Descriptor 3Descriptor 3Fishery indicators V.Raykov,IO-BAS

Five main steps were identified to assess Good Environmental Status GES for D3:• Selection of commercially exploited (shell)fish populations relevant to theMSFD (sub)region, or MS-specific sub-division, being assessed with respectto D3;• Identification of stocks that can be assessed in relation to the primary assessmentcriteria for D3.1 and D3.2;• Determination of criteria to apply to stocks that can not be assessed in relationto the primary assessment criteria, and identification of stocks thatcan be assessed according to these secondary criteria;• Interpretation of how to define GES for D3 with respect to combining individualstock assessments at the criteria level, and how to combine criterialevel assessments at the descriptor level;• Assessment of current status in relation to GES.

The ChoiceThe Choice(1) Identification of the

appropriate area; (2) Match of existing spatial

units to that area; (3) Choice of datasource; (4) Choice of time period; (5) Selection criteria.

AssessmentAssessment (1) all indicators with reference levels, (2) not all reference levels, or (3) no

reference levels. For commercial populations that do not have full

assessments scientific monitoring surveys were identified as a potential data source for

calculating some secondary indicators. Three options for determining the current status from trend-

based time series were considered: (1) comparing the recent period mean with

the long-term average (2) comparing the current value of the indicator in relation to

the historic mean setting a threshold based on appropriate percentile of the

Normal distribution; (3) detection of trends.

GESGES GES Interpretation 1: strict interpretation of the

Commission Decision where MSY reference levels are treated as a limit

and thus all stocks must meet the MSY requirement • GES Interpretation 2: the MSY reference levels

are considered as a target and thus half the stocks must achieve the MSY

requirement, and all stocks must achieve precautionary reference levels • GES Interpretation 3: the MSY reference levels

are considered as a target and stocks need to achieve this requirement on

average. This average is calculated accounting for the ‘distance’

individual stocks are above or below the MSY reference level.

For the overall assessmentFor the overall assessmentof Descriptor 3, three approaches were of Descriptor 3, three approaches were considered in the case studies: (1) noconsidered in the case studies: (1) noaggregation across criteria; (2) application of aggregation across criteria; (2) application of the one-out-all-out aggregation rule orthe one-out-all-out aggregation rule or“assessment by worst case”; or (3) application “assessment by worst case”; or (3) application of weights for the different criteria.of weights for the different criteria.

A higher proportion of assessed stocks increases the quality of the GES assessment;species/taxa for which no information is available decreases the quality;length of the time-series (with/without Reference levels);

Stocks for which analyticalstock assessments are conducted the populations

for which only information from monitoring programs is available.

F, SSB

‘catch/biomass ratio’;Biomass indices

Proportion of fish larger than the mean size of first sexual maturationMean maximum length across all species found in research vessel surveys95% percentile of the fish length distribution observed in research vessel surveys

Size at first sexual maturation, whichmay reflect the extent of undesirable genetic effects of exploitation

Issues to be consideredIssues to be consideredAppropriate areas –

divisions/subdivisions?The time period over which the

landings data are considered determines the relative importance of species or species groups;

Threshold for inclusion of species – 1% but in Baltic Sea 0.5% as a threshold for salmon – important but with low catches;

Member States shall, when implementing their obligations under this Directive, take due

account of the fact that marine waters covered by their sovereignty or jurisdiction form an integral

part of the following marine regions:(a) the Baltic Sea;(b) the North-east Atlantic Ocean;(c) the Mediterranean Sea;(d) the Black Sea.

Fishing mortalityFishing mortality

Fmsy,Fmax,F0.1Fmsy,Fmax,F0.1

Based on single species analysis (without ecosystem considerations; Predator-prey relationship);

SSB – single stock estimatinsSSB – single stock estimatins

Species covered by Species covered by monitoring programsmonitoring programs

What is GES?What is GES?

Indicators calculationIndicators calculation

Black SeaBlack SeaIndicator calculations for BG waters

Видове 2006 2007 2008 2009 2010 2011 Mean catch %

Трицона (Sprattus sprattus)2654.7

52984.5

94309.4

34551.3

24041.3

83957.9

0 3749.89 48.54

Рапани (Rapanа spp.)2773.1

84309.9

92871.5

52213.9

44830.9

13118.8

7 3353.07 43.40

Сафрид (Trachurus mediterraneus ) 62.83 115.89 179.92 176.91 165.27 394.84 182.61 2.36

Барбуня (Mullus barbatus ) 6.11 12.60 16.64 48.19 72.40 176.20 55.36 0.72

Сем. Попчета (Gobiidae) 31.34 73.89 25.66 36.82 44.24 85.18 49.52 0.64

Морска лисица (Raja clavata) 3.56 25.58 46.81 72.21 93.43 48.32 0.52

Калкан (Scophtalmus maximus) 14.81 66.89 54.87 52.47 46.45 38.06 45.59 0.59

Черноморска бодлива акула (Squalus acanthias) 6.23 23.98 22.75 9.46 77.16 81.01 36.76 0.48

Хамсия (Engraulis encrasicholus ) 6.46 60.44 28.03 42.41 64.73 18.11 36.70 0.47

Карагьоз, дунавска скумрия (Alosa immaculata) 17.72 25.81 27.48 37.38 59.08 51.80 36.54 0.47

Лефер (Pomatomus saltatrix) 8.46 8.22 25.18 52.54 63.49 29.39 31.21 0.40

other 47.52 145.48 78.51 126.27 148.58 102.82 115.86 1.40

Общо5629.4

17831.3

37665.6

07394.5

39685.8

88147.6

1

Biomass from scientific surveys

Catch, Fishing mortality

Daskalov et al., 2012

Catch and biomass - TACsНационални данни,

трицона 2008 2009 2010 2011

Квота, т 15 000** 12 750** 12 750** 8032.51 114751*

Общ улов, т 4 300.0363 4 541.35 4 039.966 3 957.90

Биомаса, т 32 718.3 41 761.398 75 080.20**** 48201.7

Национални данни, калкан 2008 2009 2010 2011

Квота, т 50* 50* 46* 43.2*

Общ улов, т 54. 7094 52. 07445 46.24314 38.03

Биомаса, т 1 966.18 1555.94 633.120 355.65

Catch/Biomass ratio

Калкан Година Индекс на

биомасата (т) Улов (т)

Съотношение улов/биомаса

2006 1441.06 14.81 0.010 2007 1837.66 66.89 0.036 2008 1 966.18 54.87 0.028 2009 1555.94 52.47 0.034 2010 633.12 46.45 0.073 2011 355.65 38.03 0.107

Трицона Година Индекс на

биомасата (т) Улов (т)

Съотношение улов/биомаса

2007 29190 2984.59 0.102 2008 32718.3 4309.43 0.132 2009 41761.4 4551.32 0.109 2010 75080.2 4041.38 0.054 2011 48201.7 3938.53 0.082

Trends

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

2005 2006 2007 2008 2009 2010 2011 2012

Съ

отно

шен

ие у

лов/

биом

аса

Калкан Трицона

Lmax (mean values) across all species caught in surveys

year No of species (S) L max zone

2012 8.6 21.00 coastal

2012 6.33 22.96 shelf

95% Percentile from L

species year percentile

95% Mean

lenght,cm min max SD CI (95%) zone

Whiting 2012 14.08 10.89 6.00 17.70 1.42 0.01

Sprat 2012 10.23 8.38 6.80 11.20 1.09 0.01

N.mel. 2012 14.11 11.28 6.00 17.70 1.70 0.28

Bluefish 2012 12.91 11.49 9.00 13.50 1.12 0.01

R.mullet 2012 12.60 9.37 5.00 14.40 1.62 0.01

H.mackerel 2012 13.20 9.58 5.50 14.50 2.06 0.01

Coastal

Turbot 2006 62.90 44.81 26.00 76.50 9.94 1.69

2007 58.48 46.19 26.50 74.00 6.77 0.70

2008 57.00 46.28 15.00 71.00 9.26 0.92

2009 63.00 50.92 24.00 74.00 7.55 0.76

2010 67.25 52.44 15.00 73.00 12.18 2.11

2011 65.75 44.34 10.00 68.00 15.72 3.72

Sprat 2012 10.08 8.22 6.00 11.50 1.37 0.01

Whiting 2012 13.92 10.91 5.90 17.00 1.50 0.01

N.melanos 2012 14.36 11.73 6.00 17.00 1.39 0.01

R.mullet 2012 13.03 10.96 9.50 17.00 1.21 0.02

Shelf

Sprat and Sprat and turbotturbotLmean Reference level for the given period of

“healthy stock” conditionHolt (1958), Lopt – which assure max Y/R

if all specimen were caught at the Lopt.Froese et al. (2008) - Yield of the individuals

reached Lopt, won’t affect negatively age structure of the population;

Froese and Sampang (2012) – the stock will have proportion of older individuals,if the mean length in the catch is within the interval : Lopt +/- 10%, i.e. 0.9 Lopt < Lmean < 1.1 Lopt.

For Lopt calculation the following equations is used:

logLopt = 1.0421 * logL∞ - 0.2742 (Froese and Binohlan, 2000).

where: L∞ - asymtotic lenght, Lopt – length at max Y/R

Classification of the state of Sprat population according to Lmean

S.sprattus (Lopt=8.0 cm) State of population

good bad mean 8 <7.2

Border values 7.2≤Lmean≤8.8 Lmean<7.2

EQR 0.9

2006 2007 2008 2009 2010 20110

1

2

3

4

5

6

7

8

9

10

11

12

Sample Timing

Le

ng

th C

las

s

Length Frequency Plot

7.20 cm < Lmean < 8.80 cm.

Long-term Lmean

S.sprattus Станция

Lmean,cm мин макс CI (95%) Зона

2007 8.33 5.76 11.55 0.4451

2008 8.45 5.88 11.62 0.5477

2009 7.94 4.99 12.46 0.8122

2010 7.99 4.92 11.72 0.2531

2011 8.33 5 10.6 0.5460

Средно 8.21

Шелфова

Cumulative distribution of Length groups by years

Cumulative contribution of TL=7cm varied 3.2-24.5%(max 2008,min 2010)

Age distribution

Turbot example (Black Sea)

0

500

1000

1500

2000

2500

2006 2007 2008 2009 2010 2011

Години

Мо

ме

нтн

а б

ио

ма

са

(т)

Пролет

Есен

Sc. maeoticus (Lopt=56.0 cм) State of population

good bad mean 56 <56

Border values 50.2≤Lmean≤61.6 Lmean<50.2

EQR 0.9

Lmean Long term

Sc. maeoticus(Lopt=56.0 cм) year

Lmean,cм мин макс CI (95%) zone

2006 44.81 26 76.5 1.691 2007 46.19 26.5 74 0.700 2008 46.28 15 71 0.920 2009 50.92 24 74 0.756 2010 52.44 15 73 2.105 2011 44.34 10 68 3.722

mean (2006 -2011) 47.50

shelf

Cumulative distribution of lenght Калкан

0

25

50

75

100

125

11

.5

17

.5

23

.5

29

.5

35

.5

41

.5

47

.5

53

.5

59

.5

65

.5

71

.5

77

.5

Размерен клас (см)

Ку

мул

ати

вен

%

2006

Калкан

0

25

50

75

100

125

11

.5

17

.5

23

.5

29

.5

35

.5

41

.5

47

.5

53

.5

59

.5

65

.5

71

.5

77

.5

Размерен клас (см)

Ку

мул

ати

вен

%

2007

Калкан

0

25

50

75

100

125

11

.5

17

.5

23

.5

29

.5

35

.5

41

.5

47

.5

53

.5

59

.5

65

.5

71

.5

77

.5

Размерен клас (см)

Ку

мул

ати

вен

%

2008

Калкан

0

25

50

75

100

125

11

.5

17

.5

23

.5

29

.5

35

.5

41

.5

47

.5

53

.5

59

.5

65

.5

71

.5

77

.5

Размерен клас (см)

Ку

мул

ати

вен

%

2009

Калкан

0

25

50

75

100

125

11

.5

17

.5

23

.5

29

.5

35

.5

41

.5

47

.5

53

.5

59

.5

65

.5

71

.5

77

.5

Размерен клас (см)

Ку

мул

ати

вен

%

2010

Калкан

0

25

50

75

100

125

11

.5

17

.5

23

.5

29

.5

35

.5

41

.5

47

.5

53

.5

59

.5

65

.5

71

.5

77

.5

Размерен клас (см)

Ку

мул

ати

вен

%

2011

Thank you for the attention!