The current situation allows for catches to be taken anywhere in the ICES Division and this could imply inappropriate harvest rates from some parts. More importantly, vessels are free to move between grounds, allowing effort to develop on some grounds in a largely uncontrolled way. This appears to have been a particular problem in the Porcupine Bank where a large increase in effort has occurred over the past four years. An overriding management consideration for these stocks is that management should be at a Functional Unit rather than the ICES Subarea level. Management at the Functional Unit level could provide the controls to ensure that catch opportunities and effort are compatible and in line with the scale of the resources in each of the stocks defined by the Functional Units. ICES has previously presented the advice for Nephrops organized by Management Areas, which were a combination of a few Functional Units. However, because the Management Areas where not areas used by managers, ICES now presents the advice by Functional Unit within the true management area: Subarea VII. Landings by some fleets prior to 2007 are thought to have been underreported. The implementation of the Buyers and Sellers legislation in the UK in 2006 and “sales notes” in Ireland in 2007, coupled with the increased TAC in 2007, is thought to have improved the reliability of reported landings data. The transition has been accompanied by a large change in reported landings and a significant recent increase in lpue for some countries that cannot completely be attributed to changes in the stock. Landings from the northwest coast of Ireland NW (FU 18) have previously been treated as a separate Functional Unit although landings have been negligible in recent years and there is no major Nephrops fishery in that area. ICES only reports landings statistics for that area. There are also Nephrops catches in “other rectangles” in Subarea VII. Landings from these “other rectangles” have been up to 800 t in the past, but since 2003 landings have been around 200 t. To provide some guidance on appropriate future landings for these areas, the use of landings of 200 tonnes could be considered." Scientific basis Data and methods Assessments of the Nephrops stocks around Ireland utilized a number of approaches. The fishery-independent data includes Underwater TV surveys (Western Irish Sea and Aran Ground) and trawl surveys (Western Irish Sea, Porcupine Bank, and Celtic Sea). There is some information on the length structure and sex ratio of either landings or catches in most areas. There are also landings and effort data from Nephrops-directed fleets. These are mainly not corrected for changes in fishing power or efficiency. Owing to uncertainties in the accuracy of historic landings in some fisheries, increasing attention is paid to survey information and size composition in the catch data as an indicator of stock stability.


Uncertainties in assessment and forecast In two stocks, UWTV surveys are used to indicate abundance trends. Since they are based on a standardized fishery-independent survey method, they should give a more accurate indication of abundance trends than lpue data that are subject to uncertainties associated with changes in fishing practices. However, UWTV surveys cannot at this time be used for estimates of absolute abundance (i.e., the actual number or biomass of Nephrops in the population) because of uncertainty in the occupancy rate of burrows, misidentification of burrows, and other factors (ICES, 2007). It would be desirable in the future to have scientifically defensible estimates of absolute abundance based on UWTV surveys and/or other sources of information. ICES will conduct a rigorous evaluation of UWTV surveys with a view toward absolute abundance estimation, including identification of potential research needs, prior to giving advice on these stocks. Depending on the outcome of the evaluation, it may be appropriate to give advice next year rather than in 2010, as would normally be the case. The calculations of harvest ratio and F0.1 are all based on yield-per-recruit analyses and therefore apply to stocks in equilibrium. However, it is unlikely that the Nephrops stocks to which the approach has been applied are actually in equilibrium due to variable recruitment. F0.1 estimates may vary substantially in subsequent years. Commercial catch data may have been subject to misreporting. Simulation studies (Dobby et al., 2007) which derived yield-per-recruit curves that do not rely on commercial catch data could be used to provide a more robust method to derive F0.1. Comparison with previous assessment and advice The indicators used to assess the status of Nephrops stocks are largely the same as in 2006 and the advice is also provided on the same basis. In two stocks, UWTV surveys are used to indicate abundance trends. Sources of information Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 15–21 May 2008 (ICES CM 2008/ACOM:08). Report of the Working Group on the Assessment of Southern Shelf Demersal Stocks, 30 April–6 May 2008 (ICES CM 2008/ACOM:12). Report of the Working Group on the Assessment of Southern Shelf Stocks of Hake, Monk, and Megrim, 30 April–7 May 2008 (ICES CM 2008/ACOM:07). Dobby, H., Bailey, N., and Campbell, N. 2007. The use of underwater TV surveys in the provision of advice for Nephrops stocks around Scotland. ICES CM 2007/O:23. ICES. 2007. Workshop on the Use of UWTV Surveys for Determining Abundance in Nephrops Stocks throughout European Waters. 17–21 April 2007, Heraklion, Crete, Greece. ICES CM 2007/ACFM:14. 198 pp. STECF. 2005. Commission Staff Working Paper. 21st Report of the Scientific, Technical and Economic Committee for Fisheries (Second Plenary Meeting). Brussels, 7–11 November 2005.


Nephrops in Subarea VII. Single stock exploitation boundaries (advice), management and landings. by Functional Unit plus Other rectangles.

Year Irish Sea East

(FU14)

Irish Sea

West (FU15)

Porcupine Bank (FU16)

Aran Grounds (FU17)

Ireland SW

and SE Coast

(FU19)

Celtic Sea

(FU20-22)

Other rec-

tangles 1)

Total advice

Agreed TAC

ICES landings

Manag. Area

MA J MA L MA M

Division VIIa VIIbcjk VIIfgh VII VII VII 1992 8.9 3.8 20.0 16.0 1993 9.4 ~4.0 20.0 16.9 1994 9.4 ~4.0 20.0 17.6 1995 9.4 ~4.0 20.0 18.9 1996 9.4 4.0 23.0 16.9 1997 9.4 4.0 23.0 19.3 1998 9.4 4.0 23.0 18.5 1999 9.4 4.0 23.0 19.3 2000 9.4 4.0 21.0 16.3 2001 9.4 4.0 18.9 15.9 2002 9.55 4.44 17.79 16.2 2003 9.55 4.44 17.79 15.6 2004 9.55 3.3 17.45 15.3 2005 9.55 3.3 19.544 15.8 2006 9.55 3.3 21.498 15.9 2007 - -- -- -- 25.153 18.5 2008 - -- -- -- -- 25.153 2009 <1.0 < 8.5 < 1.0 <0.9 <0.8 <5.3 < 0.2 < 18.7

Weights in ‘000 t.

1) Prior to advice for 2009, landings for other rectangles were included in ‘Management Areas (MA)’.


0

5000

10000

15000

20000

25000

1978

1980

1982

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

Other rectangles

Celtic Sea FU 20-22

Ireland SW& SEast coastFU19Aran Grounds FU17

Porcupine bank FU 16

Irish Sea East FU15

Irish Sea East FU14

0%

20%

40%

60%

80%

100%

1978

1980

1982

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

Figure 5.4.34.1 Nephrops in Subarea VII. Total landings and percentage of the total landings from Subarea VII by Functional Unit (FU) and from rectangle outside FUs.


Table 5.4.34.1 Nephrops in Subarea VII. Officially reported landings from all individual Functional Units within TAC Area VII.

Year Irish Sea

East FU14

Irish Sea East FU15

Porcupine bank FU 16

Aran GroundsFU17

Ireland SW& SE coast FU19

Celtic SeaFU 20–22

Other rectangles

Total Landings Subarea VII

1978 1039 4867 1744 272 0 4056 249 12227 1979 1010 5944 2269 481 0 4542 237 14483 1980 799 3022 2925 452 0 3535 205 10938 1981 873 4301 3381 442 0 3680 382 13059 1982 897 5004 4289 414 2 3316 239 14161 1983 765 5152 3426 210 0 3732 182 13467 1984 619 4500 3686 131 2 3691 190 12819 1985 520 4522 3967 324 1 3602 194 13130 1986 693 5393 2591 208 0 2638 117 11640 1987 475 5169 2499 147 2 2842 348 11482 1988 497 5447 2375 62 2 2769 300 11452 1989 438 8147 2115 831 899 3801 373 16604 1990 644 8308 1895 344 754 4050 367 16362 1991 859 9568 1640 519 1077 3132 350 17145 1992 495 7548 2015 412 888 4018 647 16023 1993 582 8112 1857 372 905 4374 745 16947 1994 513 7618 2512 729 390 4869 985 17616 1995 637 7799 2936 866 695 5223 753 18909 1996 511 7257 2230 525 888 4611 927 16949 1997 597 9979 2409 841 756 4027 652 19261 1998 389 9145 2155 1410 827 3835 741 18502 1999 625 10786 2132 1140 572 3532 487 19274 2000 567 8370 872 880 686 4579 308 16262 2001 532 7378 1163 913 809 4644 411 15850 2002 577 6914 1282 1154 1292 4603 403 16225 2003 377 7052 867 933 1226 4915 204 15574 2004 472 7398 1441 525 1066 4173 186 15261 2005 570 6529 2128 772 644 4932 230 15805 2006 628 7551 1941 631 658 4307 193 15909 2007 959 8461 1985 931 784 5261 142 18523

Average 639 6908 2291 596 528 4043 392 15395


5.4.34.1 Nephrops in Irish Sea East (FU14) State of the stock Mean size and sex ratios in the catches are stable. Landing per unit effort (lpue) indicators do not show signs of decrease in recent years. The stock is considered to be stable. Single-stock exploitation boundaries Exploitation boundaries in relation to precautionary limits/considerations The current fishery appears sustainable. Therefore, ICES recommends that Nephrops fisheries should not be allowed to increase relative to 2007. This corresponds to landings of no more than 1000 tonnes for the Eastern Irish Sea stock. Management considerations Landings by some fleets prior to 2007 are thought to have been underreported. The implementation of the Buyers and Sellers legislation in the UK in 2006 and “sales notes” in Ireland in 2007, coupled with the increased TAC in 2007, is thought to have improved the reliability of reported landings data. Therefore the advice for this stock refers to landings in 2007 only and does not use landings data prior to 2007. The Nephrops trawl fishery takes bycatches of other species, especially plaice but also cod. The management of these fisheries should be seen in the context of mixed fisheries. Young cod are known to occur in inshore areas in the Irish Sea. Future cod year classes should not be subjected to mortality as bycatch in smaller-mesh fisheries. Every effort should be made to eliminate bycatches of cod in Nephrops fisheries. Factors affecting the fisheries and the stock The effects of regulations The cod recovery measures introduced in 2000 includes closed areas and effort limitations. These regulations would have increased more directed effort at the Nephrops fisheries. The regulations included derogations for small-mesh trawlers and provided these trawlers with more favourable effort allocations. The fishery peaks in summer and with catch composition regulations in force along with other Nephrops fisheries peaking at different times, around 30 UK vessels temporarily relocated to the eastern coast of England in 2007 for the winter months. Changes in fishing technology and fishing patterns Effort has remained relatively stable over the last six years. Fuel prices have affected the choice of gears. Some twin trawl vessels in the Irish fleet have switched to single trawls in an effort to save on fuel. Despite reasonable catch rates some skippers are less inclined to put to sea unless they can guarantee to cover their costs. This would have contributed to the increase in annual lpues. Impacts of the environment on the fish stock There is no specific information of the impacts of the environment on this stock. Scientific basis Data and methods Information is currently inadequate for an analytical assessment of this stock and the status of spawning stock or exploitation rate cannot be evaluated. The evaluation of stock development was based on landings and effort information, length sample data from landings, catches and discards, mean sizes and sex ratio, and trends in lpue.


Information from the fishing industry A UK/Republic of Ireland self-sampling programme started in 2007 and is currently ongoing. This is a voluntary scheme involving vessels from the UK/ROI Nephrops fleet. Haul-by-haul catch and discard information is collected and samples of discards brought ashore for scientists to analyse. The scheme is still in its early stages and the time-series was insufficient to use in this assessment. Uncertainties in assessment and forecast There is insufficient data for a quantitative analytical assessment. Environment conditions No environmental data was used in this assessment. Comparison with previous assessment and advice In 2006 and 2008 the evaluation of Irish Sea east (FU 14) was based on trends in population indicators. The advice in 2006 for 2007 and 2008 was for Irish Sea east and Irish Sea west combined and was that effort in these fisheries should not be allowed to increase compared to 2003–2005 levels. The advice is now for Irish Sea east only and is similar in that effort in this fishery should not increase. Source of information Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 15–21 May 2008 (ICES CM 2008/ACOM:08).


Nephrops in Irish Sea East (FU14). Single stock exploitation boundaries (advice), management and landings.

Year ICES advice Advice for the Eastern

Irish Sea (FU14)

Recommended Landings

(FU14 +FU15)

Agreed TAC 1)


1989 0.4 1990 0.6 1991 0.9 1992 8.9 20.0 0.5 1993 9.4 20.0 0.6 1994 9.4 20.0 0.5 1995 9.4 20.0 0.6 1996 9.4 23.0 0.5 1997 9.4 23.0 0.6 1998 9.4 23.0 0.4 1999 9.4 23.0 0.6 2000 9.4 21.0 0.6 2001 9.4 18.9 0.5 2002 Set TAC in line with 1995–99 landings 9.55 17.79 0.6 2003 Set TAC in line with 1995–99 landings 9.55 17.79 0.4 2004 Set TAC in line with 1995–99 landings 9.55 17.45 0.5 2005 Set TAC in line with 1995–99 landings 9.55 19.544 0.6 2006 No increase in effort 9.55 21.498 0.6 2007 No increase in effort - 25.153 1.0 2008 As for 2007 - 25.153 - 2009 No increase in effort and landings (2007) <1.0 - -

Weights in ‘000 t. 1) Subarea VII. *Preliminary.



0

300

600

900

1200

1500

1960 1965 1970 1975 1980 1985 1990 1995 2000 2005

Land

ings

(ton

nes)

UK - Nephrops directed trawlersRep. of Ireland - Nephrops directed trawlersInternational

New reporting procedure

Effort - UK Nephrops trawlers

0

10

20

30

40

1960 1965 1970 1975 1980 1985 1990 1995 2000 2005

Effo

rt ('0

00 h

ours

traw

ling)

LPUE

0

10

20

30

40

50

60

1960 1965 1970 1975 1980 1985 1990 1995 2000 2005

LPU

E (k

g/ho

ur tr

awlin

g)

UK(NI) - Nephrops directed trawlersUK(E&W) - Nephrops directed trawlersUK - Nephrops directed trawlersROI - directed trawlers

New reporting procedure

Mean sizes - UK Nephrops trawlers

24

28

32

36

40

44

1960 1965 1970 1975 1980 1985 1990 1995 2000 2005

Mea

n si

ze (m

m c

arap

ace

leng

th)

Catch Mal < 35 mm CLCatch Fem < 35Landings Mal < 35Landings Fem < 35Landings Mal > 35Landings Fem > 35

Figure 5.4.34.1.1 Nephrops in Irish Sea East (FU 14). Long-term trends in landings, effort, cpues and/or lpues, and mean sizes.

Sex ratio

0

1

1

2

2

3

3

4

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Sex

Rat

io (M

ales

/Fem

ales

)

Figure 5.4.34.1.2 Nephrops in Irish Sea East (FU 14). Time-series of sex ratio in the landings of Nephrops-directed trawlers.


Table 5.4.34.1.1 Nephrops in Irish Sea East (FU 14). Landings (tonnes) by country, 1998-2007

Year Rep. of Ireland UK Other countries ** Total

1998 26 362 1 389 1999 153 471 0 625 2000 114 451 2 567 2001 26 506 0 532 2002 203 373 1 577 2003 69 306 1 376 2004 62 409 1 472 2005 34 536 0 570 2006 35 592 0 628

2007* 87 872 0 959

* provisional ** Other countries includes Belgium and Isle of Man


5.4.34.2 Nephrops in Irish Sea West (FU 15) State of the stock The trawl survey showed a peak in catch rates in 2003. The UWTV survey and the trawl survey show a declining trend in abundance after 2003. The trawl survey catch rate in 2007 was around the average of the time-series. Sex ratio and mean size from commercial catches and surveys remain stable. Single-stock exploitation boundaries Exploitation boundaries in relation to precautionary limits The current fishery appears sustainable. Therefore, ICES recommends that Nephrops fisheries should not be allowed to increase relative to 2007. This corresponds to landings of no more than 8500 tonnes for the Western Irish Sea stock. Management considerations Landings by some fleets prior to 2007 are thought to have been underreported. The implementation of the Buyers and Sellers legislation in the UK in 2006 and “sales notes” in Ireland in 2007, coupled with the increased TAC in 2007, is thought to have improved the reliability of reported landings data. Therefore the advice for this stock refers to landings in 2007 only and does not use landings data prior to 2007. The Nephrops trawl fisheries take bycatches of other species, especially juvenile whiting but also cod. Catches of these species should be reduced to as low as possible because of the poor status of these stocks. Factors affecting the fisheries and the stock The effects of regulations The cod recovery measures introduced in 2000 include closed areas and effort limitations. These regulations would have increased more directed effort at the Nephrops fisheries. The regulations included derogations for small-mesh trawlers with more favourable effort allocations. Changes in fishing technology and fishing patterns Fuel prices have had an effect on the fishing patterns in the Irish Sea in recent years and have affected the choice of gears. Some twin trawl vessels in the Irish fleet have switched to single trawls in an effort to save on fuel. A change in fishing practice in 2007 involved vessels migrating to North Sea grounds, resulting in reduced effort on Irish Sea fisheries. Separator trawls were introduced in the Ireland fishery in 2000 in an attempt to reduce cod bycatches. Impacts of the environment on the stock There is no evidence of an impact of the environment on this stock. Scientific basis Data and methods The evaluation is based on catch data from the fishery, a trawl survey from 1996, and a UWTV survey since 2003. The size structure of Nephrops in landings and discards is well sampled and a long time-series is available. Landings and effort data are available from commercial vessels targeting Nephrops. These data have not been corrected for changes in fishing power or efficiency over time. Information from the fishing industry The landings and discard length frequency data from commercial fisheries data were provided through a self-sampling scheme in Ireland and Northern Ireland.


Uncertainties in assessment and forecast The time-series of underwater TV surveys is short (2003–2007), but the observed abundance estimates in recent years are consistent with the August trawl survey. There are several uncertainties associated with the absolute abundance estimate from the UWTV survey. In this area burrow identification is a particular problem because of very high densities and turbidity in the water in some places. This may lead to an underestimate of abundance. Conversely, burrow occupancy and the accuracy of the area viewed may result in an overestimate of abundance. The lpue indicators are uncertain because the landings may have been underreported in the past and effective effort may have increased over time with increasing vessel efficiency. Comparison with previous assessment and advice The advice in 2006 for 2007 and 2008 was for Irish Sea east and Irish Sea west combined and was that effort in these fisheries should not be allowed to increase compared to 2003–2005 levels. In 2006 the advice was based on trends in the surveys and fisheries indicators, and this year the advice uses the same basis. Source of information Report of the Working Group on the Assessment of Northern Shelf Demersal Stocks, 15–21 May 2008 (ICES CM 2008/ACOM:08). Nephrops in Irish Sea West (FU 15). Single stock exploitation boundaries (advice), management and landings.

Year ICES advice Advice for the Western Irish Sea

(FU 15)

Recommended Landings

(FU14 + FU15)

Agreed TAC 1)


1989 8.1 1990 8.3 1991 9.6 1992 8.9 20.0 7.5 1993 9.4 20.0 8.1 1994 9.4 20.0 7.6 1995 9.4 20.0 7.8 1996 9.4 23.0 7.3 1997 9.4 23.0 10.0 1998 9.4 23.0 9.1 1999 9.4 23.0 10.8 2000 9.4 21.0 8.4 2001 9.4 18.9 7.4 2002 Set TAC in line with 1995–99 landings 9.55 17.79 6.9 2003 Set TAC in line with 1995–99 landings 9.55 17.79 7.1 2004 Set TAC in line with 1995–99 landings 9.55 17.45 7.4 2005 Set TAC in line with 1995–99 landings 9.55 19.544 6.5 2006 No increase in effort 9.55 21.498 7.6 2007 No increase in effort - 25.153 8.5 2008 No increase in effort - 25.153 2009 No increase in effort and landings < 8.5

Weights in ‘000 t. 1) Subarea VII.

ICES

Adv

ice

2008

, Boo

k 5

228

Land

ings

- In

tern

atio

nal

0

3000

6000

9000

1200

0

1500

0 1960

1965

1970

1975

1980

1985

1990

1995

2000

2005

Landings (tonnes)

Inte

rnat

iona

lUK

- A

ll gea

rsRe

p. o

f Ire

land

- A

ll gea

rs

Effo

rt -

Diff

eren

t fle

ets

050100

150

200

250 19

8019

8519

9019

9520

0020

05

Effort ('000 hours trawling)

UK N

orth

ern

Irela

nd N

ephr

ops

traw

lers

Rep.

of I

rela

nd

LPU

E -

Diff

eren

t fle

ets

0102030405060

1960

1965

1970

1975

1980

1985

1990

1995

2000

2005

CPUE or LPUE (kg/hour trawling)

Rep.

of I

rela

nd -

LPUE

UK N

orth

ern

Irela

nd -

LPUE

Mea

n si

zes

- Diff

eren

t fle

ets

2022242628303234

1960

1965

1970

1975

1980

1985

1990

1995

2000

2005

Mean size (mm carapace length)

ROI -

Cat

ch -

Mal

esRO

I - C

atch

- Fe

mal

esUK

NI -

Cat

ch -

Mal

UK N

I - C

atch

- Fe

m

Fi

gure

5.4

.34.

2.1

Nep

hrop

s in

Iris

h Se

a Ea

st (F

U 1

5). L

ong-

term

tren

ds in

land

ings

, eff

ort,

cpue

s and

/or l

pues

, and

mea

n si

zes o

f Nep

hrop

s.



Nephrops surveys: Mean catch per nm

0.0

20.0

40.0

60.0

80.0

100.0

120.0

140.0

1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

kg p

er n

m

Nephrops density from UWTV surveys

0.0

2.0

4.0

6.0

8.0

10.0

12.0

1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Abu

ndan

ce X

10

9

a )

b)

Figure 5.4.34.2.2 Nephrops in Irish Sea East (FU 15): a) Index of abundance from the joint Ireland and UK (NI)

UWTV survey; b) Index of abundance UK (NI) August trawl survey. Abundance is expressed as the number of individuals, but for the purpose of this advice, the figure is interpreted as relative abundance.


Table 5.4.34.2.1 Nephrops in Irish Sea West (FU 15). Landings (tonnes) by country, 1998-2007.

Year Rep. of Ireland Isle of Man UK Other countries Total

1998 3101 17 6027 0 9145 1999 4582 6 6198 0 10786 2000 3433 0 4937 0 8370 2001 2689 3 4749 0 7441 2002 2291 1 4501 0 6793 2003 2696 4 4352 0 7052 2004 2782 13 4470 1 7267 2005 2116 0 4412 0 6529 2006 2048 1 5502 1 7551

2007* 2736 0 5724 0 8461

* provisional


5.4.34.3 Nephrops on Porcupine Bank (FU 16)

State of the stock Effort in the Irish and French fleets has rapidly increased in the past four years. Landings per unit effort (lpue) information shows mixed signals, but with a generally declining trend in most fleets over the time-series available. Mean size indicators in all fleets and a survey indicate a large increase in mean size for both sexes in the past four years. Proxies for exploitation show an increase in exploitation in recent years and proxies for recruitment show very low recruitments since 2004. Landings have declined since the mid-1980s to a low point of the time-series in 2000, but have recently increased again. Single-stock exploitation boundaries Exploitation boundaries in relation to precautionary limits/considerations Because of the apparent low recruitment and the recent expansion of the fishery there is an associated increased exploitation. ICES recommends reduction in the exploitation rate and restricting catches in 2009 to no more than 1000 t, which corresponds to the catch level before the expansion of the fishery (2000–2003). The fishery should not be allowed to expand again unless it can be shown that it is sustainable. Management considerations Fishing effort directed at Nephrops will also have implications for the hake stock in the mixed fisheries unless species and size selectivity of gears can be improved. Factors affecting the fisheries and the stock Changes in fishing technology and fishing patterns The Nephrops fishery on the Porcupine Bank is both seasonal and opportunistic with increased targeting during periods of high Nephrops emergence and good weather. Effort has increased substantially for the Irish and French fleets in the fishery. Although Spanish effort has not increased there has been a large increase in lpues, indicating increased targeting of Nephrops. The increase in Irish effort is mainly due to increasing enforcement of anglerfish quotas and larger vessels switching to Nephrops fisheries. The increase in French effort may be associated with the closed area for cod in the Celtic Sea. Scientific basis Data and methods Annual landings length compositions for males and females are available from Spain (1986–2007), France (1995–2007), and Ireland (1995–2005). There are also length distributions and mean size data for the Spanish Porcupine Bank survey (2001–2007, Figure 5.4.35.2). Lpue and effort data are available for the Spanish, French, and Irish fleets (Figure 5.4.35.3). These data have been used to assess the state of the stock. Uncertainties in assessment and forecast Large differences are seen in the length compositions from different countries, which could indicate different selection patterns or different high grading practices between fleets. The combined landed length distributions are used to calculate the exploitation and recruitment proxies. Several uncertainties are associated with this approach, particularly as no length frequency data for Irish landings in the last two years and no discard data are available. The size distribution in fishery-independent surveys appears to confirm the weak recent recruitment. The recent increase in the exploitation proxy is coincident with an increase in effort and landings. There are concerns about the accuracy of the catch statistics and lpue information in some fleets. Growth rates cannot be well determined. Analytical assessments are not feasible at present. Comparison with previous assessment and advice The trends in effort and lpue are similar to the evaluation in 2006. However, mean size indicators and proxies for exploitation rate have now changed the perception of the stock compared to the evaluation in 2006.


The advice in 2006 was to constrain effort at recent levels. Because of the apparent declines in the stock, the advice now calls for a reduction in catches. Source of information Report of the Working Group on the Assessment of Southern Shelf Stocks of Hake, Monk, and Megrim, 30 April–7 May 2008 (ICES CM 2008/ACOM:12).

Table 5.4.34.3.1. Nephrops on Porcupine Bank (FU 16). Single stock exploitation boundaries (advice), management and landings.

Year ICES advice ICES advice for

Porcupine Bank

(FU16)

Recommended

Landings

VIIbcjk1

Agreed

TAC2

Official

Landings

(FU16)3

1987 2.5 1988 2.4 1989 2.1 1990 1.9 1991 1.6 1992 3.8 20.0 2.0 1993 ~4.0 20.0 1.9 1994 ~4.0 20.0 2.5 1995 ~4.0 20.0 2.9 1996 4.0 23.0 2.2 1997 4.0 23.0 2.4 1998 4.0 23.0 2.2 1999 4.0 23.0 2.1 2000 4.0 21.0 0.9 2001 4.0 18.9 1.2 2002 4.44 17.79 1.3 2003 4.44 17.79 0.9

2004 Restrict landings to 2000–2002 levels

3.3 17.45 1.4


3.3 19.5 2.1


3.3 21.4 1.9 2007 Constrain effort at recent levels -- 25.2 2.0 2008 Constrain effort at recent levels -- 25.2 2009 No increase in effort, and

average landings (2000-2003) < 1.0

Weights in ‘000t 1 Previously ICES gave combined advice for FUs 16, 17, 18, and 19, and Other rectangles in this area. 2 Subarea VII. 3 This includes inshore rectangles along the southern and southeastern coast of Ireland.


28

32

36

40

44

48

52

1980 1985 1990 1995 2000 2005

Mea

n si

ze (m

m c

arap

ace

leng

th)

Spain Landings Males Ireland Landings MalesFrance Landings Males Porcupine Survey Catch Males

28

32

36

40

44

1980 1985 1990 1995 2000 2005

Mea

n si

ze (m

m c

arap

ace

leng

th)

Spain Landings Females Ireland Landings FemalesFrance Landings Females Porcupine Survey Catch Females

Figure 5.4.34.3.1 Nephrops in FU 16 (Porcupine Bank). Landings in mean sizes by sex and country and in mean size in the catch for the Porcupine survey.


0

0.05

0.1

0.15

0.2

0.25

0.3

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

% n

umbe

rs fr

om L

FDs

Recruit Proxy <32mm

% >50mm CL

Figure 5.4.34.3.2 Nephrops FU 16 (Porcupine Bank). Trends in the percentages of the sampled male Nephrops landings <32 mm carapace length (a possible recruitment proxy) and >50 mm carapace length.

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

-slo

pe(ln

CL,ln

Nos

) (CL

s 41

-56) Exploitation Proxy

Figure 5.4.34.3.3 Nephrops FU 16 (Porcupine Bank). Trends in an exploitation proxy for this stock. This is derived from the slope of the length-frequency for male Nephrops between carapace lengths of 41–56 mm which are considered fully selected in the fishery.


Effort

0

10

20

30

40

50

1970 1975 1980 1985 1990 1995 2000 2005

Effo

rt '0

00hr

s

0

50

100

150

200

250

Effo

rt in

dex

France ('000 hrs traw ling)

Rep. of Ireland ('000 hrs traw ling)

Spain (effort index) (*)

LPUE

0

10

20

30

40

50

60

1982 1987 1992 1997 2002 2007

LPU

E kg

/hr

0

10

20

30

40

50

60

LPU

E in

dex

France (kg/hour traw ling)

Rep. of Ireland (kg/hour traw ling)

Spain - All Gears (kg/effort index) (*)

Figure 5.4.34.3.4 Nephrops FU 16 (Porcupine Bank). Effort and lpue trends for fleets.


Table 5.4.34.3.2 Porcupine Bank (FU 16). Landings (tonnes) by country, 1965–2007.

514 5140 0

441 441441 441609 609256 256500 1444 1944

0 1738 1738811 2135 2946900 1894 2794

0 2150 21506 1321 13270 1545 15452 1742 1744

14 2255 226921 2904 292566 3315 3381

358 3931 4289615 2811 34261067 2504 35711181 2738 39191060 1462 69 2591609 1677 213 2499600 1555 220 2375324 350 1417 24 2115336 169 1349 41 1895348 170 1021 101 1640665 311 822 217 2015799 206 752 100 1857

1088 512 809 103 25121234 971 579 152 29361069 508 471 182 22301028 653 473 255 2409879 598 405 273 2155889 609 448 185 2132313 227 213 120 872366 369 270 158 1163324 543 276 139 1282130 296 333 108 867232 494 588 126 1441380 741 799 208 2129446 732 571 192 1941297 1038 496 154 1985

UK

1996

Year France Rep. of Ireland

198419851986

1993

1969

20012002

Spain

1965196619671968

1995

1983

Total

197319741975

2003

1997199819992000

1994

1980

1970

2004

19811982

19911992

1987198819891990

20062005

2007

1979197819771976

19721971


5.4.34.4 Nephrops on Aran Grounds (FU 17) State of the stock Lpue indicators do not show signs of decrease in recent years. The UWTV survey conducted since 2002 estimates abundance to have fluctuated with a peak in 2004. The stock is considered to be stable. Single-stock exploitation boundaries Exploitation boundaries in relation to precautionary limits/considerations

The current fishery appears sustainable. Therefore, ICES recommends that Nephrops fisheries should not be allowed to increase relative to 2007. This corresponds to landings of no more than 900 tonnes for the Aran Grounds (FU 17).

Management considerations Landings by some fleets prior to 2007 are thought to have been underreported. The implementation of the Buyers and Sellers legislation in the UK in 2006 and “sales notes” in Ireland in 2007, coupled with the increased TAC in 2007, is thought to have improved the reliability of reported landings data. Therefore the advice for this stock refers to landings in 2007 only and does not use landings data prior to 2007. The advice is to constrain effort at recent levels. This should also take into account the efficiency and fishing pattern of vessels operating in the fishery which could result in an increase in effective effort. Nephrops fisheries in this area also have catches of megrim and monkfish. Factors affecting the fisheries and the stock Changes in fishing technology and fishing patterns There has been a substantial change in the fleet fishing this stock in 2007 with an increased number of vessels participating in the fishery, particularly in the autumn when the catchability in this area is high. In 2006 there has been an increase in the proportion of landings using a mesh size of 70 mm. Landings and effort of twin rig vessels has increased to over 90 % of the vessels in the fishery.. Scientific basis Data and methods Landings length compositions by sex are available for 1995–2000. Since 2001 a catch and discard sampling programme has been in place which shows some discarding of smaller individuals. Sampling in 2006 and 2007 stopped due to non-cooperation, but sampling has been resumed in 2008. Effort and lpue information from Irish Nephrops trawlers from 1995–2007 is used. Since 2002 there has been an annual UWTV survey which provides the fishery-independent information for this stock. Uncertainties in assessment Fleet composition has changed substantially due to fleet renewal and fleet decommission schemes which may impact the lpue series. There are concerns about the accuracy of the landings statistics. The estimates of the UWTV survey has shown large fluctuations. It is not known whether this reflects the fluctuations in stock abundance. Comparison with previous assessment and advice The assessment and advice is the same as that given previously.


Source of information Report of the Working Group on the Assessment of Southern Shelf Stocks of Hake, Monk, and Megrim, 30 April–7 May 2008 (ICES CM 2008/ACOM:12).

Nephrops on Aran Grounds (FU 17). Single stock exploitation boundaries (advice), management and landings.

Year ICES advice ICES advice for Aran Grounds (FU17)

Recommended TAC VIIbcjk1

Agreed TAC 2

ICES Landings (FU17)3

1987 0.1 1988 0.1 1989 0.8 1990 0.3 1991 0.5 1992 3.8 20.0 0.4 1993 ~4.0 20.0 0.4 1994 ~4.0 20.0 0.7 1995 ~4.0 20.0 0.9 1996 4.0 23.0 0.5 1997 4.0 23.0 0.8 1998 4.0 23.0 1.4 1999 4.0 23.0 1.1 2000 4.0 21.0 0.9 2001 4.0 18.9 0.9 2002 4.44 17.79 1.2 2003 4.44 17.79 0.9


3.3 17.45 0.5


3.3 19.5 0.8


3.3 21.4 0.6 2007 Constrain effort at recent levels -- 25.2 0.9 2008 Constrain effort at recent levels -- 25.2 2009 No increase in effort and landings

(2007) <0.9

Weights in ‘000t 1 Previously ICES gave combined advice for FUs 16, 17, 18, and 19, and Other rectangles in this area. 2 Subarea VII. 3 This includes inshore rectangles along the southern and southeastern coast of Ireland.


Figure 5.4.34.4.1 Nephrops in FU 17 (Aran Grounds). Irish effort and lpue for Nephrops-directed fleet.

0

5000

10000

15000

20000

25000

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

Effo

rt (h

rs)

0

10

20

30

40

50

60

70

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

LPU

E (K

g/hr

s)


Raised abundance estimate (million burrows)

0

500

1000

1500

2000

2500

2001 2002 2003 2004 2005 2006 2007 2008

Figure 5.4.34.4.2 Nephrops in FU 17 (Aran Grounds). Time-series of burrow abundance from the Irish underwater

TV survey (error bars indicate the geostatistical CV). For the purpose of this advice, the figure is interpreted as relative abundance.


Figure 5.4.34.4.1 Nephrops in FU 17 (Aran Grounds). Landings (tonnes) by country, 1965–2007.

Year France Rep. of Ireland UK Total

1974 477 4771975 822 8221976 131 1311977 272 2721978 481 4811979 452 4521980 442 4421981 414 4141982 210 2101983 131 1311984 324 3241985 207 2071986 147 1471987 62 621988 14 814 8281989 27 317 3441990 30 489 5191991 11 399 4101992 11 361 3721993 11 361 0 3721994 18 707 4 7291995 91 774 1 8661996 2 519 4 5251997 2 839 0 8411998 9 1401 0 14101999 0 1140 0 11402000 1 879 0 8802001 1 912 0 9132002 2 1152 0 11542003 0 925 0 9252004 0 525 0 5252005 0 772 0 7722006 0 631 0 6312007 0 931 0 931


5.4.34.5 Nephrops off the southeastern and southwestern coasts of Ireland (FU 19) State of the stock Landings have been variable throughout the time-series, reaching the highest observed levels in 2002–2004. Landings from 2005 onwards have been around average. Lpue has fluctuated without a detectable trend over the short time-series. Single-stock exploitation boundaries Exploitation boundaries in relation to precautionary limits/considerations The current fishery appears sustainable. Therefore, ICES recommends that Nephrops fisheries should not be allowed to increase relative to 2007. This corresponds to landings of no more than 800 tonnes for the Ireland SW and SE Coast (FU 19). Management considerations Landings by some fleets prior to 2007 are thought to have been underreported. The implementation of the Buyers and Sellers legislation in the UK in 2006 and “sales notes” in Ireland in 2007, coupled with the increased TAC in 2007, is thought to have improved the reliability of reported landings data. Therefore the advice for this stock refers to landings in 2007 only and does not use landings data prior to 2007. Nephrops fisheries in this area also catch megrim and anglerfish. There are also some catches of hake, and the offshore parts of the area are an important nursery area for juvenile hake. Factors affecting the fisheries and the stock Changes in fishing technology and fishing patterns The effort of Irish vessels fishing for Nephrops has increased since 2002. Since 2000 several new Irish vessels entered the fleet and some of these vessels now account for the majority of the landings. Regulations and their effects There has been increasing enforcement of anglerfish quota causing increased specialization in Nephrops. Scientific basis Data and methods Length–frequency data of the landings were collected on an irregular basis in the years 1996–1997, 1999, and 2002 to 2007. There is a slight increase in mean size for both sexes. However, the time-series is too short to provide useful information on the state of the stock (Figure 5.4.35.5.2). Lpue data are available for the Irish Nephrops fleet from 1995–2007 (Figure 5.4.35.5.1). These data have been used to assess the state of the stock. Uncertainties in assessment Changes in fleet composition due to fleet renewal and fleet decommissioning schemes may bias the lpue trends. .Spatial and temporal sampling coverage is problematic because landings from this area originate from several discrete grounds. No fisheries-independent data are available for this stock. Comparison with previous assessment and advice The assessment and advice is the same as that given previously. Source of information Report of the Working Group on the Assessment of Southern Shelf Stocks of Hake, Monk, and Megrim, 30 April–7 May 2008 (ICES CM 2008/ACOM:12).


Nephrops off the southeastern and southwestern coasts of Ireland (FU 19) Single stock exploitation boundaries (advice), management and landings.

Year ICES advice ICES advice for SW&SE Coast

of Ireland (FU19)

Recommended Landings VIIbcjk1

Agreed TAC 2

ICES Landings (FU19)3

1987 1988 1989 0.9 1990 0.8 1991 1.1 1992 3.8 20.0 0.9 1993 ~4.0 20.0 0.9 1994 ~4.0 20.0 0.4 1995 ~4.0 20.0 0.7 1996 4.0 23.0 0.9 1997 4.0 23.0 0.8 1998 4.0 23.0 0.8 1999 4.0 23.0 0.6 2000 4.0 21.0 0.7 2001 4.0 18.9 0.8 2002 4.44 17.79 1.3 2003 4.44 17.79 1.2 2004 Restrict landings to 2000–2002

levels 3.3 17.45

1.1 2005 Restrict landings to 2000–2002

levels 3.3 19.5

0.6 2006 Restrict landings to 2000–2002

levels 3.3 21.4

0.7 2007 Constrain effort at recent levels -- 25.2 0.8 2008 Constrain effort at recent levels -- 25.2 2009 No increase in effort and

landings (2007) <0.8

Weights in ‘000t 1 Previously ICES gave combined advice for FUs 16, 17, 18, and 19, and other rectangles in this area. 2 Subarea VII. 3 This includes inshore rectangles along the southern and southeastern coast of Ireland.


0

5

10

15

20

25

30

35

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

LPU

E (K

g/hr

s)

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

Effo

rt (h

rs)

Figure 5.4.34.5.1 Nephrops in FU 19 (Ireland SW and SE coasts). Trawl effort and lpue for Irish OTB vessels where

>30% of the landed weight was Nephrops.


25

30

35

40

45

1995 1997 1999 2001 2003 2005 2007

Mea

n si

ze (m

m c

arap

ace

leng

th)

Males Catches Females CatchesMales Landings <35mm Females Landings <35mmMales Landings <35mm Females Landings <35mm

Figure 5.4.34.5.2 Nephrops in FU 19 (Ireland SW and SE coasts). Mean size trends for catches and whole landings

by sex. Table 5.4.34.5.1 Nephrops in FU 19 (Ireland SW and SE coasts). Landings (tonnes) by country, 1989–2007.

1989 245 652 2 8991990 181 569 4 7541991 212 860 5 10771992 233 640 15 8881993 229 672 4 9051994 216 153 21 3901995 175 507 12 6951996 145 736 7 8881997 93 656 7 7561998 92 733 2 8271999 70 499 3 5722000 134 541 11 6862001 105 702 2 8092002 162 1130 0 12922003 151 1075 0 12262004 68 997 1 10662005 4 640 0 6442006 0 658 1 6592007 0 784 0 784

Year France Rep. of Ireland UK Total


5.4.34.6 Nephrops in Functional Units 20–22, Celtic Sea

State of the stock Landings have fluctuated around 4600 t since the mid-1990s. In 2006 and 2007 mean sizes in landings for the Irish and French fleets decreased consistent with higher recruitment in recent years. Lpue indicators do not show signs of decrease in recent years. The stock is considered to be stable. Single-stock exploitation boundaries Exploitation boundaries in relation to precautionary limits/considerations The current fishery appears sustainable. Therefore, ICES recommends that Nephrops fisheries should not be allowed to increase relative to 2007. This corresponds to landings of no more than 5300 tonnes for the Celtic Sea stock (FU20-22). Management considerations Landings by some fleets prior to 2007 are thought to have been underreported. The implementation of the Buyers and Sellers legislation in the UK in 2006 and “sales notes” in Ireland in 2007, coupled with the increased TAC in 2007, is thought to have improved the reliability of reported landings data. Therefore the advice for this stock refers to landings in 2007 only and does not use landings data prior to 2007. The advice is to constrain effort and landings at recent levels. This should also take into account the efficiency and fishing pattern of vessels operating in the fishery. Changes to these may result in an increase in effective effort. Nephrops occur in several discrete areas of muddy sediment and fisheries targeting different areas have very different size structures of catches. These fisheries also have differences in non-Nephrops bycatch composition (cod, whiting, and to a lesser extent haddock and hake). Discarding of small Nephrops is substantial. This shows that trawls currently used to target Nephrops are not technically adapted to select marketable Nephrops. Discarding of other fish species is also a problem in the Nephrops fishery. Factors affecting the fisheries and the stock The effects of regulations The minimum EU landing size (MLS) for Nephrops in this area is 8.5 cm of total size (25 mm CL), whereas French Producers’ Organizations adopted a specific regulation of 11.5 cm of total size (35 mm CL). This has led to discarding of Nephrops above the legal minimum landing size by the French fleet. The proportion of individuals landed as tails in French landings increased significantly over the recent period. These are mainly individuals below 35 mm (CL) which would have been discarded previously. Changes in fishing technology and fishing patterns The French effort has declined since 1995. Several old fishing vessels of the French fleet were replaced by newer ones, but the contribution of this change to the fishing pattern is unknown. The Irish fishing effort has increased, particularly in the most recent years. The French and Irish fleets have very different fishing patterns, with the specialized Irish fleet focusing on areas of high abundance of small Nephrops whereas the French fleet generally targets larger individuals in a more mixed fishery using a 100 mm mesh size. Impacts of the environment on the fish stock Nephrops occur in discrete patches where the sediment is suitable for them to construct their burrows. There is a larval phase where there may be some mixing with Nephrops from other areas depending on the oceanographic conditions, but the mechanisms for this in the Celtic Sea are not currently known. Cod has been identified as a predator of Nephrops in some areas, and the generally low level of the cod stock is likely to have resulted in reduced predation on Nephrops.


Scientific basis Data and methods The basic source of information is landings and lpue together with some information on the length distributions of the landings and catch. There is limited fishery-independent survey data. A new UWTV survey was initiated in 2006 and the results are expected to improve the information basis for this stock in the future. Some discard data are available from France (1985, 1991, and 1997) and Ireland (since 2002). The discards observations are insufficient to provide a full time-series of discards. Information from the fishing industry Meetings with representatives of the fishing industry were held in France and Ireland. The French industry underlined that the increase in the lpue series since the end of the 1990s might be ascribed to the change of the fishing efficiency of the fleet because some older vessels were replaced with new ones. In 2007 the Irish fishing industry noticed an increase in the abundance of small Nephrops on the “Smalls” fishing ground. Uncertainties in assessment and forecast The length distribution of the landings is part of the basis for this advice. The main uncertainty associated with this approach is related to the absence of discard data. The commercial effort data has not been corrected to take into account changing fishing power and fishing practices over time. The French trawl survey primarily focuses on demersal fish. The Nephrops catches in the 2007 survey were the highest observed over the 11-year time-series, but the catch rates for Nephrops in trawl surveys are highly variable and are not interpreted as an indicator for the stock. Comparison with previous assessment and advice The assessment and advice is similar to the advice provided in 2006. Indicators suggest that recruitment may have improved in recent years. Source of information Report of the Working Group on the Assessment of Southern Shelf Demersal Stocks, 30 April–6 May 2008 (ICES CM 2008/ACOM:12).


Nephrops in Functional Units 20–22, Celtic Sea. Single stock exploitation boundaries (advice), management and landings.

Year ICES advice ICES advice for the Celtic

Sea (FU20-22)

Recommended TAC for VIIg1)

and VIIh

Agreed TAC2

ICES landings (FU20-22)

1987 3.4 1988 3.2 1989 4.0 1990 4.3 1991 3.3 1992 ~3.8 20 4.2 1993 3.8 20 4.4 1994 3.8 20 4.9 1995 3.8 20 5.2 1996 3.8 23 4.6 1997 3.8 23 4.0 1998 3.8 23 3.8 1999 3.8 23 2.8 2000 3.8 21 4.6 2001 3.8 18.9 4.6 2002 3.8 17.79 4.6 2003 3.8 17.79 4.9

2004 Adjust TAC in line with landings of most recent 10 years

4.6 17.45 4.2

2005 Adjust TAC in line with landings of most recent 10 years

4.6 19.544 4.9

2006 Recent average landings 2000–2002 4.6 21.498 4.3 2007 No increase in effort - 25.153 5.3 2008 No increase in effort -- 25.153 2009 No increase in effort and landings (2007) <5.3

Weights in ‘000 t. 1) Excluding rectangles on the southern coast of Ireland (31E1, 32E1–2, 33E2–3) 2) Subarea VII.


0

2

4

6

8

10

12

14

16

18

20

1983

1985

1987

1989

1991

1993

1995

1997

1999

2001

2003

2005

2007

Year

Fren

ch L

PUE

(kg/

hr)

0

10

20

30

40

50

60

Iris

h LP

UE (k

g/hr

)

French LPUE kg/hrIrish LPUE kg/hr

0

50000

100000

150000

200000

250000

300000

1983

1985

1987

1989

1991

1993

1995

1997

1999

2001

2003

2005

2007

Year

Effo

rt (h

ours

fish

ed)

French Effort (hrs)Irish Effort (hrs)Total Effort (hrs)

Figure 5.4.34.6.1 Nephrops in FUs 20–22 (Celtic Sea). Lpue and fishing effort series for French (top) and Irish fleet

(bottom). The cpue indices are calculated by including discard sampling on-board or by a derivation method.


Table 5.4.34.6.1 Nephrops FUs 20–22 (Celtic Sea). Total and by country nominal landings (t) as used by ICES.

Year France Rep. of Ireland

UK Other Countries

Total reported

Unallocated Total

1983 3667 1984 3653 1985 3599 1986 2638 1987 3080 329 1988 2926 239 1989 3221 784 1990 3762 528 1991 2651 644 1992 3415 750 1993 3815 770 63 0 4648 -274 4374 1994 3658 1415 68 2 5143 -274 4869 1995 3803 1575 125 2 5505 -282 5223 1996 3363 1377 86 2 4828 -217 4611 1997 2589 1552 95 4 4240 -213 4027 1998 2241 1619 64 1 3925 -90 3835 1999 2036 824 41 0 2901 -78 2823 2000 2782 1793 47 1 4623 -44 4579 2001 2532 2123 21 1 4677 -33 4644 2002 3134 1496 15 8 4653 -50 4603 2003 3511 1385 19 N/A 4915 0 4915 2004 2511 1626 36 N/A 4173 0 4173 2005 2490 2389 53 N/A 4932 0 4932 2006 2398 1877 32 N/A 4307 0 4307 2007 2082 3226 47 6 5261 0 5261


5.4.35 Sole southwest of Ireland (Division VIIh–k)

Single-stock exploitation boundaries The new data available for this stock are too sparse to revise the advice given last year: “Catches should be no more than the recent average (2004–2006) of around 300 t, in order to avoid an expansion of the fishery until there is more information to facilitate an adequate assessment”. Source of information Report of the Working Group on the Assessment of Southern Shelf Demersal Stocks, 30 April–6 May 2008 (ICES CM 2008/ACOM:12). Year ICES

Advice



Predicted catch corresponding to

single-stock boundaries

Agreed TAC

ICES landings

1993 No advice - - 495 1994 No advice - - 398 1995 No advice - - 403 1996 No advice - - 443 1997 No advice - - 564 1998 No advice - - 423 1999 No advice - - 381 2000 No advice - - 329 2001 No advice - 650 325 2002 No advice - 650 430 2003 Reduce TAC to recent

landings 330 390

245 2004 1 Reduce TAC to recent average

(2000–2002) 1 360 390 290


335 650 326


380 650 272


287 650 277

2008 TAC < recent average (2004–2006)

300 650

2009 Same advice as last year

300



Table 5.4.35.1 Sole in Divisions VIIh–k (Southwest Ireland). Nominal landings (t), 1973–2006, as officially reported to ICES.

Country 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Belgium 406 369 210 638 519 290 384 522 576 471 411 Denmark - - - - - - - - - - France 390 143 207 19 103 23 29 27 107 104 176 Ireland 108 116 97 152 126 73 109 162 195 172 176 Netherlands 4 15 2 33 140 60 - - 51 Spain 190 153 152 131 26 1 8 2 38 UK - E W NI . . . . . . . . . . . UK - E W 6 5 24 11 12 11 18 42 83 108 129 UK - Scotland - - - - - - - - - - - Total 1104 801 692 984 926 458 548 755 961 855 981 Country 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 Belgium 474 318 442 271 254 252 353 358 312 317 338 433 Denmark - - - - - - - - - - - - France 120 25 38 44 53 84 66 55 43 44 42 47 Ireland 156 201 188 168 182 206 266 306 255 237 184 243 Netherlands 194 280 3 - - - - - - - - Spain - - - - - - - - UK - E W NI . . . . . 177 144 234 215 209 172 192 UK - E W 151 200 261 193 166 . . . . . . . UK - Scotland - - - - - - - - 2 5 2 - Total 1095 1024 932 676 655 719 829 953 827 812 738 915 Country 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 Belgium 375 368 346 101 8 13 154 170 157 90 36 31 Denmark - - - - - - - - - . France 50 58 74 . 79 103 108 138 108 99 92 69 Ireland 183 203 221 207 111 125 130 105 111 98 63 74 Netherlands 70 - 7 1 10 - - - - . 1 Spain - - - - - - 1 - - 2 UK - E W NI 148 113 111 97 95 111 124 78 79 112 UK - E W . . . . . . . . . . UK - Scotland - - - - - - - - - . UK 87 91 Total 826 742 759 406 303 352 517 491 455 401 279 265 Unallocated -383 -178 -336 -25 26 -27 -87 -246 -165 -75 -7 12 WG estimate 443 564 423 381 329 325 430 245 290 326 272 277


5.4.36 Sole west of Ireland (Divisions VIIb,c)

Single-stock exploitation boundaries The new landings, cpue, and survey data available for this stock do not change the perception of the stock and do not give reason to change the advice from 2007. The advice on this stock for the fishery in 2009 is therefore the same as the advice given in 2007 for the 2008 fishery: “Catches should be no more than the recent average (2004–2006) of around 50 t, in order to avoid an expansion of the fishery until there is more information to facilitate an adequate assessment.” Source of information Report of the Working Group on the Assessment of Southern Shelf Demersal Stocks, 30 April–6 May 2008 (ICES CM 2008/ACOM:12). Year ICES

Advice



to advice

Predicted catch corresponding to single-stock

boundaries

AgreedTAC

ICES landings

1993 - - - 60 1994 - - - 70 1995 - - - 59 1996 - - - 57 1997 - - - 55 1998 - - - 66 1999 - - - 72 2000 - - - 57 2001 - - 80 60 2002 No advice - 80 61 2003 Reduce TAC to recent

landings 65 80 64

2004 1 Reduce TAC to recent landings (1998–2002)

1 65 65 69

2005 Reduce TAC to recent landings (1999–2003)

62 65 44

2006 No increase in catches 64 65 43 2007 No increase in catches 64 65 41 2008 No increase in catches 50 59 2009 Same advice as last year 50 Weights in t. 1 Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits.


Table 5.4.36.1 Sole in Divisions VII b, c (Southwest Ireland). Nominal landings (t), 1973–2006, as officially reported to ICES.

Country 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 France - 25 7 6 3 3 6 9 6 5 9 3 Ireland 12 12 19 44 14 16 13 24 47 55 40 17 Spain 19 16 30 25 1 - 11 1 - - - - UK - E W NI . . . . . . . . . . . . UK - E W - - - - - - - - - 1 - - Total 31 53 56 75 18 19 30 34 53 61 49 20 Country 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 France 6 8 2 2 - - 5 2 1 1 2 2 Ireland 44 29 39 34 38 41 46 43 59 60 59 52 Spain - - - - - - - - - - - - UK - E W NI . . . . - - - - - - - - UK - E W - - - 1 . . . . . . . . Total 50 37 41 37 38 41 51 45 60 61 61 54 Unallocated 0 9 -2 3 WG Estimate 60 70 59 57 Country 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 France 3 - . 13 11 14 24 24 13 12 6 Ireland 51 49 68 65 53 50 50 49 38 31 34 Spain - - - - - - - - . . UK - E W NI 1 - - - - - - - . . UK - E W . . . . . . . . . . Total 55 49 68 78 64 64 74 73 51 43 40 Unallocated 0 17 4 -10 -4 -3 -10 -4 -7 0 1 WG Estimate 55 66 72 68 60 61 64 69 44 43 41


5.4.37 Demersal elasmobranchs in the Celtic Seas (ICES Areas VI, VIIa–c, e–k) State of the stocks In the absence of defined reference points, the status of the stocks of demersal skates and rays and demersal sharks can-not be evaluated. The following provides a qualitative summary of the general status of the major species based on sur-vey and landings data. Landings of skates and rays in the Celtic Seas have generally declined (Figure 5.4.39.1). There have been regional changes in species composition and indices of relative abundance. Species Scientific name Area1 State of stock

VI Common skate Dipturus batis VII Depleted

VIa Thornback ray Raja clavata VIIa,f,g Stable/increasing

VIa Spotted ray Raja montagui VIIa,f,g Stable/increasing

VIa Stable/increasing Cuckoo ray Leucoraja naevus VII Uncertain

Blonde ray Raja brachyura VIa, VIIa and VIIf Uncertain

Undulate ray Raja undulata VIIj (Tralee Bay) and VIIde Uncertain (but with cause for concern)

Smalleyed ray Raja microocellata VIIf Stable/increasing VI Uncertain Sandy ray Leucoraja circularis VIIb,c,h–k Stable/increasing

Shagreen ray Leucoraja fullonica VII Uncertain White skate Rostroraja alba VII Severely depleted Lesser spotted dogfish Scyliorhinus canicula VIa and VII Stable/increasing Greater spotted dogfish Scyliorhinus stellaris VII Locally stable and increasing in VIIa

Smooth hounds Mustelus mustelus and Mustelus asterias VII Stable/Increasing

Angel shark Squatina squatina VII Severely depleted 1 There is insufficient information to assess the status of stocks in the Rockall area (Division VIb). Skates and rays Common skate Depleted. It was formerly widely distributed in the Irish Sea (VIIa), but is now rarely found in this

division. Now mostly found off Northwest Scotland (VIa), west of Ireland (VIIb,c), and in the deeper waters of the Celtic Sea (VIIg–j), with occasional individuals in shallower areas (VIIe–f).

Thornback ray Stable/increasing. Catches in the main areas of abundance (VIa, VIIa,f,g) have been stable/increasing

in recent years (Figures 5.4.39.2 and 5.4.39.3). Spotted ray Stable/increasing. Catches in the main areas of abundance (VIa, VIIa,f,g) have been stable/increasing

in recent years (Figures 5.4.39.4 and 5.4.39.5). Cuckoo ray Uncertain and more robust studies on stock identity are required. Data from surveys give contrasting

signals (Figures 5.4.39.6, 5.4.39.7, and 5.4.39.8), showing stable/increasing catches in VIa, but stable or declining catches within Subarea VII. French lpue in the Celtic Sea is also declining (Figure 5.4.39.9).

Blonde ray Uncertain. This species has a patchy distribution in the Celtic Seas ecoregion, so interpretation of sur-

vey trends is problematic. Undulate ray Uncertain. Given that this large-bodied species has a patchy distribution in the inshore waters of the

Celtic Seas ecoregion, it is susceptible to localized over-exploitation. Smalleyed ray Stable/increasing. Catches in the main area of the stock distribution (VIIf) have been stable/increasing

over the survey time-series (Figure 5.4.39.10).


Sandy ray Uncertain. This offshore species is not well sampled in most groundfish surveys. Catches on the Por-

cupine Bank have been stable/increasing in recent years (Figure 5.4.39.11). Shagreen ray Uncertain. This offshore species is not well sampled in most groundfish surveys. White skate Severely depleted and possibly extirpated from most parts of this ecoregion. No authenticated records

in recent groundfish surveys. Demersal sharks Lesser spotted dogfish – Stable/increasing in all areas (Figures 5.4.39.12, 5.4.39.13, and 5.4.39.14). Greater spotted dogfish – Stable/increasing in localized areas (e.g. off Northwest Wales) (Figure 5.4.39.15), but not

well sampled by existing surveys, as it prefers rocky, inshore grounds, which are not sampled effec-tively in most surveys.

Smoothhounds Abundance seems to have been increasing in recent years both in survey catches (Figure 5.4.39.16)

and in commercial/recreational fisheries, but the stock status is very uncertain. Identification by spe-cies is considered unreliable in the surveys.

Angel shark Severely depleted and possibly extirpated from parts of its former range where it was once common,

including Start Bay (VIIe) and Cardigan Bay (VIIa). Management objectives Management objectives have not been adopted. An European sharks action plan was published by the European Com-mission in December 2007 and went out for consultation in 2008. Reference points Not defined. Single-stock exploitation boundaries No fisheries – Species where indicators show extirpation

White skate – has a localized and patchy distribution, and is extirpated from most parts of the Celtic Seas ecore-gion. It should receive the highest possible protection. Any incidental bycatch should not be landed, but returned, to the sea, as they are likely to have a high survival rate. Angel shark – has a localized and patchy distribution, and is extirpated from parts of its former range. It should receive the highest possible protection. Any incidental bycatch should not be landed, but returned, to the sea, as they are likely to have a high survival rate.

No target fisheries – Species where indicators show depletion (or may be susceptible to local depletion)

Common skate – has declined in many inshore areas of England and Wales, although is still present in the in-shore areas of Scotland and Ireland. Target fisheries for this species should not be permitted and measures should be taken to minimize bycatch. Undulate ray – has a patchy distribution, with some of these areas showing signs of depletion. As a precautionary measure, target fisheries for this species should not be permitted unless exploitation rates are shown to be sus-tainable.

Status quo catch – Species where indicators show recent stability or increase

Thornback ray, spotted ray in VIa and VIIa,f,g. and cuckoo ray in VIa. Smalleyed ray in VIIf – has a restricted distribution and is locally abundant in the Bristol Channel, this stock should be monitored to ensure that it does not decline.


Lesser spotted dogfish – the current exploitation rates appear to be sustainable. As there are no apparent detri-mental impacts on the stock from current commercial fisheries, no management actions are required for this spe-cies at this time. Greater spotted dogfish –has a restricted distribution and is locally abundant in parts of the Celtic Seas ecoregion, and should be monitored appropriately. Smoothhounds –have a relatively higher productivity than similar elasmobranchs and can probably sustain fish-eries. Management measures should prevent overexploitation. Fisheries should only expand when accompanying measures lead to improved data collection and biological studies to ensure its sustainable harvest.

No advice – Species where indicators are unknown

Cuckoo ray in VII – Further studies to better understand stock structure are required, although this species is one of the more abundant skates in the Celtic Seas ecoregion. Blonde ray – is widely distributed in the Celtic Seas ecoregion, but it has a tendency to form local aggregations and so may be prone to localized depletions. Sandy ray – most abundant on the outer continental shelf and upper continental slope, it is not well sampled in most existing groundfish surveys. Shagreen ray – most abundant on the outer continental shelf and upper continental slope, it is not well sampled in most existing groundfish surveys.

Management considerations Celtic Seas demersal elasmobranchs are normally landed as a bycatch in the demersal fisheries for teleosts, with local-ized targeted fisheries. They are usually landed and/or reported in mixed categories such as “skates and rays” and “sharks”. Landings of skates and rays should be declared at species level for all species. For assessment purposes spe-cies-specific landings data are essential. In most countries skates and rays are landed together, most often sorted in particular size categories, rather than by spe-cies. They are usually gutted, and sometimes only wings are landed. Only some countries report (part of) the landings by species, i.e. France, Belgium, and Spain (Basque country). There is currently no TAC for skates and rays in the Celtic Seas. The introduction of TACs can only regulate the land-ings, and any TAC on a bycatch species may induce more discards. Mesh-size regulations are probably not restrictive as there are few directed fisheries for these species. Certain elasmobranch species such as lesser spotted dogfish are pri-marily a bycatch species and are normally discarded. Discard survivorship of skates and rays is not known. Survivor-ship of coastal, demersal catsharks (Scyliorhinus spp.) is considered high. Elasmobranchs are typically slow growing, have a high age-at-maturity and a low reproductive capacity. Measures to afford protection to the larger species are required. Historically, angel shark and white skate have been common locally in some inshore areas of the Celtic Seas ecoregion. Neither species has been recorded during recent groundfish surveys. Landings data for angel shark have declined to near-zero. The extirpation of these large-bodied, inshore elasmobranchs that have patchy distributions is a cause of concern, because there may be a low rate of population growth and low level of immigration from adjacent areas. Both species are likely to be equally threatened in more southerly European seas. This represents a potential loss in the fish diversity in the ICES area. Impact of fisheries in the ecosystem Skates and rays, and demersal sharks are widely spread throughout the Celtic Seas. They are mostly caught in mixed fisheries for gadoids and flatfish such as plaice and sole. Due to their life history characteristics they are usually very susceptible to fisheries. Larger elasmobranchs such as common skate, white skate, and angel shark are particularly vul-nerable and have become locally depleted or extirpated. Scientific basis Data and methods Survey data are the basis for the assessments of skates, rays, and demersal sharks in the Celtic Seas (see ICES, 2007, 2008).


Uncertainties in assessment and forecast Survey data are the most reliable species-specific data available for demersal skates. However, many of the fishery-independent surveys in this ecoregion are not based on extensive time-series. These surveys are designed primarily for other types of fish and so the gears and sampling grids are not ideal for skate stocks, especially those species with patchy distributions. Comparison with previous assessment and advice ICES has never provided advice on these elasmobranchs in this area. Source of information ICES. 2007. Report of the Working Group on Elasmobranch Fishes (WGEF), 22–28 June 2007, Galway, Ireland. ICES CM 2007/ACFM:27, 318 pp. ICES. 2008. Report of the Working Group on Elasmobranch Fishes (WGEF). 3–6 March 2008, ICES Headquarters. ICES CM 2008/ACOM:16.


Skates and rays

Year ICES Advice

Single-stock ex-ploitation boundaries

Predicted catch corre-sponding to advice

Predicted catch cor-responding to single-stock ex-ploitation boundaries

Agreed TAC (1)

ACOM landings

Disc. slip.

ICES Catch

1992 No advice No TAC 16.6 1993 No advice No TAC 14.5 1994 No advice No TAC 13.9 1995 No advice No TAC 15.3 1996 No advice No TAC 19.0 1997 No advice No TAC 20.5 1998 No advice No TAC 20.0 1999 No advice No TAC 19.9 2000 No advice No TAC 19.9 2001 No advice No TAC 17.8 2002 No advice No TAC 18.8 2003 No advice No TAC 17.6 2004 No advice No TAC 13.2 2005 No advice No TAC 13.0 2006 No advice No TAC 10.0 2007 No advice No TAC 7.9 (2) 2008 No advice No TAC 2009 Various (3) NA NA

Weights in ‘000 t. (1) EU only. (2) Incomplete data. Landings are expected to be ~9000 tonnes. (3) If landings of major species recorded by species. With zero catch of common skate, white skate and angel shark, and no targeted fishery for undulate ray.


Figure 5.4.37.1 Rays and skates: landings in the Celtic Seas a) by country and b) by ICES area. All species com-bined, from ICES (2008). Data for 2007 are preliminary.

b)

Celtic Seas Ray landings

0

5000

10000

15000

20000

25000

1973

1975

1977

1979

1981

1983

1985

1987

1989

1991

1993

1995

1997

1999

2001

2003

2005

2007

Year

Tota

l lan

ding

s (to

nnes

) OthersUK – ScotlandUK - (E,W&N.I.)SpainIrelandFranceBelgium

Ray landings in the Celtic Seas

0

5000

10000

15000

20000

25000

1973

1975

1977

1979

1981

1983

1985

1987

1989

1991

1993

1995

1997

1999

2001

2003

2005

2007

Year

Land

ings

(ton

nes) VIIbcjk

VIIeghVIIf

VIIaVIbVIa

a)

b)


Figure 5.4.37.2 Thornback ray in Division VIa. Estimated year effects from the GAM analysis of Scottish survey catch rate data (log scale). Models are for N/hr.

Figure 5.4.37.3 Thornback ray in the Irish Sea (VIIa) and Bristol Channel (VIIf). Mean catch rates of from the UK 4 m beam trawl survey (1993–2007). Smoothed line is the three-year moving average.

(f) Raja clavata

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

Year

Mea

n C

PU

E (N

o/h)


Figure 5.4.37.4 Spotted ray in Division VIa. Estimated year effects from the GAM analysis of Scottish survey catch rate data (log scale). Models are for N/hr.

Figure 5.4.37.5 Spotted ray in the Irish Sea (VIIa) and Bristol Channel (VIIf). Mean catch rates from the UK 4 m beam trawl survey (1993–2007). Smoothed line is the three-year moving average.

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

Year

Mea

n C

PU

E (N

o/h)


Figure 5.4.37.6 Cuckoo ray on the Porcupine Bank. Biomass index from the Porcupine Survey (2001–2007). Boxes indicate the parametric standard error of the stratified biomass index. Lines mark bootstrap confidence intervals (α = 0.80, bootstrap iterations = 1000).

Figure 5.4.37.7 Cuckoo ray in Division VIa. Estimated year effects from the GAM analysis of Scottish survey catch rate data (log scale). Models are for N/hr.

Survey

Yst

(kg/

haul

)

0.0

0.5

1.0

1.5

P01

P02

P03

P04

P05 P06

P07

10 %

90 %


Figure 5.4.37.8 Cuckoo ray in the Irish Sea (VIIa) and Bristol Channel (VIIf). Mean catch rates in the UK 4 m

beam trawl survey (1993–2007). Smoothed line is the three-year moving average. Data for cuckoo ray use trawl stations from the central Irish Sea/St George’s Channel.

Figure 5.4.37.9 Cuckoo ray in the Celtic Sea (VIIgh). Lpue of French trawlers targeting benthic species (anglerfish, megrim, and rays). Data from 2000 onwards are from logbooks only.

LPUE

01

234

56789

10

1985

1987

1989

1991

1993

1995

1997

1999

2001

2003

2005

2007

(kg/

hour

)

(g) Leucoraja naevus

0.01.02.03.04.05.06.07.0

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

Year

Mea

n C

PUE

(No/

h)


Figure 5.4.37.10 Smalleyed ray in the Irish Sea (VIIa) and Bristol Channel (VIIf). Mean catch rates in the UK 4 m beam trawl survey (1993–2007). Smoothed line is the three-year moving average. Data use trawl stations from the Bristol Channel only.

Figure 5.4.37.11 Sandy ray on the Porcupine Bank. Biomass index from the Porcupine Survey (2001–2007). Boxes indicate the parametric standard error of the stratified biomass index. Lines mark bootstrap confidence intervals (α = 0.80, bootstrap iterations = 1000).

Survey

Yst

(kg/

haul

)

0 .0

0.5

1.0

1.5

2.0

P01

P02

P03

P04

P05

P06

P07

10 %

90 %

(h) Raja microocellata

0.0

1.0

2.0

3.0

4.0

5.0

6.0

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

Year

Mea

n C

PUE

(No/

h)


Figure 5.4.37.12 Lesser spotted dogfish on the Porcupine Bank. Biomass index from the Porcupine Survey (2001–2007). Boxes indicate the parametric standard error of the stratified biomass index. Lines mark bootstrap confidence intervals (α = 0.80, bootstrap iterations = 1000).

Figure 5.4.37.13 Lesser spotted dogfish in Division VIa. Estimated year effects from the GAM analysis of Scottish survey catch rate data (log scale). Models are forN/hr.

Survey

Yst

(kg/

haul

)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

P01

P02

P03

P04

P05 P06

P07

1 0 %

9 0 %


Figure 5.4.37.14 Lesser spotted dogfish in the Irish Sea (VIIa) and Bristol Channel (VIIf). Mean catch rates from the

UK 4 m beam trawl survey in the Irish Sea and Bristol Channel (1993–2007). Smoothed line is the three-year moving average.

Figure 5.4.37.15 Greater spotted dogfish in the Irish Sea (VIIa) and Bristol Channel (VIIf). Mean catch rates from the UK 4 m beam trawl survey in the Irish Sea and Bristol Channel (1993–2007). Smoothed line is the three-year moving average.

Figure 5.4.37.16 Smoothhounds in the Irish Sea (VIIa) and Bristol Channel (VIIf). Mean catch rates from the UK 4 m beam trawl survey in the Irish Sea and Bristol Channel (1993–2007). Smoothed line is the three-year moving average.

05

1015202530354045

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

Year

Mea

n C

PU

E (n

o/h)

(c) Mustelus spp.

0.00.51.01.52.02.53.03.5

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

Year

Mea

n C

PU

E (n

o/h)

0.0

0.1

0.2

0.3

0.4

0.5

0.6

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

Year

Mea

n C

PU

E (n

o/h)

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