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13. ECOLOGICAL IMPACT ASSESSMENT

13.1 Introduction

13.1.1 This section presents the findings of this assessment which includes consideration of the potential and predicted impacts associated with the construction and operation of: a residential development, an access road, sewerage facilities (including pump house and pipeline) and an on-site wetland nature reserve.

13.1.2 The Fung Lok Wai site comprises approximately 80.1 hectares of which about 4.0 hectares (5%) will be affected by the residential development and associated access roads. The remaining 76.1 hectares (excluding the access road) will form the Wetland Nature Reserve (WNR). Figure 13-1 illustrates the site boundary and extent of ecological assessment. For the purposes of this assessment the following areas were defined: • Proposed Development Area – the area directly affected by residential construction; • Wetland Nature Reserve – the area of fishpond enhancement and marshland creation; • Study Site – comprising the Proposed Development Area, the proposed Wetland Nature

Reserve; • 500m Buffer Zone – the buffer established around the Study Site including the access road

for the purposes of the assessment impacts on terrestrial habitats in accordance with the EIA study brief;

• Assessment Area – comprising the study site and the buffer zone. Scope and aims of this Ecological Impact Assessment

13.1.3 In accordance with Section 3.5.6.2 of the Study Brief the spatial extent of this assessment comprises: • all terrestrial and freshwater aquatic habitats present within the boundary of the proposed

development and surrounding 500m buffer zone; and • marine habitats within the entire extent of the Deep Bay Water Quality Inner and Outer sub-

zones (DM3) (EPD, 2000).

13.1.4 The aims of this assessment are to provide sufficient and relevant information to assist the Environmental Protection Department (EPD) and the Agriculture, Fisheries and Conservation Department (AFCD) to: • Identify, assess and evaluate the ecological resources (i.e. Valued Ecological Components

(VECs) and Species of Conservation Importance (SoCI)) that will be affected by construction and operation of the proposed development;

• Identify, assess and evaluate any adverse ecological impacts that will arise during the construction and operation of the proposed development, and evaluate the acceptability of these impacts;

• Identify, assess and evaluate the effectiveness of proposed mitigation measures that will be adopted to minimize or eliminate the predicted ecological impacts that will arise during the construction and operation of the proposed development;

• Identify, assess and evaluate the predicted residual ecological impacts that will arise as a result of the construction and operation of the proposed development following implementation of the proposed mitigation measures;

• Evaluate the acceptability of these residual impacts once the proposed mitigation measures are implemented; and,

• Identify, assess and evaluate the effectiveness of proposed wetland compensation measures, in the form of an on site WNR.

Specific objectives of this assessment 13.1.5 The EIA study brief for this proposal (EPD, 2000) identifies specific objectives and requirements

for the Ecological Impact Assessment. The relevant sub-section within which each of these objectives is addressed is indicated as follows:


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• review and incorporate the findings of relevant studies including the Tin Shui Wai Development Engineering Investigations for Development of Area 3, 30 & 31 of the Development Zone and the Reserve Zone and collate all the available information regarding the ecological characters of the ‘‘Assessment Area’’. Details of the literature review undertaken during the investigation are provided in Section 13.3 and Section 13.4.1 – 13.4.40;

• identify any information gap relating to the assessment of potential ecological impacts to the terrestrial and aquatic environment. Key information gaps are summarised in Section 13.4.41 – 13.4.42;

• carry out any necessary field surveys, the duration of which shall be at least 12 months and cover the winter migratory bird season, and investigations to fill in the information gap, if any, and to fulfil the objectives of the EIA study. Details of the baseline surveys undertaken over 12 months are described in Section 13.5;

• establish the general ecological profile and describe the characteristics of each habitat found within the study boundary, committed ecological measures including those under the EIA Ordinance or the Town Planning Ordinance (such as reinstatement of fishponds) should be taken into consideration; major information to be provided shall include: o description of the physical environment (addressed in Section 13.2); o habitat maps of suitable scale (1:1000 to 1:5000) showing the types and locations of

habitats in the ‘’Assessment Area’’ (provided in Figure 13-9); o ecological characteristics of each habitat type such as size, vegetation type, species

present, dominant species found, species diversity and abundance, community structure, inter-dependence of the habitats and species, and presence of any features of ecological importance (details provided in Section 13.6);

o representative colour photographs of each habitat type and any important ecological features identified (included in Appendix 13-2);

o species found that are rare, endangered and/or listed under local legislation, international conventions for conservation of wildlife/habitats or red data books (addressed in Section 13.6 and summarised in paragraphs 13.6.79 – 13.6.82);

• investigate and describe the existing wildlife uses of various habitats with special attention to: o wetlands including fish ponds, wet agricultural land, marsh; o avifauna; o fung shui woodland; o natural stream courses and man made drainage channels; and o any other habitats and wildlife groups identified as having special conservation interests

by this study (the habitats each species are associated with are described in Section 13.6). • describe all recognized sites of conservation importance in the proposed development site

and its vicinity in particular the Deep Bay Wetland Conservation Area, Wetland Buffer Area, Mai Po Inner Deep Bay Ramsar Site and Tin Shui Wai Wetland Park (now called Hong Kong Wetland Park) and assess whether these sites will be affected by the proposed developments or not (recognised sites of conservation importance are described in Section 13.4 a description of the potential affects of the proposed development on these sites is included in Section 13.8.1 – 13.8.6);

• investigate the impact of the high rise residential buildings in the project area on the bird’s flight path taking into account of diurnal and seasonal patterns (the effects of the construction of high rise buildings on the flightpaths of birds are analysed in detail in paragraphs 13.6.68 – 13.6.76 and under “Habitat Fragmentation” in Section 13.7);

• using a suitable methodology, identify and quantify as far as possible any direct, indirect, onsite, primary, secondary and cumulative ecological impacts such as destruction of habitats, reduction of species abundance/diversity, loss of feeding grounds, reduction of ecological carrying capacity, loss in ecological linkage and function, habitat fragmentation and other possible disturbances caused by the development of the project and the activities of the


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residents (the potential effects of the development are assessed in Section 13.7); • evaluate the significance and acceptability of the ecological impacts identified using well-

defined criteria (the significance of potential impacts are evaluated in Section 13.8); • recommend all possible alternatives (such as modifications of layout and design) and

practicable mitigation measures to avoid, minimize and/or compensate for the adverse ecological impacts identified (mitigation options are described in Section 13.9);

• evaluate the feasibility and effectiveness of the recommended mitigation measures and define the scope, type, location, implementation arrangement, subsequent management, resources requirement and maintenance of such measures (the feasibility and effectiveness of mitigation measures is discussed in Section 13.9);

• determine and quantify as far as possible the residual ecological impacts after implementation of the proposed mitigation measures (residual impacts are described in Section 13.10);

• evaluate the severity and acceptability of the residual ecological impacts using well-defined criteria. If off-site mitigation measures are considered necessary to mitigate the residual impacts, the guidelines and requirements laid down in the TM shall be followed (residual impacts are described in Section 13.10);

• review the need for and recommend any ecological monitoring programme required (see Section 13.11).

• propose a management package for the 71.6 ha Wetland Nature Reserve in the project area with particular attention to (the design and management of the WNR is summarised in Section 13.9 and described in detail in Section 14. Financial and administrative details of the WNR are described in Section 15.): o the habitat management plan and specification of resources requirement for its

implementation; o the long-term trust management system with management guidelines; o the financial arrangement to sustain the management of the wetland; o the management agents and their responsibility; o a contingency plan for the management of the WNR before the well establishment of

trust management;

13.2 Description of the Physical Environment

13.2.1 This sub-section provides details of the geographical and physical context of Fung Lok Wai including past and present land-uses, superficial geology, topography, hydrology and water quality. Location and Regional Context

13.2.2 The study site is located to the south of Inner Deep Bay in the North West New Territories of the Special Administrative Region of Hong Kong. Figure 13-2 illustrates the location of the Assessment Area in the context of the Deep Bay environs. To the west the site is bounded by mangroves along the tidal creeks of the Tai River outfall, beyond which are grasslands, reedbeds, a plantation and fishponds. Further to the west of Fung Lok Wai is Tin Shui Wai New Town. To the north-west there is an area of tidal lagoons (near Tsim Bei Tsui) created by the construction of a causeway for the road and border security fence.

13.2.3 The site is bounded to the north and east by wetland habitats. There is a continuous band of one or two fishponds bound the site to the immediate north, beyond which lies a belt of mangroves which give way to the tidal mudflats and increasingly marine conditions of Inner Deep Bay. Further to the north-east, beyond the Shan Pui River, there is a large area of fishponds and the Mai Po Nature Reserve, a complex of mangrove, gei wai, reedbed and fishponds. Fishponds also bound the site to the east, beyond which is a strip of landscaped land either side of the closed area boundary road, which demarcates the eastern extent of land reclamation. Further east is the Main Drainage Channel for Yuen Long, Kam Tin and Ngau Tam Mei drainage from the Shan Pui River. To the south east lies Yuen Long Sewage Treatment Works to the south of which lies


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Yuen Long Industrial Estate. The south of site is bounded by undeveloped low hills. These are predominantly covered in semi-natural scrub and woodland vegetation with some grassland and orchards. Much of the lower lying areas have been developed for residential housing or cultivated for wet and dry agricultural uses, depending on drainage conditions. Tin Shui Wai new town lies to the south-west and in the western part of the site there are large areas currently under construction relating to the ongoing development of Tin Shui Wai and the operation of Hong Kong Wetland Park. Past and Current Land Use

13.2.4 Originally the Deep Bay area was dominated by brackish and freshwater marshland habitats. However, Deep Bay and its surrounding areas have undergone significant changes over the last century which have been discussed in a number of studies (Melville & Morton, 1983; Young, 1991, Aspinwall Clouston and Wetlands International 1997).

13.2.5 Reclamation of marshes and inter-tidal habitats took place predominantly from the last century until the middle of this century, with 1,200 ha of land being reclaimed between 1903 and 1945. This land was converted to agricultural use, mostly cultivation of brackish water rice and shrimp production in gei wais (tidal shrimp ponds).

13.2.6 Between the mid 1960’s and 80’s brackish and fresh water rice cultivation disappeared and almost all cultivated land and gei wais were converted to deep water fishponds. By 1974, this had become the dominant land use and provided an extensive area of wetland habitat. However, by the same time, virtually all areas of natural and semi-natural freshwater habitat had been lost.

13.2.7 From the late 1970’s to the present urban development has taken over as the main pressure for change in the Deep Bay area, the main impact being the infilling of fishponds and the use of the land for housing, industrial estates and open industrial storage. Between 1985 and 1994, for example, the coverage of fishponds dropped from over 2,000 ha to 1,500 ha, representing a 25% decrease over 10 years.

13.2.8 Furthermore, many fishponds have been abandoned which reduces their ecological value to many important species, in particular herons and egrets. Of the fishponds remaining in the Deep Bay area in 1994 only 78% were still actively managed (Everitt and Cook in press, cited in Aspinwall Clouston and Wetlands International 1997), with the majority located in the North West New Territories, mostly in or within the vicinity of the Mai Po Inner Deep Bay Ramsar Site.

13.2.9 The Fung Lok Wai site has shown similar changes in land use as the Deep Bay area as a whole. In 1924, it is understood that there was a number of large (presumably tidal) lagoons, within the northern half of the site which is now included within the Mai Po Inner Deep Bay Ramsar Site. Some areas of mangrove still appear to be present within the lagoons. The southern area of the site which currently falls outside the Mai Po Inner Deep Bay Ramsar site boundary but within the boundary of the Wetland Conservation Area (WCA) includes some mangrove but also small rectangular fields, which were probably brackish rice paddies.

13.2.10 An aerial photo dated November 1974 shows that most of the site was still tidal at this time; however a number of fishponds had been established in the south-western portion of the site. Since then, virtually the whole site has been converted to freshwater ponds, the majority of which are currently actively used for freshwater fish farming. Geology and Soils

13.2.11 The superficial geology of the site consists of estuarine deposits of marine and fluvial origin, predominantly silts and clays. No borehole information is available from Fung Lok Wai itself, but investigations elsewhere indicate that lenses of sands and gravels of alluvial origin may occur underneath the surface estuarine deposits (see Townland et al. 1992).

13.2.12 The soils of Fung Lok Wai are derived from mangrove soils and ultimately have their origin as marine sediment and riverine alluvium. Texturally the soils are dominated by silt and clay fractions, the relative proportions of which produce soils that vary from clay through silty clay to silty clay loam (USDA texture classes). Sand content is generally low. Very small amounts of gravel are present. The soils have been considerably reworked during reclamation and through management for fish-farming.

13.2.13 Soil samples taken in January 1996 were slightly acidic, with a mean pH of 6.8. The soils are


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poorly drained and frequently highly saline, rendering them of little agricultural value. Topography, Hydrology and Watercourses

13.2.14 The site has an open, flat and low lying aspect. The major variation in site level is due to the excavation of the fishponds and creation of bunds. The level on top of the aquaculture pond bunds vary from approximately +3.1 m to +3.3 m PD, at the north and east of the site, to about +4.2 m PD at the south.

13.2.15 Water for the fishponds comes from direct rainfall. During winter and when ponds are drawn down, water is pumped from one pond to another to conserve resources. After heavy summer rainfall, ponds may fill and drain into adjacent channels. Channels may also occasionally be used for transferring water, by pump, between fishponds.

13.2.16 No flow data are currently available for the drainage channels. However, a site inspection on 10th January 1998 revealed that all channels contained shallow water (c. 10 cm) and that there were low flows from those draining catchments the adjacent catchments to the south.

13.2.17 The mangrove lined channel (Tai River outfall) at the north-western perimeter of the site is intertidal. The perimeter bunds are approximately +3.8 mPD and higher than the predicted mean high water in the channel (+2.4 m PD). Therefore in normal circumstances the interior of the site remains free of tidal influence. Overtopping of the perimeter might occur in an extreme combined high tide and storm event. However, this is likely to be extremely rare given the past extreme sea levels at nearby Tsim Bei Tsui which peaked at +3.85 mPD with a return period of 100 years for records between 1974 and 1990. The predicted tidal range for 2002 at Tsim Bei Tsui is 0-3 mPD with an average peak tide of +2.4 mPD. Water Quality

13.2.18 The results of water quality sampling in the fishponds at Fung Lok Wai undertaken in May 2002 (ALS Technichem (HK) Pty Ltd) are shown in Table 13-1 below. These data suggest that water quality in the ponds is in accordance with the following AFCD (1995) recommendations for fishponds: pH 6 - 8.5; dissolved oxygen > 1 mg/l; salinity < 2 mg/l.

13.2.19 Dissolved oxygen concentrations, often regarded as the most important measure of water quality, are high in all of the ponds measured, with the exception of Ponds 56 and 62 (see Figure 13-1 for locations). High oxygen saturation levels are perhaps not surprising given the widespread use of pond aerators by the fish farmers.

13.2.20 No data are currently available on the quality of water in the existing watercourses. However, all the catchments are dominated by dense semi-natural scrub and woodland vegetation and there are no apparent point sources of pollutants such as pig farms etc. It is therefore expected that the water entering the site is likely to be of relatively low nutrient status and with a low Biological Oxygen Demand (BOD). It is also anticipated that suspended silt in runoff during heavy rainfall periods is likely to be relatively low due to the existing dense vegetation cover in the catchments. Further analysis of water quality survey results can be found within the Water Quality Impact Assessment chapter of this EIA report.

Table 13-1 Results of Water Quality Monitoring in Fishponds at Fung Lok Wai (May 2002)

Sampled Fish Pond River water Sampling Stations

Parameters Pond 2 Pond 13 Pond 19 Pond 56 Pond 59

Pond 62

W1 (Shan Pui River)

W2 (Tai River)

pH 6.2 7.7 9.3 6.9 8.9 7.0 7.8 7.5

Conductivity (uS/cm) 2510 1860 635 1640 1100 1100 16500 21500

D.O. (mg/L) 5.4 4.4 7.2 2.6 8.2 2.4 3.1 2.1

% Saturation of D.O. (%)

72.5 62.2 98.1 38.5 108 28.1 41.7 28.7

Temp. (oC) 31.3 31.0 30.4 30.7 32.5 30.5 30.0 29.0


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Sampled Fish Pond River water Sampling Stations

Parameters Pond 2 Pond 13 Pond 19 Pond 56 Pond 59

Pond 62

W1 (Shan Pui River)

W2 (Tai River)

Salinity (mg/L) 1.1 0.5 0.3 0.7 0.5 0.5 8.8 11.9

Turbidity (NTU) 45.2 30.7 23.1 63.3 23.5 42.4 12.7 20.0

SS (mg/L) 72.7 57.0 28.3 93.7 47.0 49.7 32.3 26.3

Ammonia as N (mg/L) 0.03 0.03 0.04 2.96 0.07 0.39 5.4 2.8

Nitrate as N (mg/L) <0.01 <0.01 <0.01 0.04 0.04 0.23 0.6 0.7

Nitrite + Nitrate as N (mg/L)

0.02 0.02 0.02 0.16 0.17 0.31 0.9 1.2

Total Kjeldahl Nitrogen as N (mg/L)

3.2 2.9 3.9 4.6 3.3 3.6 7.3 3.1

Total Nitrogen (mg/L) 3.2 2.9 3.9 4.8 3.5 3.9 8.2 4.3

Total Phosphorus (mg/L)

0.2 0.2 0.2 0.2 0.2 0.3 0.7 0.5

Reactive Phosphorus as P (mg/L)

0.03 0.03 0.02 0.02 0.03 0.02 0.6 0.4

BOD (mg/L) 10.0 8.7 14.3 5.3 9.0 4.7 3.0 <2

13.3 Literature Review

13.3.1 In order to identify key ecological resources and issues, relevant reports and scientific papers have been reviewed below. A key objective of this review is to identify important information gaps and appropriate strategies for additional data gathering. In particular, the results of species and habitats surveys undertaken at Fung Lok Wai between 1994 and 1998 are drawn upon, (Mutual Luck Investment Limited 1998).

13.3.2 A full list of documents referenced during the preparation of this EcIA is included in Section 13.12. However, the following documents are particularly relevant to this assessment: • Bats of Hong Kong. World Wide Fund for Nature, Hong Kong. Ades, (1990). • Classification system for wetland type, Ramsar Bureau. www.ramsar.org • Development of a comprehensive conservation strategy and a management plan in relation to

the listing of Mai Po and Inner Deep Bay as a Wetland of International Importance under the Ramsar Convention. Agreement No. CE47/95. Aspinwall Clouston & Wetlands International – Asia Pacific (1997).

• Ecological impact study of proposed development at Pak Hok Chau, Mai Po. Unpublished report. Anon. (1993).

• Ecological study on mangrove stands in Hong Kong. Report submitted to AFD, Hong Kong SAR. Tam, N.F.Y. & Wong Y. (1997).

• Environmental Impact Assessment: Towards Guidelines of Adoption under the Ramsar Convention. Technical Session A of the 6th meeting of the conference if the contracting parties, Brisbane, March 1996. Pritchard, D. E. (1996)

• Fish Ponds in the Ecology of the Inner Deep Bay Wetlands of Hong Kong. Asian Journal of Environmental Management. Vol 3, No. 1, pp13-36. Chu, W. H. (1995)

• Guidelines for application for developments within Deep Bay Area under section 16 of the Town Planning Ordinance. TPB PG-No. 12B. Town Planning Board (1999)

• Hong Kong International Wetland Park and Visitor Centre Feasibility Study – Preliminary Environmental Review. Hong Kong Tourist Association. Binnie Black and Veatch (1999).

• Objection to Draft Lau Fau Shan & Tsim Bei Tsui Outline Zoning Plan No. S/YL-LFS/1 –


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Alternative Proposal. Volume 1 and 2. Mutual Luck Investment Limited (1998). • Pilot project to develop a long-term strategy for the conservation of fish pond farming within

the Mai Po and Inner Deep Bay Ramsar Site. Funded by the Conservation Foundation Fund, Hong Kong. World Wide Fund for Nature (2003)

• Ramsar Site Waterfowl Monitoring Programme, Hong Kong Bird Watching Society. Carey, G. (unpublished).

• Reconnaissance survey of benthic and pelagic fish pond fauna at Fung Lok Wai. Prepared for Mutual Luck Investment Limited. Binnie Consultants Limited (1997a).

• Sheung Shui to Lok Ma Chau Spur Line Environmental Impact Assessment. Binnie Black and Veatch 2000.

• Study on the Ecological Value of fish Ponds in Deep Bay Area: Executive Summary. Planning Department, Hong Kong SAR Government. Aspinwall & Company Hong Kong Limited (1997).

• Sunnyville Estate development at Nam Sang Wai, Engineering Assessment Report, Nam Sang Wai Development Co, Ltd & Kleener Investment Ltd. Townland Consultants Ltd, Wong Tung & Partners Ltd, Maunsell Consultants Asia Ltd, MVA Asia Ltd, CES Asia Ltd, Belt Collins & Associates HK ltd, Nelson and Wright (1992).

• The Avifauna of Hong Kong. Hong Kong Bird Watching Society, Hong Kong. Carey, G.J. et al. (2001).

• The importance to ardeids of the Deep Bay fishponds, Hong Kong. Biological Conservation. 84 (3): 293-300. Young, L.(1998).

• The significance of drained fishponds for wintering waterbirds at the Mai Po Marshes, Hong Kong. IBIS, 139 (4): 694-698. Young, L. (1997).

• Tin Shui Wai Development Engineering Investigations for Development of Area 3, 30 & 31 of the Development Zone and the Reserve Zone – Environmental Impact Assessment - Final Assessment Report. Volumes 1 and 2, February 1997. Territory Development Department, Agreement No. CE 10/95. Binnie Consultants Limited (1997b).

• Various issues of Porcupine! Newsletter of the Department of Ecology and Biodiversity, Hong Kong University.

• Wild Animals to Watch: Terrestrial and freshwater fauna of conservation concern in Hong Kong. Memoirs of the Hong Kong Natural History Society. Fellowes, J.R et al. (in 2002).

• In formation about the wildlife of Mai Po Marshes available at http://www.wwf.org.hk/eng/maipo/wildlife/habitats.html

• Yuen Long Bypass Floodway Feasibility Study Environmental Impact Assessment Binnie Consultants Limited (1998).

• Yuen Long and Kam Tin Sewerage and Sewage Disposal Stage 1 Sewers, Rising Mains and Ancillary Pumping Stations: Environmental Impact Assessment and Traffic Impact Assessment Studies. Environmental Impact Assessment (Designated Elements) Final Report. ERM (May 2002).

13.4 Review of Recognised Sites of Conservation Importance in the Vicinity of Fung Lok Wai

13.4.1 The location of the proposed development in relation to existing protected areas of high ecological value is indicated in Figure 13-2. The northern boundary of the Assessment Area adjoins the Inner Deep Bay Site of Special Scientific Interest (SSSI) and the northern half of the Assessment Area lies within the boundary of the Mai Po Inner Deep Bay Ramsar Site (a Wetland of International Importance under the Ramsar Convention). The Deep Bay area comprises natural and man-made wetlands (rivers, freshwater marshes, fishponds, gei wais (tidal shrimp ponds), mangroves, inter-tidal mudflats and the bay) which provide a wide range of habitats that support a high diversity of biota (plants, insects, reptiles, amphibians, birds, fish and mammals). To the north east is Tsim Bei Tsui Egretry SSSI and to the west beyond the Shan Pui River is Mai Po Nature Reserve and Mai Po Marshes SSSI.


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13.4.2 The Mai Po Inner Deep Bay Ramsar site is particularly important for waterbirds, including a number of globally threatened species (Collar et al. 1994), species which regularly have high proportions of their global or biogeographical wintering or passage populations within the site and species that are of regional or local conservation importance. Deep Bay is also important for a wide range of other migratory water birds, many of which are listed for protection under the Convention on the Conservation of Migratory Species of Wild Animals (Bonn Convention) of which the People’s Republic of China is a party.

13.4.3 The Town Planning Board has adopted a “precautionary approach” to development in the Deep Bay area in view of the known intrinsic value of fishponds in ecological terms, and the complex response of birds to future land use changes which has not been fully understood (Town Planning Board 1999). The intention is to protect and conserve the existing ecological function of fishponds in order to maintain the ecological integrity of the Deep Bay wetland ecosystem as a whole. This “precautionary approach” is formulated with the support of scientific surveys and analysis as provided in the Study on the Ecological Value of Fish Ponds in the Deep Bay Area (Aspinwall Clouston & Wetlands International - Asia Pacific, 1997).

13.4.4 The Wetland Conservation Area (WCA) forms the core wetland area of Inner Deep Bay between Tin Shui Wai in the west and the Lok Ma Chau Boundary Crossing in the east and has been designated for all continuous and adjoining fishponds within this area, including those within the study site. The intention of the WCA designation is to conserve the ecological value of fishponds which form and integral part of the wetland ecosystem in the Deep Bay Area. A Wetland Buffer Area (WBA) of 500m to the landward side of the WCA has also been designated to protect the ecological integrity of the WCA.

13.4.5 In considering development proposals in the Deep Bay Area, the Town Planning Board adopts the Fish Pond Study’s recommended principle of “no-net-loss in wetland” which provides for the conservation of continuous and adjoining fishponds. The no-net-loss can refer to both loss in “area” and in “function”. Wetland compensation is required for any development requiring pond filling and mitigation measures against disturbance are also required.

13.4.6 Management zonation has been developed for the Mai Po Inner Deep Bay Ramsar Site as part of its Comprehensive Conservation Strategy and Management Plan (Aspinwall Clouston and Wetlands International 1997). The areas within the Ramsar boundary to the west, north and east of the site have been identified as Public Access Zones. According to the Strategy, “the purpose of the Public Access Zones is to enable people to have unrestricted (but managed) access to a part of the Ramsar site in order to appreciate its special value and enjoy contact with wildlife. In addition it provides opportunities for: public education, raising public awareness of the conservation values of the site, particularly as they relate to the Ramsar criteria values and biodiversity values; and quiet recreation relevant to the aforementioned values”. The area of the Fung Lok Wai site within the Ramsar boundary was not included in the Public Access Zone as the Strategy did not propose management zones for privately owned land. Habitats

13.4.7 As described in Section 13.2 Deep Bay was originally dominated by a complex of natural wetland habitats, including inter-tidal mudflats, mangroves and brackish and freshwater marshland. This century large areas of these inter-tidal habitats have been reclaimed and other wetlands drained, infilled or converted to artificial gai wais or fish pond habitats. Consequently, only small areas of natural and semi-natural wetlands remain in the Deep Bay area, mainly around Ma Tso Lung.

13.4.8 These changes in habitats will have had profound impacts on the distribution and abundance of many species that were originally associated with these natural wetland habitats. Although data are not available to assess the longer-term impacts, it is generally accepted that many wetland species that are currently rare or no longer occur in Hong Kong formerly commonly occurred in the Deep Bay area.

13.4.9 The remaining areas of wetland habitats are of local and regional importance in their own right. The mangrove forests at Mai Po together with those in the other parts of Deep Bay cover an area of some 400 ha and are the sixth largest protected stand remaining in China. Mangroves provide important habitats for wildlife but in Hong Kong most other stands are relatively small and


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subject to frequent human disturbance (Tam & Wong 1997). Reedbeds at Mai Po represent greater than 80% of all reedbed habitat in Hong Kong are one of the largest remaining areas known in Guangdong Province and 240 ha of traditionally operated shrimp ponds represent one of the largest areas of this habitat left in southern China (WWF 2000).

13.4.10 Despite the loss of areas of natural and semi-natural wetlands to artificial habitats some of the more recent changes are likely to have had beneficial effects for some species. In particular, it is likely that the high productivity of the fish farming systems and the availability of abundant food during fish harvesting periods has maintained or increased populations of many water birds, including cormorants, herons and egrets. The value of fishponds to some specific groups, in particular to birds, has been well studied (see below), although a comprehensive assessment of the importance of different habitat types in the area of Inner Deep Bay, to different species groups, has yet to be undertaken.

13.4.11 Chu (1995) undertook a review of the ecological surveys carried out for five planning applications within the Deep Bay area to assess the relative importance of fishponds and associated habitats for wildlife. The review demonstrates that fish pond areas can support a number of protected species and are an important habitat for resident ardeids and migrant birds. In addition, summaries of species known to be associated with fishponds have been produced (Ades et al. 1995). These summaries indicate that fishponds within the Deep Bay area, although artificial, are an integral part of the Deep Bay wetland ecosystem. Vegetation

13.4.12 Approximately 120 terrestrial plant species have been recorded from the Deep Bay aquaculture pond bunds (Chau, unpublished data). However, most of these are common and widespread species (Ades et al. 1995).

13.4.13 Surveys of the vegetation around the fishponds at Fung Lok Wai were undertaken on 9th November 1994, 28th February 1995 and 16th May 1996. Additional species recorded during the course of other visits to the site were also added to the plant species list. All plant species encountered whilst walking the bunds were recorded, with an estimate made of their abundance within the site.

13.4.14 Areas of mangrove vegetation occurred immediately outside the site but none were found within its bounds. A small population of the mangrove fern Acrostichum aureum was, however, found in a drainage ditch in the western part of the site.

13.4.15 The bund vegetation at Fung Lok Wai during this survey consisted predominantly of coarse grassland, composed of common grasses and herbs. The vegetation is subject to frequent disturbance in the form of cutting, burning, rubbish dumping and, when the ponds are reformed, bulldozing. As a result of this disturbance ruderal or 'weed' species are a prominent feature, some such as the alien climber Mikania micrantha having spread to form extensive patches.

13.4.16 The most interesting vegetation community recorded within Fung Lok Wai during these surveys was that associated with the drainage ditches. Apart from supporting predominantly alien trees and shrubs on their banks, the drainage ditches also supported elements of wetland vegetation. This ranged from areas of dense reed Phragmites communis and low scrub of Marsh Fleabane Pluchea indica to open marsh vegetation of Cyperus sedge and other marginal/emergent species. The relatively undisturbed nature and dense vegetation found in many of these ditches provide cover for wildlife.

13.4.17 A total of 76 plants species were recorded during these surveys. No unusual or rare plant species were encountered. Invertebrates

13.4.18 A survey of invertebrates present in seven fishponds exhibiting a range of conditions was carried out on 4th and 9th November and 21st December 1994. Invertebrate species richness was found to be very low in all of the surveyed ponds. The fauna of mature and recently drained ponds was typically dominated by freshwater shrimps, almost exclusively belonging to the genus Palaemon. Pelagic insects were very scarce, with only a few backswimmers (Notonecta sp.) being encountered in one of the ponds.

13.4.19 Shrimp were not detected in recently re-filled ponds. Some of these ponds did, however, support


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large numbers of non-biting midges (Chironomidae). Adult Chironomids were seen emerging in abundance from a recently re-profiled and filled pond. Exuviae collected from this pond were identified by Dr M. Learner, University College, Cardiff, as belonging to three genera - Einfeldia, Chironomus and Nilodorum (Einfeldia being the most abundant).

13.4.20 Sieve sampling of bottom muds in a re-profiled and re-filled pond, revealed the presence of large numbers of benthic Chironomid larvae. These were present in sediments c. 1 metre below the water surface. These were identified as Einfeldia and Chironomus, with the former again the most abundant. Densities of benthic larvae were estimated at approximately 1,800 m-2. Gelatinous egg masses, also belonging to chironomids, were found around the margins of recently re-filled ponds, attached to clumps of clay just below the water surface.

13.4.21 A further study of three ponds at Fung Lok Wai in March 1997 also confirmed that Chironomid larvae are the predominant benthic species present, followed by tubificid worms (Binnie Consultants Limited 1997b). In total only 14 benthic taxa were recorded.

13.4.22 Searches of micro-habitats around the margins of ponds revealed a number of crabs (Varuna litterata).

13.4.23 30% of all dragonfly species recorded in Hong Kong can commonly be encountered around managed fishponds. Most of these are generalists which prefer static conditions and, in comparison to natural ponds and lakes, managed fishponds support a reduced number of dragonfly species (Wilson 1995a & b). Two species of dragonfly and damselfly of conservation interest have been recorded with the Deep Bay area though not within the Assessment Area of Fung Lok Wai, Orthetrum poecilops poecilops and Mortonagrion hirosei. Orthetrum poecilops poecilops is normally associated with woodland. Mortonagrion hirosei is usually confined to dense Phragmites reed beds, so both are unlikely to occur within the Study Site.

13.4.24 Invertebrate surveys of bund habitats were undertaken within three sampling areas of aquaculture ponds within the Deep Bay area as part of the Fishpond Study (Aspinwall Clouston & Wetlands International – Asia Pacific 1997). The results of the survey indicate that the ponds support an impoverished and very simple aquatic invertebrate community. Freshwater shrimps are the predominant group. Present in large numbers, they are an important food source for herons and egrets.

13.4.25 Aquatic insects are generally quite scarce, except for Chironomid midges that were found in some abundance in recently re-filled ponds. These insects are also important food sources for birds, including Chinese Pond Herons and migratory passerines such as Acrocephalus warblers. The results indicated that 46% of all invertebrates recorded were Chironomid midges, with Hemiptera, Arachnida and other Diptera making up a further 42% of all records. Total biomass peaked in spring. The greatest species group diversity occurred within the scrub areas, though only by small margin; grassland areas supported the greatest biomass and reedbeds the greatest density. All site surveys were dominated by Diptera.

13.4.26 These findings are in broad agreement with studies at Pak Hok Chau (fishponds near Mai Po Nature Reserve), which found a low diversity of species overall, but with large numbers of a few species (principally flying insects such as Chironomids) at certain periods, notably during spring and autumn (Anon. 1993). Fish

13.4.27 The fishponds are actively used for the polyculture of freshwater fish, and therefore contain high densities of various commercially stocked species (including Big Head Carp Aristichths nobilis, Grass Carp Ctenopharyngodon idellus, Common Carp Cyprinus carpio, Grey Mullet Mugil cephalus and Tilapia spp.). In addition high numbers of various non-commercial species are likely to occur, including Mosquito Fish Gambusia patruelis. Amphibians

13.4.28 Eight species of amphibians, a third of the native Hong Kong amphibian fauna, have been recorded from fishponds in the Deep Bay area (Lau 1995). However, predation of tadpoles by fish and the slightly saline water make the fishponds at Fung Lok Wai unsuitable habitats for most amphibians and only Guenther's frog Rana guentheri are known to breed in the ponds.

13.4.29 Five species of amphibian were found off site at the nearby Tin Shui Wai Reserve Zone (Binnie


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Consultants Ltd 1997a). However, only Guenther’s frog and Asiatic toad Bufo asiatica, both common and widespread species, were recorded at Fung Lok Wai at this time. Reptiles

13.4.30 In total 16 species of reptiles have been recorded from the fishponds in the Deep Bay area including five species of reptile of conservation importance which are known to occur within the north-west New Territories, Chinese Soft-shelled Turtle Pelodiscus sinensis, Chinese Three-keeled Pond Turtle Chinemys reevesii, Burmese Python Python molurus, Chinese Cobra (Naja atra) and Copperhead Racer Elaphe radiata. Of these Chinese Soft-shelled Turtle, Chinese Three-keeled Pond Turtle and Burmese Python are protected under Schedule 2 of the Hong Kong SAR Wild Animals Protection Ordinance. These three species are also recorded on the IUCN list of globally threatened species. Chinese Soft-shelled Turtle and Chinese Three-keeled Pond Turtle prefer reservoir and pond habitats with soft sediments and so could occur within the habitats of Fung Lok Wai, however the distribution of Chinese Soft-shelled turtle is localised. Burmese Python is unlikely to utilise the fishpond habitats of the Study Area preferring instead scrubby and mangrove habitats.

13.4.31 Although a comprehensive reptile survey was not carried out at Fung Lok Wai as part of the original proposal, the following species were recorded: Chinese water snake Enhydris chinensis (juvenile found under sacking on edge of pond 7) and common rat snake Ptyas mucosus (discarded skin found on bund between pond 21 & 22). In addition, checkered keelback snake Xenochrophis piscator, Bowring's gecko Hemidactylus bowringii, many-banded krait Bungarus multicinctus, common rat snake Ptyas mucosus and three keeled pond turtle have been recorded nearby, and are therefore likely to occur on site. In general the regular disturbance to aquaculture ponds associated with the intensive fish farming at Fung Lok Wai is likely to limit opportunities for reptile populations to become well established. Birds

13.4.32 Of all species groups, birds have been the subject of most studies and surveys of the fishponds of the Deep Bay area. These include feeding studies by Melville (1987), Wong (1991), Britton (1993) and Young (1993). Further ecological appraisals have been made on the use of fishponds by birds by Melville et al. (1994) and Chu (1995). A detailed assessment of the use of fishponds by birds was completed as part of a Fish Pond Study by the Planning Department in 1997 whose specific aim was to assess the ecological value of fishponds within the Deep Bay area.

13.4.33 Fish ponds are used by a wide range of waterbirds, land birds associated with bund vegetation and birds feeding aerially on insects above the water. These include a wide range of raptors, waders, gulls, terns and passerines. Ponds are used by different species at different times of the year, a large proportion of which occur in high numbers in the Deep Bay area. In fact the similarity in the bird community composition at Mai Po Nature Reserve and the fishponds suggests that they should be treated as an integrated unit because birds regularly move between the two. Overall, it is understood that the fishponds provide habitat for half the number of waterbirds found at Mai Po and 10% of the number of the entire Deep Bay area, though proportionately more egrets, herons and cormorants, use fishponds than the other habitats within Deep Bay (Aspinwall Clouston and Wetlands International 1997).

13.4.34 Wintering bird data collected by the Hong Kong Bird Watching Society (HKBWS) since 1979 indicate there has been a significant increase in total waterfowl using the Deep Bay Area in Hong Kong (Carey et al. 2001) and in total numbers of herons and egrets, ducks, waders and cormorants (Aspinwall Clouston and Wetlands International 1997). However, numbers at Mai Po and Futian (on the northern shore of Deep Bay, in mainland China) have remained relatively constant, suggesting that the current carrying capacity of these sites has been reached.

13.4.35 The increase in herons and egret populations in winter is due to birds using both Deep Bay itself and the wider fish pond habitats throughout the bird count areas. This increase in use is most likely due to a decrease in persecution of breeding individuals, an increase in food supplies in the breeding and wintering period, and the loss of habitats outside Deep Bay.

13.4.36 Winter population increases in ducks is most likely the result of increased prey biomass in the Deep Bay mudflats, due to organic enrichment, increases in total flyway populations and habitat loss elsewhere in the region. Similarly wader populations have probably benefited from the


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organic enrichment of the mudflats, as well as an increased provision of high tide roosts within Deep Bay and associated habitats at Mai Po. Increased observer coverage may also account to some extent for the increase in numbers counted.

13.4.37 Comprehensive surveys of the birds occurring at the Fung Lok Wai site were undertaken between 2nd December 1993 and 27th November 1997. A total of 100 species of birds were recorded at Fung Lok Wai over the course of the surveys. Although many of the birds recorded do not visit the site regularly; at least 33 regularly occur, including ubiquitous species like tree sparrow and Chinese Bulbul and those, like Chinese Pond Heron, Little Egret and Common Kingfisher, which regularly feed around ponds. Of the regular species, 19 (58%) could be reasonably described as wetland birds including some of conservation importance, such as Little Egret, Cattle Egret and Chinese Pond Heron. However, the number and diversity of several waterbird groups such as Snipe, rails, crakes and reedbed passerines appeared to be low, probably as a result of the intensive management of fishponds and consequent lack of emergent vegetation.

13.4.38 A specific review of the effects developments may have on egretry sites has been completed as a separate report (AEC 2002). Evaluation of the current bird interest at the site is described in section 13.5 below. Mammals

13.4.39 Eleven mammal species have been recorded from aquaculture ponds (fishponds that are actively managed, those that are currently unmanaged, and the intervening bunds) and vegetation at the nearby Mai Po marshes (Ades et al. 1995). In particular the Chinese Otter which was considered extinct in Hong Kong until its rediscovery in 1990 at Mai Po. A detailed survey of mammals occurring at Fung Lok Wai was not undertaken during documented previous surveys and the only mammals noted during site visits were brown rat Rattus norvegicus and Japanese pipistrelle bat Pipistrellus abramus. In addition, house shrew Suncus murinus and house mouse Mus musculus would also be expected to occur. Crab eating mongoose Herpestes urva has also been seen off site, in nearby mangrove and Melville (1991) has predicted that small Indian civet Vivericula indica and leopard cat Felis bengalensis could occur at nearby Nam Sang Wai.

13.4.40 Documents associated with EIAs prepared for previous development proposals in the Deep Bay Area were reviewed but provided little additional information on mammalian fauna of the area. In general though, the disturbance from the intensive fish pond management and lack of vegetation cover at Fung Lok Wai is likely to make the site unsuitable for most larger mammals. Summary of Key Information Gaps

13.4.41 No habitat or species survey data reviewed were found to be up to date, comprehensive or covering the complete Assessment Area as required by the Study Brief. A comprehensive suite of surveys were therefore proposed for all habitats, aquatic invertebrates, terrestrial invertebrates known to have some association with the habitats occurring at the site, wild freshwater fish, amphibians, reptiles, birds and mammals.

13.4.42 The information gained from the review of existing information above will be utilised along with the data obtained from recent surveys to identify, predict and evaluate impacts and formulate appropriate mitigation measures and monitoring for the site.

13.5 Field Survey Methodology

13.5.1 The field survey methodology utilised for this EcIA follows the general principles outlined in Annex 16 of the Technical Memorandum to the EIA Ordinance and aims to provide adequate and accurate baseline survey information of the proposed development and its vicinity, with respect to the ecological importance of flora, fauna and habitats found. Section 6.8 of the Town Planning Board planning guidelines TPB PG-No. 12B (Town Planning Board 1999) stipulates that for development proposed within or encroaching either the WBA or WCA, baseline surveys should be undertaken over twelve consecutive months to establish the existing wildlife habitats and flora and fauna present and any seasonal changes.

13.5.2 The baseline habitat and ecological surveys for the study site commenced on the 10/1/2001 and were completed on 3/1/2002. The surveys were conducted by qualified, professional ecologists with at least three years relevant expertise in surveying their respective taxa groups in Hong


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Kong and South China.

13.5.3 Since completion of the surveys there has been no change in wetland area, there has been no in-filling of fish ponds, for example. There has, however, been a change in management of fish ponds. Site visits undertaken in recent years, including by WWF staff in October 2006 and May 2008, indicate that relatively few ponds (about one quarter) are now in active production (Janet Lee, Pers. Comm.). For abandoned ponds, grass has encroached into the open water from the side of the ponds and Water Hyacinth (Eichhornia crassipes) is abundant in some cases. In the absence of active management, bunds have become covered by long grass which reduces their attractiveness as roosting sites for waterbirds.

13.5.4 As the extent of wetland has not changed it is considered that the importance of the site for most species, including birds that are not dependent on the active fishpond management (eg Red-billed Starling) and non-avian fauna (such as reptiles) will be unchanged. For those birds that are dependent on the active management of fish ponds (including egrets and Black-faced Spoonbill) it is expected that the importance of the site will have declined.

13.5.5 To determine whether there have been changes within the wider north-west New Territories in the abundance of key bird Species of Conservation Importance, an analysis of bird records within the Deep Bay area has been undertaken (Appendix 13-12). This analysis includes a comparison of recent records within a recording area that includes Fung Lok Wai with data for the wider Deep Bay area. It indicates that there is no significant change in the importance of Fung Lok Wai for Species of Conservation Importance since the conclusion of the baseline surveys and that, for key species (egrets and Black-faced Spoonbill) there appears to be a loss of value.

13.5.6 It is considered that the results of these surveys remain applicable to the assessment. Any changes taking in place in the intervening period involving a reduction in ecological value due to a reduction in fish farming activity. There is evidence that this had most effect on key bird species of interest such as egrets and Black-faced Spoonbill that typically benefit most from aquaculture activities that periodically provide access to food resources. Habitats

13.5.7 Aerial photograph of the study site supplied by the Lands Department (CN27931, 10/8/2000) was used to delineate the boundaries of the different natural and artificial habitats present within the Assessment Area. The boundaries of each habitat type were transcribed onto a 1:5000 scaled map and ground-truthed on subsequent site visits. Representative colour photographs were taken of each habitat. Wetland habitat types were classified according to the ‘Ramsar Classification System for Wetlands’ (Appendix 13.1) and terrestrial habitats were classified on the basis of the structural characteristics of the dominant vegetation present. The completed habitat map was digitised into MapInfo V.6.

13.5.8 The total area in hectares (ha) and percentage coverage of each habitat type present within the Assessment Area was calculated using a Lands Department digital topographic base map of the site which was ground-truthed and geocoded. Vegetation

13.5.9 Following production of the habitat map habitat surveys were undertaken by a suitably qualified botanist.

13.5.10 Each habitat within the Assessment Area was inspected and a species list and a semi-quantitative estimate of abundance recorded.

13.5.11 More detailed quantitative surveys to determine species composition were undertaken within those habitats present within the Study Site during both wet and dry seasons. Within each of these habitats, ten randomly distributed 1m2 fixed quadrats were surveyed. Quadrat locations were permanently marked to enable resurvey and hence direct comparison between seasons. The data were recorded as percentage cover of each species identified within three growth layers. In addition, notes were made of: • Vegetation structure • Dominant plant species • Condition


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• Presence of any specific features of ecological significance

13.5.12 Quadrat locations are identified in Figure 13-3. Invertebrates Aquatic Invertebrates

13.5.13 The aquatic invertebrate community was sampled at a total of nine locations across the site using a combination of three survey techniques to enable all major aquatic biomes to be sampled. Aquatic sampling locations are shown in Figure 13-4.

13.5.14 Permanent watercourses were surveyed using pond net and kick sampling during the wet season in August 2001 and repeated again during the dry season in December 2001, using the same sampling locations in both seasons to gain a representative sample of the aquatic invertebrate community during both periods.

13.5.15 Fishponds were surveyed using pond net and benthic core sampling again during both the wet and dry seasons.

13.5.16 Pond net – Sweep net sampling was conducted within the study site to assess the species composition and abundance of aquatic species that inhabit the water column and cling to submerged vegetation present in the permanent streams. A D-shaped sampling net 30 cm in diameter comprising 1 mm mesh was used. Each sample comprised two 2-metre sweeps of the net. The first sweep was conducted through the mid water column, whilst the second sweep was passed over the bed of the watercourse. For each sample site the replicate samples were combined, preserved and stored.

13.5.17 Three permanent watercourses present within the study site were surveyed. Three random samples were being taken at each sampling location.

13.5.18 Six fishponds were sampled across the study site with five random samples being taken within each pond along the water/bund interface. A larger sample size was used during the survey of aquatic invertebrates in the fishponds, as these represent a significantly larger area of the study site.

13.5.19 Kick net – Kick net sampling was used to sample the macro-invertebrates that inhabit the soft substrate of the streambed. A kick net of the following dimensions: height = 0.25m, width = 0.3m, length = 0.5m and a mesh size of 1mm was used. The flat base of the kick net was placed on the stream bed and held securely. The open mouth of the net was placed facing upstream. A surveyor kicked a 1m2 area of substrate on the stream bed, directly upstream of the net, ten times to dislodge macro-invertebrates inhabiting the sediment. Any invertebrates caught in the net were removed and preserved in 70% alcohol for later identification.

13.5.20 In the laboratory each sample was rinsed onto a 500 micron fine mesh sieve to remove sediment particles. The washed samples were sorted into species groups. Specimens of target taxonomic groups were identified to family level using a binocular microscope, and the number and biomass (dry weight, including shell in the case of molluscs) of each family represented was quantified. The target species groups include: Coleoptera: beetles, Crustaceans: crabs, shrimps, Diptera: chironomids, psychodids, Ephemeroptera: mayflies, Heteroptera: water bugs, Hirundinea: leeches, Mollusca: shellfish, Tipulids: craneflies, Trichoptera: caddisflies. Species for other taxa groups were recorded and counted, but not weighed. The number and species of any fish incidentally captured during the sampling was also recorded.

13.5.21 Two permanent watercourses were sampled using kick netting. This method is inappropriate for sampling closed waterbodies with no flow current, so a different method, benthic core sampling, was used to survey the benthic invertebrate community within the fishponds.

13.5.22 Cylindrical benthic cores – Benthic cores were taken from six fishponds within the study site to identify the species composition and abundance of freshwater invertebrates that inhabit the soft substrate along the shallow aquatic margins of the ponds. This sampling method was used to assess the value of the current fishpond margins to waterbirds. The fishponds were sampled once during the wet season in August 2001 and resurveyed during the dry season in December 2001.

13.5.23 Cylindrical benthic cores 10cm in diameter and 20cm in length were inserted into the submerged sediment to a depth of 10cm, rotated and gently removed. Six randomly located replicate cores


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were collected from each pond.

13.5.24 The contents of each core were immediately removed and preserved in 70% ethanol. Back in the laboratory each core was washed on a 500 micron fine mesh sieve to remove all sediment particles. Invertebrates were identified to family level under a binocular microscope. The number and biomass (dry weight, including shells in the case of gastropods) of individuals in each target taxonomic group was quantified, as for the kick-net sampling. Species from other taxa groups were recorded and counted, but not weighed. Dragonflies

13.5.25 Dragonflies were surveyed by a suitable qualified ecologist along the set transect routes T1-T10 (Figure 13-5). Dragonflies were surveyed twice per month during May, June, September and October 2001, and once per month in April, July, August and November 2001.

13.5.26 Each survey commenced at the beginning of transect T1. The surveyor walked along the entire length of each of the transects T1 to T10 in sequential order at a uniform pace. All butterflies and dragonflies identified in front of and within 5 metres either the side of each transverse (but not behind) the surveyor were recorded. Where feasible the number of male and female dragonflies observed were recorded for each species. Where large swarms of dragonflies were encountered an estimate was made of the approximate number of dragonflies present.

13.5.27 Counts were conducted between 10:00 and 16:00 hours during optimum weather conditions that comprise dry weather with an air temperature of above 17oC in the shade, with at least 50% sunshine and light wind conditions. Butterflies

13.5.28 Butterflies were surveyed concurrently with dragonflies, following the transect survey methodology and schedule detailed above (refer to Figure 13-5 for transect routes). The survey schedule takes advantage of peak butterfly activity that occurs in Hong Kong during May to June and September to October. Fish

13.5.29 The irrigation ditches present within the study site were surveyed for fish during May 2001. The sampling locations are shown in Figure 13-6. A 1cm mesh net was placed across the narrowest section of the drainage ditch. The surveyor subsequently walked downstream with exaggerated movements to direct the fish into the net. Fish disturbed were collected using hand nets and identified on site.

13.5.30 Bankside observations were also carried out at locations along the drainage ditch where the water was too deep to carry out efficient sampling. This survey method was also used in shallow, slow-flowing waters with limited instream or backside vegetation where fish could easily be seen.

13.5.31 The species of fish and their abundance were recorded. All individuals collected for identification were released at the place of capture as soon as possible. Specimens for which identification was uncertain were kept temporarily in fish tanks pending taxonomic verification; once identified, the specimens were released at their point of capture. Amphibians

13.5.32 Amphibians were surveyed along set transects T1 – T10 within the study site (Figure 13-5). Monthly amphibian surveys were undertaken at dusk over two consecutive days between April and October 2001. Incidental sightings of amphibians were also recorded during the daytime surveys for insects and reptiles.

13.5.33 Surveys were conducted for a fixed period from 18:30 to 20:30. The surveyor used a torch light to scan the aquaculture ponds, permanent streams, agriculture fields, reedbed, marsh and pools, and vegetation therein to spot amphibians. Day light surveys that were conducted along transects T1 to T10 to record reptile, butterflies and dragonflies were conducted for a set time duration from 10:00 to 16:00hrs.

13.5.34 All amphibians recorded were identified to species level, counted and where possible sexed. Reptiles

13.5.35 Reptile surveys were undertaken monthly between April and November 2001. The reptile


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population was surveyed along the same transect route as that used for the dragonfly and butterfly surveys (Figure 13-5). Reptiles were surveyed during daytime for a fixed time period of 10:00 – 16:00, during warm sunny weather, which are the optimum climatic conditions for reptiles. Opportunistic sightings of reptiles were also recorded during the amphibian surveys conducted at the site.

13.5.36 The surveyor walked along transects at a standard pace and actively searched out reptiles in likely basking spots and retreats (e.g. exposed sunny open patches of ground, abandoned materials, habitat edges, or areas shaded from direct sunlight such as under bushes or shrubs etc) and as far ahead along the transect as possible. For each reptile seen, the individual was identified to species level and the number of individuals counted recorded for each transect. The surveyor used close focusing binoculars to spot and identify reptiles to species level that were observed in the distance. Birds Transect surveys

13.5.37 The Mai Po Inner Deep Bay Ramsar Site is an important site for migrating and wintering wetland dependent birds. Furthermore, aquaculture ponds are known to be of considerable value as foraging habitat for birds, particularly when they are drained down (Aspinwall, 1997). Consequently significant survey effort was applied to surveying birds within the Assessment Area and a particular focus was placed on gathering information about the usage of specific ponds by birds throughout the year.

13.5.38 The bird survey methodology and data recording format duplicate those adopted by the Ramsar Site Waterfowl Monitoring Programme (Carey, G.J., undated). Each aquaculture pond present within the study site was allocated a unique reference number 1-103 (see Figure 13-1). Seven set transect routes (T1 – T7) were established to enable surveyors to visit and observe birds within each of the habitat types present (see Figure 13-7).

13.5.39 Transects T1-T5 which are located within wetland areas and transect T6 which is located in the scrubland, agricultural land, orchard and grassland located within the 500m buffer zone adjacent to the southern part of the study site were surveyed on foot. Transect T7, which encompasses a large area of habitats within the 500m buffer zone was surveyed from a slow moving vehicle that made frequent stops to allow accurate counts to be made. To coincide with peak bird activity, each survey was commenced one hour after dawn. Transects T1-T5 and T7

13.5.40 During surveys of these transects all birds were identified to species and associated information, such as weather conditions, habitat type and site condition were recorded on standard survey forms. Pond management practices and the status of vegetation growing on the bunds were also recorded. The species and abundance of birds observed flying over the study were also recorded if the surveyor was certain that these individuals had not previously been recorded during that particular visit.

13.5.41 Bird surveys were undertaken 2 to 3 times per month from January to December 2001. Aspinwall (1997) identified that waterbirds congregate at drained aquaculture ponds to feed on ‘trash fish’ exposed in shallow water. To assess the species and abundance of waterbirds that utilise drained ponds transects T1-T5 and T7 were surveyed three times per month during those months when aquaculture ponds were drained down (ie January, February, September, October and November). For the remainder of the year (i.e. March to August) transects T1-T5 and T7 were surveyed twice per month. Transect 6

13.5.42 Surveys of Transect 6 were particularly focused on passerine species associated with the complex mosaic of habitats present within this southern part of the assessment area. In addition to presence or absence of species, resident status in Hong Kong was assigned according to the following categories (Carey et al., 2001): • Breeding resident (R) • Passage migrant (M) • Spring migrant (SpM)


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• Summer breeding visitor (Su) • Autumn migrant (AM) • Winter visitor (W) • Possible winter visitor (?W) Flight line surveys

13.5.43 A survey of the flight lines of birds over the Assessment Area was undertaken as a separate exercise during the period January – December 2001. The specific objectives of the study were to identify any likely adverse ecological impacts that the proposed residential complex may have on bird flight paths, particularly in relation to species of conservation importance within three key groups of birds, listed below, and to identify any measures that could be taken to minimise impact on these bird groups, particularly in relation to building height and location. The key bird groups surveyed were: • “ardeids” – herons and egrets, • “raptors” – birds of prey, • “waterbirds” – ducks, cormorants and spoonbills.

13.5.44 During the twelve month period between January – December 2001, bird flight over the proposed development site was surveyed twice a month by a professional ornithologist from fixed vantage points situated on a hillside north of Ng Uk Tsuen (Figure 13-8). These vantage points were selected because they provide an unobstructed view over the entire Study Site and surrounding area.

13.5.45 Bird flight activity is known to be related to time of day so surveys were conducted during the periods immediately after sunrise and immediately before sunset, when activity is greatest and when there is sufficient light to allow identification. Morning and evening surveys were conducted on separate days during each month.

13.5.46 The duration of each survey was four (4) hours subdivided into eight (8) equal half-hour segments. A relative system was employed for the timing of surveys to compensate for changes in the time of sunrise and sunset through the seasons (see Table 13-2).

Table 13-2 Survey Time Segments for Bird Flight Line Surveys

Time period code Time segments Evening 1 Sunset minus 30-0 mins 2 Sunset minus 60-30 mins 3 Sunset minus 90-60 mins 4 Sunset minus 120-90 mins 5 Sunset minus 150-120 mins 6 Sunset minus 180-150 mins 7 Sunset minus 210-180 mins 8 Sunset minus 240-210 mins Morning 9 Sunrise plus 0-30 mins 10 Sunrise plus 30-60 mins 11 Sunrise plus 60-90 mins 12 Sunrise plus 90-120 mins 13 Sunrise plus 120-150 mins 14 Sunrise plus 150-180 mins 15 Sunrise plus 180-210 mins 16 Sunrise plus 210-240 mins


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13.5.47 During surveys all birds flying over the site were identified to species level. The individual flight lines of target species (defined in Table 13-3) were recorded on standard survey maps, uniquely referenced, and the following information recorded on cross-referenced data sheets:

• Reference number

• Survey date

• Survey period

• Species code

• Number of birds in the group (flocks of two or more birds often follow a similar route)

• Approximate altitude estimated by the observeer

Table 13-3 Target Species for Flightline Surveys and Their Species Codes used on Recording Sheets

Species Species code Ardeids Cattle Egret (Bubulcus ibis) CE Chinese Pond Heron (Ardeola bacchus) CPH Great Egret (Egretta alba) GE Grey Heron (Arda cinerea) GH Little Egret (Egretta garzetta) LE Black-crowned Night Heron (Nycticorax nycticorax) NH

Waterbirds Black-faced Spoonbill (Platalea minor) BFS Eurasian Spoonbill (Platalea leucorodia) ES Great Cormorant (Phalacrocorax carbo) GC Northern Pintail (Anas acuta) NP Spot-billed Duck (Anas poecilorhyncha) SD

Raptors Black Kite (Milvus migrans) BK Common Buzzard (Buteo buteo) CB Common Kestrel (Falco tinnunculus) CK Crested Serpent Eagle (Spilornis cheela) CSE Greater Spotted Eagle (Aquila clanga) GSE Imperial Eagle (Aquila heliaca) IE Osprey (Pandion haliaetus) OS

13.5.48 The observation locations are approximately 40m above ground level thus enabling the observer to gauge altitude. Nevertheless it was not considered feasible to estimate altitude accurately to less than 20m and so height categories of 20m interval were employed (Table 13-4Error! Reference source not found.). Landmarks along the horizon were also used to estimate the height at which the birds were flying across the Study Site.

Table 13-4 Altitude Categories Adopted to Record the Bird Flight Line Data

Altitude category Altitude 1 <20m 2 20-40m 3 40-60m 4 >60m


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13.5.49 The survey data were manually geo-coded into a GIS (MapInfo Ver. 6) and the following attributes input for each individual flightline: • Species • Altitude category (except for data collected during January 2001) • Date and time period code • Number of birds in the group

13.5.50 For analytical purposes, the survey data were aggregated into months (Jan, February, March etc.).

13.5.51 Flight line data were geo-coded and overlaid onto digitised base maps of the Study Site.

13.5.52 The GIS package was interrogated to identify the species composition and abundance of birds flying over any sector (or all) of the Study Site for any (or all) altitude categories and for any (or all) months. On the basis of these data it was possible to compare the species composition and abundance of birds flying through the sector occupied by the Proposed Development Area and to compare these to similar data for the entire study area or any other sector of the study area.

13.5.53 Specific analyses focused on a describing the absolute and relative abundance of target species flying across, within, into or out of the Study Site and, in particular, the specific sector of the Study Site that would be occupied by the proposed residential development Mammals

13.5.54 Mammals were surveyed concurrently during reptile and amphibian surveys along the set transect routes shown in Figure 13-5.

13.5.55 Mammals were surveyed monthly during the day and at dusk from April to November. As they are elusive species any evidence of their presence including the presence of scats, tracks and feeding were also recorded. Relevant data of sightings of mammals were recorded on standard survey forms.

13.6 General Ecological Profile and Evaluation of Valued ecological Components

Habitats 13.6.1 On the basis of the literature review, interpretation of aerial photographs, site inspections and

flora and fauna surveys, the ecological resources and receivers that may be affected by the development were identified. Amongst these the Valued Ecological Components (VECs) (Treweek 1999), both habitats and Species of Conservation Importance, have been determined following the guidelines for the evaluation of ecological importance of habitats and species given in the Technical Memorandum on Environmental Impact Assessment Process (EPD). Introductory Overview of Broad Habitat Types

13.6.2 The Study Site (as defined in Section 13.1.2) is composed almost entirely of aquaculture ponds (fishponds that are actively managed, those that are currently unmanaged, and the intervening bunds). The 500m buffer zone around the Study Site contains a greater variety of habitat types including, Feng Shui woodland, permanent natural freshwater habitats and mangrove stands, although aquaculture ponds remain the dominant habitat type.

13.6.3 Based on interpretation of recent aerial photographs, existing data and site inspections 19 distinct habitat types were categorised on the basis of their botanical composition and physical and structural characteristics: • Intertidal forested wetlands – mangrove stands • Permanent rivers, streams and creeks – natural flowing freshwater habitats • Ditches and drainage channels – artificial ditches, drainage channels and nullahs • Aquaculture pond – fishponds bound by vegetated bunds; some managed for commercial

aqua-culture production, others where no management facilities were observed in the immediate vicinity of the pond

• Reedbed • Permanent freshwater marsh and pools – flooded areas comprising a mix of water-dependent

plants


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• Seasonally flooded agricultural land – includes intensively managed wet agricultural land • Dry agricultural land – agricultural land on which a range of food crops and flowers are

cultivated • Inactive agricultural land – fallow or abandoned agricultural land which is un-managed and

has been invaded by herbaceous or shrubby vegetation • Orchard – patches of fruit trees mainly found scattered among rural village areas • Fung-shui forest – forest found around rural villages comprising native species or a mix of

native species and fruit trees • Semi-natural secondary woodland – woodland formed from a mixture of planted and native

species, moderately disturbed by human activity • Plantation forest – landscaping or ornamental plantations mainly found along roads and on

cut-slopes • Grassland – habitats dominated by grass and herbaceous species • Grassland-shrubland mosaic – undisturbed areas with grassland comprising 80% of cover • Landscaped area – areas managed intensively for landscape or amenity purposes • Works in progress • Wasteland – secondary vegetative colonisation (mainly grasses and ruderals) on areas opened

by human activities (excluding those grown on inactive agricultural land) • Developed area – areas highly developed with no visible vegetation cover except road-side

weeds and includes a wastewater treatment works and associated water storage area

13.6.4 The distribution of these habitat types within the Assessment Area is illustrated in Figure 13-9. Representative photographs of each habitat type are included in Appendix 13-2. Their respective coverage within the different sectors of the study area is quantified in Table 13-5 below.

Table 13-5 Extent of Habitat Types within the Assessment Area (ha.)

Habitat 1. Proposed Development Area

2. Wetland Nature Reserve

3. Study site (1 + 2)

4. 500m buffer zone

5. Assessment Area (3 + 4)

Intertidal forested wetlands 0 0 0 45.3 45.3 Permanent rivers, streams and creeks

0 0 0 25.2 25.2

Ditches and drainage channels

0 0.4 0.4 0.4 0.8

Aquaculture pond 4.0 75.7 79.7 90.1 169.8 Reedbed 0 0 0 0.4 0.4 Permanent freshwater marsh and pools

0 0 0 2.8 2.8

Seasonally flooded (wet) agricultural land

0 0 0 1.7 1.7

Dry agricultural land 0 0 0 0.2 0.2 Inactive agricultural land 0 0 0 5.2 5.2 Orchard 0 0 0 1.4 1.4 Fung-shui woodland 0 0 0 1.3 1.3 Semi-natural secondary woodland

0 0 0 18.4 18.4

Plantation woodland 0 0 0 3.0 3.0 Grassland 0 0 0 4.2 4.2 Grassland – shrubland mosaic

0 0 0 20.5 20.5

Landscaped area 0 0 0 8.8 8.8 Works in progress 0 0 0 37.1 37.1 Wasteland 0 0 0 13.5 13.5 Developed area 0 0 0 61.9 61.9 TOTAL 4.0 76.1 80.1 341.4 421.5


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13.6.5 The Proposed Development Area and the area of the proposed Wetland Nature Reserve are dominated by Aquaculture Ponds. The bunds associated with these ponds have an infrastructure associated with fishpond operation (houses, sheds, power lines, unmade tracks, duck shelters etc.). There are also a limited network of Ditches and Drainage Channels.

13.6.6 The habitats surrounding this central core of fishponds (ie within the 500m Buffer Zone) are more diverse. In the southern part of the Buffer Zone there is a mosaic of wet and dry agricultural land (Seasonally Flooded Agricultural Land, Dry Agricultural Land and Inactive Agricultural Land) interspersed with naturally regenerating Freshwater Marsh and Reedbed that is functionally linked to the aquaculture ponds to the north. Also within this southern area, particularly on higher ground, there are semi-natural habitats of Grassland and Grassland-Shrubland Mosaic. Habitats dominated by woody species include Plantation Woodland, Orchard and Fung-shui Woodland. The remainder of the southern part of the buffer zone is occupied by highly disturbed habitats such as Wasteland and Developed Area associated with residential and industrial land-uses.

13.6.7 The northern part of the 500m Buffer Zone is dominated by Aquaculture Ponds, which beyond the limit of reclamation, give way to extensive Inter-Tidal Forested Wetlands (mangroves) and beyond the Assessment Area boundary, inter-tidal mudflat.

13.6.8 The eastern and western parts of the Assessment Area are bounded by permanent watercourses (Permanent Rivers, Streams and Creeks) which potentially provide opportunity for linkage to habitats over a wider geographical area. This capacity is severely limited, however, due to their highly degraded state.

13.6.9 Following the guidelines in Appendix 8 of the Technical Memorandum on Environmental Impact Assessment Process (EPD), the habitats of the Assessment Area are individually evaluated below with specific reference to their conservation value. Habitat Evaluations Intertidal Forested Wetlands

13.6.10 The northern part of the Assessment Area (500m Buffer Zone) is marine in character and extensive mangroves have developed in inter-tidal areas. Although patches of intertidal mudflat remain, the dominant vegetation is mangroves and for the purposes of this assessment this habitat has been considered collectively as mangrove. The ecological value of this habitat is evaluated in Table 13-6.

Table 13-6 Ecological Evaluation Of Intertidal Forested Wetlands

Criteria Intertidal forested wetlands

Naturalness This habitat comprises naturally regenerating mangrove forest interspersed with uncolonised mudflat, mangroves are expected to colonise remaining mud-flat areas in coming years

Size (ha) Relatively large; 45.3ha within the Assessment Area, none within the proposed Development Area or proposed WNR area

Diversity Mangroves possess a diverse range of micro-habitats and species

Rarity Common feature of inter-tidal zones in Hong Kong

Re-creatability Low re-creatability

Fragmentation Not fragmented (probably expanding in area)

Ecological linkage Linked to other areas of mangroves in the Deep Bay area

Potential value Unlikely to achieve significantly greater value

Nursery and breeding ground High, breeding ground for many marine invertebrate species

Age Unknown

Abundance/ Richness of wildlife High

Conclusion* Moderate to high

* Low, moderate or of high ecological value


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Permanent Rivers, Streams And Creeks

13.6.11 This habitat type is restricted to two relatively large and very disturbed water courses. The Eastern main Drainage Channel in the eastern part of the Assessment Area and Tai River outfall in the west. The ecological value of these water courses is diminished due to extensive modifications to their banks and the very poor quality of the water flowing within them. The ecological value of this habitat is evaluated in Table 13-7.

Table 13-7 Ecological Evaluation of Permanent Rivers, Streams and Creeks

Criteria Permanent rivers, streams and creeks Naturalness Highly disturbed: water quality is poor and there have been

extensive modifications to banks and riparian zone Size (ha) Approx. 25 ha. Within the Assessment Area, 0 ha within the

Proposed Development Area or proposed WNR area Diversity Considered low in both habitat and species diversity Rarity This habitat is not considered to be rare and no rare species were

recorded Re-creatability Readily re-creatable Fragmentation Not fragmented Ecological linkage Although watercourses can act as corridors for the dispersal of

plant and animal species the ecological linkage of this habitat is considered to be low because of its highly modified and disturbed condition

Potential value Could be higher subject to water quality improvements. Potential value is limited, however, due to bank modifications

Nursery and breeding ground Not considered significant Age No information but considered irrelevant Abundance/ Richness of wildlife Poor Conclusion* Low

* Low, moderate or of high ecological value Ditches and Drainage Channels

13.6.12 Four drainage ditches were identified within the Assessment Area. Used for translocating water between fishpond areas, these ditches have low intrinsic value for flora and fauna, but do provide some linkage between habitats. The ecological value of this habitat is evaluated in Table 13-8.

Table 13-8 Ecological Evaluation of Ditches and Drainage Channels

Criteria Ditches Naturalness Artificial habitat Size (ha) Approx. 0.8 ha. Within the Assessment Area, 0.4 ha within the

Proposed Development Area and proposed WNR area Diversity Considered low in both habitat and species diversity Rarity This habitat is not considered to be rare and no rare species were

recorded Re-creatability Readily re-creatable Fragmentation Not fragmented Ecological linkage Very limited but does provide some linkage between some

ponds in the western part of the proposed Wetland Nature Reserve and the Tai River outfall.

Potential value Could be higher subject to water quality improvements Nursery and breeding ground Not considered significant Age No information but considered irrelevant Abundance/ Richness of wildlife Poor Conclusion* Low


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* Low, moderate or of high ecological value Aquaculture Ponds

13.6.13 The dominant land-use within the Assessment Area is aquaculture. This area consists of a matrix of fishponds bounded by vegetated bunds, which is considered in this assessment as a complex of functionally related habitats. The man-made bunds link fishponds to one another and to adjacent terrestrial habitats. Bunds are a disturbed habitat type but provide roosting areas and refuge for some bird species that forage in fishponds. Actively managed aquaculture ponds are of higher ecological value than unmanaged aquaculture ponds because they support more abundant prey and periodic draw-down allow birds to access prey.

Table 13-9 Ecological Evaluation of Aquaculture Ponds

Criteria Aquaculture ponds Naturalness Man-made habitat; Actively managed for fish production are

the least natural but tend to support a higher diversity and abundance of birds

Size (ha) 169.8 ha in Assessment Area of which 79.7 ha is within the Study Site. Of this 4 ha is found within the Development Area. Forms part of an extensive, contiguous block of aquaculture ponds within the Fung Lok Wai Assessment Area that is itself closely linked to fishpond areas in the Deep Bay Area, including Mai Po; Active aquaculture is more dominant within the Assessment Area

Diversity Low habitat diversity but very high in terms of the diversity of wildlife supported; Unmanaged ponds tend to support fewer individuals

Rarity The habitat itself is not rare but some of the species supported are rare locally or globally, notably some avifauna

Re-creatability Readily re-creatable Fragmentation Not fragmented Ecological linkage Part of the large contiguous area of fishpond habitat in the

Deep Bay area and serves similar function to those located at Mai Po Nature Reserve

Potential value High ecological potential if managed to enhance wildlife use Nursery and breeding ground Actively managed ponds are a highly productive system that

are particularly important for the high densities of important food resources provided for birds during draw-down for harvest periods. Inactive ponds tend to be less valuable than active, but they do provide an important breeding/nursery ground for the prey of bird and other mammals, notably Tilapia and chironomids; Bunds provide a breeding ground for some passerines and numerous terrestrial invertebrates

Age Probably less than 40 years. This issue is, in any event, considered irrelevant to the ecological value of this habitat type

Abundance/ Richness of wildlife High Conclusion* High


Reedbed

13.6.14 Reedbed habitat is restricted to a small area, probably an abandoned fishpond in the southern part of the assessment area. The area is small and densely occupied by Phragmites. Whilst this area may provide cover for some species (eg birds) its small size and dense growth limits its overall value. Small stands of reeds associated with ditches are considered under Ditches and drainage channel as they form part of the characteristic vegetation of that habitat type (see Table 13-10)


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Table 13-10 Ecological Evaluation of Reedbed

Criteria Reedbed Naturalness This is naturally regenerating habitat within an artificial fishpond Size (ha) Total of 0.4 ha within the Assessment Area in several small blocks. Diversity Both species and habitat diversity are considered low Rarity Neither the habitat nor the species found are considered rare Re-creatability Highly re-creatable Fragmentation Highly fragmented, only one small area recorded within the

Assessment Area Ecological linkage Links ponds in the Fung Lok Wai Study Site and wet habitats in

the southern part of the Assessment Area. Potential value Moderate potential value - would be higher if actively managed as

wildlife habitat Nursery and breeding ground Part of the Fung Lok Wai wetland system and probably providing

habitat for breeding invertebrates that form the foods source of larger animals such as birds and amphibians

Age No information is available but the size and density of reed growth (at the time of the survey) suggests that it was more than 5 years old

Abundance/ Richness of wildlife Low Conclusion* Low


Permanent Freshwater Marsh and Pools

13.6.15 Areas of marsh occur in the southern part of the Assessment Area in close association with various agricultural land-uses. It is likely that these areas of marsh have formed on land previously used for aquaculture or wet agriculture (see Table 13-11).

Table 13-11 Ecological Evaluation of Permanent Freshwater Marsh and Pools

Criteria Permanent freshwater marsh and pools Naturalness The marsh community appears natural but has probably developed on

agricultural fields or ponds that have become inactive Size (ha) Total of 2.8 ha within the Assessment Area in several small to moderate

sized blocks Diversity Species and habitat diversity are considered moderate and low respectively Rarity Neither the habitat nor the species found are considered rare Re-creatability This habitat is readily re-creatable provided land is available Fragmentation Fragmented Ecological linkage Part of the wetland systems of the Fung Lok Wai and the Deep Bay area as

a whole Potential value Moderate potential value - would be higher if actively managed as wildlife

habitat Nursery and breeding ground

Likely to provide a nursery/breeding ground for the invertebrates which serve as an important food item to insectivorous fauna

Age No information is available, but species diversity and plant age (at the time of the survey) suggests that this marsh was over 5 years old.

Abundance/ Richness of wildlife

Moderate

Conclusion* Low to Moderate * Low, moderate or of high ecological value

Agricultural Land

13.6.16 Agricultural land is found within the southern part of the Assessment Area within the 500m Buffer Zone. Various type of agricultural land are present and these have been distinguished on the type and intensity of management in Table 13-12 - Table 13-14.


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Table 13-12 Ecological Evaluation of Seasonally Flooded (wet) Agricultural Land Criteria Wet agriculture Naturalness Man-made habitat actively managed for crop production Size (ha) Total of 1.7 ha within the Assessment Area in several moderate sized

blocks Diversity Habitat diversity is low but diverse invertebrate and vertebrate fauna are

supported Rarity The habitat type is not rare in Hong Kong, but is declining rapidly, with

few large areas remaining. A number of rare bird species are known to utilise this habitat type as feeding/roosting sites, including Northern Hobby

Re-creatability It is readily re-creatable provided that land is available Fragmentation The areas of this habitat are slightly fragmented but lie in close

proximity in the southern part of the Assessment Area Ecological linkage Forms part of a mosaic of wet and dry land-uses in the southern part of

the Assessment Area. Functionally linked to the broader Fung Lok Wai area

Potential value High potential if ecologically sensitive management practices are retained or adopted

Nursery and breeding ground


Age No information is available and this criteria is considered irrelevant to the ecological value of active wet agricultural land


Moderate

Conclusion* Moderate * Low, moderate or of high ecological value

Table 13-13 Ecological Evaluation of Dry Agricultural Land

Criteria Dry agricultural land Naturalness Man-made habitat actively management for crop production Size (ha) Total of 0.2 ha within the Assessment Area in several small blocks Diversity Low to moderate in habitat diversity and species diversity due to the

diversity of food crops planted. Rarity The habitat type is not rare in Hong Kong, but a number of rare birds are

known to use this type of habitat for feeding and/or roosting. Re-creatability Readily re-creatable provided that land is available Fragmentation Highly fragmented Ecological linkage Forms part of a mosaic of wet and dry land-uses in the southern part of


Potential value Dry agricultural land could be managed to promote wildlife use by adopting management practices that enhance habitat heterogeneity; however, this may conflict with commercially driven crop production



Age No information is available and this criteria is considered irrelevant to the ecological value of active dry agricultural land


Low


Table 13-14 Ecological Evaluation of Inactive Agricultural Land

Criteria Inactive agricultural land Naturalness Man-made habitat Size (ha) Total of 5.2 ha within the Assessment Area in several small to moderate

sized blocks


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Diversity Habitat diversity is moderate but supports diverse species Rarity The habitat type is not rare in Hong Kong, but a number of rare avifauna

species have been reported from these areas Re-creatability Readily re-creatable Fragmentation Highly fragmented Ecological linkage Forms part of a mosaic of wet and dry land-uses in the southern part of


Potential value Abandoned agricultural land could be managed to promote wildlife use by adopting management that aims to enhance habitat heterogeneity



Age No information is available Abundance/ Richness of wildlife

Low


Orchards

13.6.17 Orchards are found within the southern part of the Assessment Area and comprise a variety of fruiting tree species often planted in association with other native and introduced tree and shrub species (see Table 13-15).

Table 13-15 Ecological Evaluation of Orchards

Criteria Orchards Naturalness Man-made habitats Size (ha) Total of 1.4 ha within the Assessment Area in several small to

moderate sized blocks Diversity Both the habitat diversity and species diversity are low Rarity Neither the habitat nor the species found are rare Re-creatability This habitat type is readily re-creatable Fragmentation Heavily fragmented Ecological linkage May provide movement corridor for wildlife using the

surrounding area Potential value Poor in potential value as they are close to settlements and

subject to high levels of disturbance Nursery and breeding ground No wildlife of conservation importance is expected Age Age varies depending on how recently planted. Presence of

mature tress suggests significant age in some cases Abundance/ Richness of wildlife Low Conclusion* Low

* Low, moderate or of high ecological value Fung Shui Woodland

13.6.18 A single Fung shui woodland has been identified in the southern part of the Assessment Area. The occupation by breeding egrets during the four seasons ecological survey had increased the conservation value of this small woodland area, however, recent observation indicates that this egretry is now abandoned (eg. Anon 2005) (see Table 13-16).

Table 13-16 Ecological Evaluation of Fung Shui Woodland

Criteria Fung shui Woodland Naturalness Natural habitat but typical modifications by villagers limit value Size (ha) Total of 1.3 ha within the Assessment Area in a small block Diversity Structurally simple and species poor Rarity Fung shui woodlands are common, traditional feature of village areas

in the New Territories. This example is rare because during the baseline surveys it supported an active egretry (now abandoned)

Re-creatability Habitat characteristics are difficult to recreate Fragmentation Small isolated example although linked to other habitats


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Ecological linkage Connected to other woody habitats and adjacent to aquaculture ponds where ardeid species forage

Potential value Limited due to village development in the surrounding area Nursery and breeding ground Breeding egrets Age The size of the trees indicates an age of over 50 years Abundance/ Richness of wildlife

Low-Moderate

Conclusion* With Egretry this habitats has High Ecological Value without the Egretry its value is considered to be of Low to Moderate Ecological Value

* Low, moderate or of high ecological value Semi-natural Secondary Woodland

13.6.19 Secondary woodland areas are concentrated on the lower hillsides in the southern part of the Assessment Area. These areas are semi-natural and fragmented (see Table 13-17).

Table 13-17 Ecological Evaluation of Semi-natural Secondary Woodland

Criteria Semi-natural secondary woodland Naturalness Semi-natural but with some modification and planting of non-

native species Size (ha) Total of 18.4 ha within the Assessment Area in several moderate

sized blocks Diversity Low in habitat diversity, moderate in species diversity Rarity Neither the habitat nor associated species are rare Re-creatability This habitat type is readily re-creatable Fragmentation Slightly fragmented Ecological linkage May provide movement corridors for wildlife Potential value High, if disturbance factors were removed. Nursery and breeding ground No wildlife of conservation importance Age Young to moderate Abundance/ Richness of wildlife Low to moderate Conclusion* Low to moderate


Plantation woodland

13.6.20 Two small areas of plantation woodland were recorded within the Assessment Area, both are dominated buy non-native and exotic species (Table 13-18).

Table 13-18 Ecological Evaluation of Plantation Woodland

Criteria Plantation woodland Naturalness Planted with predominantly non-native and exotic species Size (ha) Total of 3.0 ha within the Assessment Area in several small to

moderate sized blocks Diversity Low in habitat diversity, moderate in species diversity Rarity Neither the habitat nor associated species are rare Re-creatability This habitat type is readily re-creatable Fragmentation Not fragmented Ecological linkage Low Potential value Low due to non-native species planted but succession could

increase value Nursery and breeding ground No wildlife of conservation importance Age Young to moderate Abundance/ Richness of wildlife Low to moderate Conclusion* Low

Grassland

13.6.21 Small pockets of grassland were recorded across the Assessment site, primarily adjacent to the closed area boundary road (Table 13-19).


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Table 13-19 Ecological Evaluation of Grassland

Criteria Grassland Naturalness Natural regeneration, probably on disturbed areas. Subject to

ongoing disturbance, including fire Size (ha) Total of 4.2 ha within the Assessment Area in several small

blocks Diversity Low habitat and species diversity Rarity Neither habitat nor species recorded are rare Re-creatability Highly re-creatable Fragmentation Highly fragmented Ecological linkage Serves limited function as a link between other habitats, however,

proximity to developed and disturbed habitats limits this function Potential value Low due to ongoing disturbance effects Nursery and breeding ground May contribute to invertebrate food resource for larger animals of

the Assessment Area Age Not known but likely to be recent regeneration on previously

disturbed land Abundance/ Richness of wildlife Low Conclusion* Low

* Low, moderate or of high ecological value Grassland-shrubland mosaic

13.6.22 Grassland-shrubland mosaic habitat is associated with the hills in the southern part of the Assessment Area. Although it forms a linked habitat with areas of woody habitat, this habitat is subject to occasional burning through hill fires and hence its diversity and value are limited (Table 13-20).

Table 13-20 Ecological Evaluation of Grassland-Shrubland Mosaic Criteria Grassland-shrubland mosaic Naturalness Natural habitat but subject to hill-fire Size (ha) Total of 20.5 ha within the Assessment Area in several moderately

sized blocks Diversity Low habitat and species diversity is found in this habitat Rarity Neither the habitat nor the species known to be present are

considered rare Re-creatability Readily re-creatability Fragmentation Not fragmented within the Assessment Area Ecological linkage Linked to other woody habitats within the Assessment Area and

may provide cover for animal movements Potential value Moderate ecological potential if hill-fires can be controlled Nursery and breeding ground None known Age Unknown. Fire disturbance tends to maintain the habitat in early

successional stages and prevents establishment of woodland Abundance/ Richness of wildlife Poor Conclusion* Low

* Low, moderate or of high ecological value Landscaped area

13.6.23 The main section of landscaped vegetation occurs in the eastern part of the Assessment Area adjacent to the closed area boundary road. The major vegetation associated with this habitat is intensively managed grass turf (Table 13-21).

Table 13-21 Ecological Evaluation of Landscaped Area

Criteria Landscaped area Naturalness Man made and intensively managed Size (ha) Total of 8.8 ha within in the Assessment Area in a relatively

large block Diversity Very low Rarity No rare habitats or species


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Re-creatability Highly re-creatable Fragmentation Not fragmented Ecological linkage Creates a barrier between the wetland habitats of the

Assessment Area and the potential corridor of the Eastern Drainage Channel

Potential value None Nursery and breeding ground None known Age Young, created during the drainage works conducted on the

Eastern Main Drainage Channel. Abundance/ Richness of wildlife Very low Conclusion* Low

* Low, moderate or of high ecological value Wasteland habitats

13.6.24 Several categories of land that has been highly disturbed including areas of wasteland and where ponds have been in-filled. Due to the nature of the disturbance, including clearance and compaction, vegetation may be absent or in the form of poorly developed communities dominated by ruderal species (Table 13-22).

Table 13-22 Ecological Evaluation of Wasteland Habitats Criteria Wasteland Aquaculture ponds

(infilled) Naturalness This is a man made habitat

with little or no intrinsic ecological value

This is a man made habitat with little or no intrinsic ecological value

Size (ha) Moderate; 13.5 ha Small Diversity Not relevant Not relevant Rarity Not relevant Not relevant Re-creatability Readily re-creatable Readily re-creatable Fragmentation Not relevant Not relevant Ecological linkage Not relevant Not relevant Potential value None None Nursery and breeding ground

Not considered significant Not considered significant

Age No information but considered irrelevant

No information but considered irrelevant


Poor Poor

Conclusion* Low Low * Low, moderate or of high ecological value

Recreated Wetland (Hong Kong Wetland Park)

13.6.25 During the assessment period there was an area of land in the western part of the assessment area that was identified as Recreated Wetland. This area comprises wetlands and other habitats forming part of the Hong Kong Wetland Park. The Hong Kong Wetland Park is a man-made wetland consisting of 60 hectares of re-created habitats specially designed for waterfowls and other wildlife. Located on the western side of the Assessment Area, the Wetland Park was originally intended to be an ecological mitigation area (EMA) to compensate for the wetlands lost due to Tin Shui Wai New Town development. The original EMA has now been expanded to become a conservation, education and tourism facility. During the assessment period these habitats were under construction, followed by a period of establishment, and their ecological value was, therefore, at the time of the baseline surveys considered to be low. The works have now been completed and the site has been in operation since May 2006. The value of the wetland habitats at the Wetland Park will increase with time and it is anticipated they will become High in the lifetime of the Fung Lok Wai project. As indicated in Table 13-23 these habitats have been evaluated as Moderate – High.

Table 13-23 Ecological Evaluation of Recreated Wetland Criteria Hong Kong Wetland Park Naturalness Man made natural habitat, subject to


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human disturbance through tourism Size (ha) 60 ha Wetland area, 1 ha Visitor Centre Diversity High Rarity High Re-creatability Re-creatable Fragmentation Not fragmented Ecological linkage Potentially high as this area is close to

the proposed Fung Lok Wai WNR Potential value High Nursery and breeding ground Not significant record Age Young Abundance/ Richness of wildlife

High

Conclusion* Moderate - High * Low, moderate or of high ecological value

Developed areas

13.6.26 The southern part of the Assessment Area includes a variety of heavily developed land-uses, including Proposed Development Areas, and industrial estate, wastewater treatment and water storage areas. Typically these have very low intrinsic ecological value. Those species that do occur tend to be very common, introduced species or pests (Table 13-24).

Table 13-24 Ecological Evaluation of Developed Areas

Criteria Developed area Wastewater treatment area

Water storage area

Naturalness This is a man made habitat with little or no intrinsic ecological value



Size (ha) Large Moderate Small Diversity Not relevant Not relevant Not relevant Rarity Not relevant Not relevant Not relevant Re-creatability Readily re-creatable Readily re-creatable Readily re-creatable Fragmentation Not relevant Not relevant Not relevant Ecological linkage Not relevant Not relevant Not relevant Potential value None None None Nursery and breeding ground

Not considered significant

Not considered significant Not considered significant

Age No information but considered irrelevant




Poor Poor Poor

Conclusion* Low Low Low * Low, moderate or of high ecological value

Conclusions

13.6.27 The outcomes of the individual habitat evaluations are summarised in Table 13-25. It can be seen that the most valuable habitat components of the Assessment Area are wetland habitats. In particular the extensive block of Aquaculture Ponds (fishponds that are actively managed, those that are currently unmanaged, and the intervening bunds) that form a large contiguous area embedded within the broader Deep Bay Area that includes Mai Po. Adjacent to this central fish pond area there is, in the southern part of the Assessment Area, a mosaic of other wetland habitats including wet agriculture, marshland and reedbeds. Whilst these areas are of less intrinsic ecological value, their close proximity and functional linkage with the main fish pond area enhances their overall status.

13.6.28 The egretry in the small Fung-shui Woodland also in the southern part of the Assessment Area was also a feature of high ecological value due to the scarcity of active egretries in the New Territories. However, recent evidence suggests that it is abandoned (see Anon 2005); it is of a


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low to moderate ecological value.

13.6.29 The key ecological value of the Assessment Area is, therefore, the habitat it provides for breeding and foraging birds, particular wetland birds such as herons and egrets. Traditional aquaculture and agricultural management practices have, to a large extent, engendered this value. At the same time, however, these practices also limit the potential value of these habitats. Aquaculture ponds are for example small and steep sided which restricts bird access and pond bunds are cleared to maintain access to ponds. With more sympathetic management the value of the wetland habitats at Fung Lok Wai could be significantly higher.

13.6.30 The extensive area of inter-tidal habitat in the northern part of the Assessment Area is also of moderate to high ecological value due to the high biological diversity of mangal systems. There is no direct link between these habitats and the Proposed Development Area, however, and the potential for impact is very low.

13.6.31 All other habitats within the Assessment Area are considered to have low ecological value due, primarily to previous and current levels of disturbance.

Table 13-25 Summary of habitat evaluations in order of ecological value.

Habitat Overall evaluation Aquaculture ponds High Fung-shui woodland With egretry Without egretry

High

Low to Moderate Recreated Wetland (Hong Kong Wetland Park) Intertidal forested wetlands

Moderate to high Moderate to high

Agricultural land Seasonally flooded agricultural land Dry agricultural land Inactive agricultural land

Moderate

Low to moderate Low to moderate

Permanent freshwater marsh and pools Low to moderate Semi-natural secondary woodland Low to moderate Permanent rivers, streams and creeks Low Reedbed Low Ditches and drainage channels Low Wasteland Wasteland Aquaculture ponds (infilled)

Low Low

Grassland Low Grassland-shrubland mosaic Low Orchard Low Plantation forest Low Landscaped area Low Developed areas Developed area Wastewater treatment area Water storage area

Low Low Low

Species of Conservation Importance

13.6.32 Following guidance given in Annex 16 (Note 3) of the EPD's Technical Memorandum on Environmental Impact Assessment, species have been identified that are considered to be Species of Conservation Importance. These are defined as species that occurred within the Study Site in significant numbers and are: • Globally threatened (IUCN 2000, Collar et al. 1994) or threatened in China (Endangered

Species Scientific Commission 1998). • Internationally Protected Species, i.e. protected by international conventions: (1) The

Convention on the Conservation of Migratory Species of Wild Animals (the Bonn Convention), (2) listed under an agreement between the Government of Australia and the Government of the People’s Republic of China for the Protection of Migratory Birds and their Environment, (3) listed under an agreement on the Protection of Migratory Birds and their Habitats between the Government of Japan and the Government of the People’s


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Republic of China. • Protected by Hong Kong legislation and guidelines: (1) The Forests and Countryside

Ordinance (Cap. 96), (2) The Forestry Regulations (subsidiary legislation of Cap. 96), (3) The Wild Animals Protection Ordinance (Cap. 170), (4) Protection of Endangered Species of Endangered Species of Animals and Plants Ordinance (Cap. 586), (5) The Fisheries Protection Ordinance (Cap. 171), (6) The Fisheries Protection Regulations (subsidiary legislation of Cap. 171).

• Protected by Chinese laws and regulations: (1) The Wildlife Protection Law of the PRC, (2) The Wildlife Protection Implementation Regulation of the PRC.

• Note: All birds and bats are listed in the Wild Animals Protection Ordinance primarily as protection from hunting, persecution and trade etc. Therefore, only those that meet other criteria listed here or are Locally Important Species according to criteria listed below are considered to be Species of Conservation Importance.

• Endemic to Hong Kong or south China; if they are rare in the territory or have special conservation importance according to other scientific studies, e.g. for birds if they are of international importance (i.e. >1% of the biogeographical population) or regional importance (as listed in the Deep Bay Ramsar Conservation Strategy (Aspinwall Clouston & Wetlands International - Asia Pacific, 1997).

• Based on the above criteria and Fellowes et al. (2002), species that occurred within the Assessment Area identified as being of conservation importance are further subdivided into categories of global, regional or local conservation importance. Although these species include some that are reasonably widespread in Hong Kong they are considered important in sustaining the long-term biodiversity of the territory.

Plants

13.6.33 For each habitat type surveys were conducted to determine species composition and relative abundance. The results of these surveys are included in Appendix 13-3.

A total of 326 plant species were recorded within all habitats of the assessment area. Off these 206 are native to Hong Kong, and most are common and widespread. No plant Species of Conservation Importance were recorded in significant numbers at the site. However, four plant species of conservation interest were recorded, within five different habitats (Table 13-26).

Table 13-26 Plant Species of Potential Conservation Interest Recorded within the Assessment Area

Plant species Status within Hong Kong1

Regional distribution and protected status

Recorded abundance

Habitat

Ammannia auriculata

Very rare Regionally widespread

Occasional Watercourse

Aquilaria sinensis Common Class 2 in China Occasional Woodland and orchard

Phymatodes scolopendria*

Rare Scarce Aquaculture Pond (bunds)

Sphenoclea zeylanica

Rare Scarce Wet Agriculture

1 Based on Corlett et al. (2000). * Previously Microsorium scolopendrium

13.6.34 None of these species is common within the assessment area, with two (Phymatodes scolopendria and Sphenoclea zeylanica) recorded only from single specimens. Ammannia auriculata is locally rare but regionally widespread in south China and a known pan-tropical weed. It was located within Ditches and drainage channels habitat which is typical habitat for this species. Aquilaria sinensis is protected (Category III) in China and listed as VU on IUCN red data list. It is, however, a common tree in Hong Kong where its natural status is difficult to determine as it is widely cultivated. Phymatodes scolopendria is usually a species of rocky shores. At Fung Lok Wai it was recorded at the edge of a pond which was no longer actively


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managed and is likely to be a remnant of previously cultivated plants. Sphenoclea zeylanica is rare in Hong Kong and typically found in abandoned paddy fields and wasteland. Within this survey it was located in a wet agricultural area in the southern part of the Assessment Area outside the Proposed Development Area.

13.6.35 None of the above species are protected under Hong Kong legislation. Only one Aquilaria sinensis could be considered a species of Conservation Importance under the criteria outlined in the EIAO –TM. However, this species is common in Hong Kong and likely to be a cultivated variety. Aquatic Invertebrates

13.6.36 Surveys of aquatic invertebrates reveal a highly depauperate fauna (Appendix 13-4). Commonly sampled aquatic invertebrates include Dipteran species such as the ubiquitous Chironominae spp. and crustaceans such as Palaemonid shrimps. Infrequent gastropods were also sampled, particularly in watercourses. The dominant species are typical of disturbed aquatic habitats, such as fishponds and drainage ditches.

13.6.37 The absence of water of high quality and the lack of flowing habitats clearly limits the value of the site for aquatic invertebrates. Although diversity is low, the abundance of Chironomids and Palaemonid shrimps is significant, however, because they form a valuable source of food for other fauna, particularly birds.

13.6.38 Analysis of the variance of sampled populations (sweep and core) of these groups throughout the site and during wet and dry seasons, indicates that although there is significant variability between locations, these invertebrates collectively provide a reliable food source around the year. Odonata

13.6.39 Twenty-six species of dragonflies and damselflies were recorded during surveys within the Fung Lok Wai EIA Assessment Area (see Appendix 13-5), approximately 23% of the known dragonfly fauna of Hong Kong (Wilson 1997). These species are all common and widespread. Two species previously considered to be of Local Conservation Concern (Fellowes et al. 2002), Potamarcha congener and Urothemis signata signata, are known to be widespread in Hong Kong (Wilson et al. 2004).

13.6.40 Brachythemis contaminata, Ischnura senegalensis, Orthetrum sabina sabina, Pantala flavescens and Rhyothemis variegata aria are the most frequently recorded species collectively accounting for over 60% of all dragonflies recorded during the surveys.

13.6.41 Potamarcha congeneri was recorded on only one occasion in the vicinity of the access track (Transect 3) in the western part of the Buffer Zone. Urothemis signata signata was recorded regularly along Transect 1 and less frequently along Transect 6 and on a single occasion along Transect 2. Records of these species accounted for only 1.2% of all dragonflies and damselflies recorded during the surveys.

13.6.42 Whilst dragonflies and damselflies are common throughout the Assessment Area, analysis of the transect surveys indicate that the highest species richness is recorded in the southern part of the site, within the Buffer Zone, where there is greater diversity of habitats including wetland habitats.

13.6.43 Overall species diversity for this group is limited. Regular surveys carried out throughout the year revealed a fauna that is dominated by a few, common species. Butterflies

13.6.44 Fifty-eight species of butterfly were recorded within the Assessment Area, see Appendix 13-6. The majority of these are common and widespread although, nine species are considered to be uncommon, including Ampittia dioscorides, Eurema laeta, Graphium doson, Heliophorus epicles, Polyura athamas, Udaspes folus, Junonia orithya, Eurema brigitta and Hypolimnas misippus.

13.6.45 Of these species Eurema brigitta and Hypolimnas misippus are considered to be of local concern on the grounds that they are only known from 16 or less localities within Hong Kong (Fellowes et al. 2002). However no species recorded at the site are protected under Hong Kong SAR legislation nor are they considered to be Species of Conservation Importance according to the


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criteria stated in Annex 16 of the EPD's Technical Memorandum on Environmental Impact Assessment.

13.6.46 Analysis of the transect data indicates that whilst butterfly species were recorded throughout the site, species richness was greatest in the southern part of the Assessment Area, within the Buffer Zone where there is more diversity of both wet and dry habitats. Both species of local concern were recorded rarely with only 3 individuals of Eurema brigitta recorded along Transect 3 and a single individual of Hypolimnas misippus recorded along Transect 4.

13.6.47 The value of the Assessment Area for this fauna group is limited due to the limited range and extent of terrestrial habitats within the Assessment Area. The species present are largely common species that feed (in larval and adult stages) on the common and depauperate flora that typifies the disturbed habitats of much of the site. Species richness is greater in the southern part of the Assessment Area because of the presence of a greater range of habitats and hence food plants. Disturbance and unsympathetic management, however, still limit the value of these areas for terrestrial invertebrate fauna, including butterflies. Fish

13.6.48 During the course of this survey five species of freshwater fishes, including two native species and three alien species were recorded (see Appendix 13-7). The species recorded were Carassius auratus (Goldfish), Monopterus albus (Oriental swamp eel), Gambusia affinis (Mosquito fish), Oreochromis niloticus (Nile Tilapia) and Channa striata (Striped snakehead). In addition to the species found during this survey, Clarias gariepinus, the introduced African catfish is known from similar areas with disturbed habitats in the northern New Territories, and is likely to be found in the ditches and ponds of FLW. This is an alien species of no conservation value.

13.6.49 Carassius auratus is native to Hong Kong and uncommon. All individuals seen during the survey were dead specimens, probably discarded by fish farmers. Monopterus albus is a lowland species favouring slow-flowing streams and wet agricultural areas. Although still widespread, this species is on the decline due to the destruction of suitable habitat in rural areas of the New Territories (Chong and Dudgeon 1992). As all individuals seen were young, breeding is confirmed in the study area. Gambusia affinis is an alien species of no conservation value that it is widespread and common in Hong Kong. Individuals seen included young of the year, and breeding is thus confirmed in the study area. Oreochromis niloticus is an alien species of no conservation value. Individuals seen included shoals of young of the year, and breeding is thus confirmed in the study area. Channa striata is an alien species known to have recently established in Hong Kong (Cheung 1999). All specimens seen were fry or young fish indicating the species is breeding in this drainage system. It is widespread and common in the northern New Territories, especially the northwest. This species is a fierce invasive predator and is of no conservation value.

13.6.50 All waterways sampled were polluted and many were disturbed and/or choked with aquatic plants (such as the exotic and highly invasive Water Hyacinth (Eichhornia crassipes)), which clearly limits the diversity of lowland freshwater fish.

13.6.51 Most species found or expected to occur are alien species. No fish species of conservation value were found during the study period and although surveying in highly turbid waters limits fish detection, none are expected. Although Monopterus albus, a species thought to be in decline in Hong Kong (Chong and Dudgeon 1992), is of some interest it is not considered to be a Species of Conservation Importance. Amphibians

13.6.52 Eight species of frog were recorded during the surveys of the Assessment Area (see Appendix 13-8). With the exception of Two-Striped Grass Frog (Rana taipehensis), these are all common species that are widespread within Hong Kong. Two-Striped Grass Frog has a limited distribution in the New Territories and as it is known from 16 or less locations in Hong Kong it is considered to be of local conservation concern by Fellowes et al. (2002). However no amphibian species recorded at the site are protected under Hong Kong SAR legislation nor are they considered to be Species of Conservation Importance according the criteria stated in Annex 16 of the EPD's Technical Memorandum on Environmental Impact Assessment.

13.6.53 Although frogs were recorded throughout the site, Transect 1 in the southern part of the


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Assessment Area, within the Buffer Zone, yielded the most species richness and individual abundance. This transect was the only location where Two-Striped Grass Frog was recorded. Reptiles

13.6.54 Twelve species of reptiles were recorded during the surveys of the Assessment Area, including five species of lizards and seven species of snake (see Appendix 13-9). The lizard species recorded are all widespread within Hong Kong, however, all the snakes, with the exception of Checkered Keelback and White-spotted Slug Snake are considered to be of some conservation value (Table 13-27).

Table 13-27 Reptile Species of Some Conservation Value, Their Habitat Preferences and Observed Relative abundance within the Assessment Area at Fung Lok Wai

Species Conservation concern and distribution*

Recorded abundance

Habitat preference*

Banded Krait Bungarus fasciatus

Regional concern D

Rare Low lying areas near marshes, cultivated fields and shrub land

Common Rat Snake Ptyas mucosus

Potential regional concern China Red Data Book species N/A

Rare Varied including agricultural areas, shrub land and around ponds and reservoirs

Indo-Chinese Rat Snake Ptyas korros

Potential regional concern China Red Data Book species N/A

Rare Open habitats, including banks of streams and reservoirs, cultivated fields, ponds and shrub land

Many-banded Krait Bungarus multicinctus

Potential regional concern N/A

Rare Varied, including forest, agricultural areas and the edges of mangroves

Mangrove Water Snake Enhydris bennettii

Local concern C China Red Data Book species

Rare Muddy coastal habitats

Local Distribution: A = known in this locality alone; B = known to occur in two localities; C = known to occur in three to four localities; D = known to occur in five to eight localities; E = known to occur in nine to 16 localities; F = known to occur in 17 to 32 localities; N/A – no local rating. * Levels of conservation concern and habitat preferences based on Fellowes et al. (2002) and Karsen et al. (1998).

13.6.55 Although reptile species were recorded throughout the Assessment Area, they were not abundant. Most were recorded only on one occasion throughout the survey period.

13.6.56 Banded Krait is typically found in low-lying areas particularly near marshes, areas under cultivation and in shrub land. During the baseline surveys it was only recorded within the Transects 1 and 2 which are centred on agricultural habitats in the southern part of the assessment area. Common Rat Snake is found in a variety of habitats, including agricultural land and shrubs, particularly close to water. During the baseline surveys the only record of this species was from Transect 5 which is located to the west of the Tai River. Indo-Chinese Rat Snake is also typically found in Hong Kong in a variety of habitats, including banks of streams and reservoirs, cultivated fields, ponds and shrub land. During the baseline surveys it was only recorded from Transect 10 which is located in hill-side woodland and scrub mosaic habitats. Many-banded Krait is found in Hong Kong in varied habitats including forest, agricultural areas and the edges of mangroves. During the baseline surveys it was recorded in Transect 1 which is focused on agricultural land uses in the southern part of the assessment site and Transect 6 which runs adjacent to mangroves and fish ponds. Mangrove Water Snake is associated with muddy coastal habitats although in the baseline surveys it was only recorded from Transect 7 which is in the central fishpond area.

13.6.57 Although there was no consistent pattern in snake distribution, the key area was found to be the southern section of the Buffer Zone which is composed of a range of wetland, agricultural, grassy and woody habitats is, therefore, considered to be of moderate to high value for snake species,


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including Species of Conservation Importance. Birds Transect Surveys

13.6.58 A total of 142 species of bird were recorded during surveys of the Assessment Area. Of these 116 species were recorded within fishpond and associated wetland habitats and 68 species from the hillside transects in the south of the site (see Appendices 13-10 and 13-11). Aquaculture ponds 63, 77 to 87 were not surveyed on 17 September 2001 due to severe flooding at the site preventing access to these ponds.

13.6.59 All bird species are currently protected under the Wild Animals Protection Ordinance (Cap. 170). However, there are considerable differences between species in relation to their distribution, rarity, threat and overall conservation status.

13.6.60 Twenty-four bird species, considered to be Species of Conservation Importance based on a range of criteria, were regularly recorded in significant numbers at the site (see Table 13-28). Most are strongly associated with wetland habitats, including aquaculture ponds, permanent water courses, marsh, reed bed, wet agriculture intertidal habitats. Due to the limited distribution of these habitats in Hong Kong many of these species are largely restricted to the Deep Bay area. In addition, bird of prey species (which were recorded rarely foraging/flying over the site) were also included due to their large home ranges and their sensitivity to disturbance.


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Table 13-28 Bird Species of Conservation Importance Recorded in Significant Numbers within the Assessment Area of Fung Lok Wai

Common name Scientific name

Protection status

IUCN Redlist Status

Hong Kong Fauna of conservation concern

Habitat preference in Hong Kong

Global conservation concern

Black-faced Spoonbill Platalea minor C, HK EN PGC

Mudflat, drained Gei wais and aquaculture ponds

Greater Spotted Eagle Aquila clanga B1, B2, C, HK VU GC

Brackish and freshwater marsh areas and fishponds

Imperial Eagle Aquila heliaca B1, B2, C, HK VU GC Marshes, aquaculture ponds and adjacent hillsides in Deep Bay area. Also recorded in the NW, NE & central New Territories

Red-billed Starling Sturnus sericeus HK LC GC

Aquaculture ponds, wet agricultural areas, perimeter of reedbeds; and natural and artificial drainage channels.

Regional conservation concern

Black Kite Milvus migrans HK LC RC

Sea, coast, intertidal mudflat, aquaculture ponds, grassy and shrubby hillsides and harbours.

Common Teal Anas crecca B2, HK LC RC Shallow wetlands including aquaculture ponds

Eurasian Wigeon Anas penelope B2, HK LC RC Intertidal areas, marsh and fishponds

Osprey Pandion haliaetus B2, C, HK LC RC

Bays, coastal areas, gei wais, aquaculture ponds, reservoirs

Potential regional conservation concern

Chinese Pond Heron Ardeola bacchus HK LC PRC

Freshwater marsh, aquaculture ponds and bunds, wet agriculture, rivers and drainage channels.

Great Cormorant Phalacrocorax carbo HK LC PRC

Coastal areas, aquaculture ponds

Great Egret Egretta alba A, J, HK LC PRC Wetlands, particularly shallow intertidal bays, aquaculture ponds and marshes.

Grey Heron Ardea cinerea HK LC PRC

Abundant winter visito to Deep Bay associated with freshwater marsh, aquaculture ponds and bunds, wet agriculture, rivers and drainage channels.

Little Egret Egretta garzetta HK LC PRC

Wetlands including intertidal mudflats, gei wai, also aquaculture ponds, wet agriculture, marsh and banks of rivers and streams


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Common name Scientific name

Protection status

IUCN Redlist Status

Hong Kong Fauna of conservation concern

Habitat preference in Hong Kong

Local conservation concern

Black-crowned Night Heron

Nycticorax nycticorax HK LC

LC

Coastal and sub-coastal wetlands, including aquaculture ponds, marsh, mangrove, intertidal mudflats, riverine wetlands

Cattle Egret Bubulcus ibis A, HK LC LC Freshwater marsh, aquaculture pond bunds, wet agriculture.

Collared Crow Corvus torquatus HK

Primarily in Deep Bay, including rocky and sandy shores, intertidal mudflats, gei wai, aquaculture ponds

Crested Serpent Eagle

Spilornis cheela C, HK

LC LC Hillside, woodland, rocky hilltops, undisturbed small marshes, abandoned wet paddies

Little Grebe Tachybaptus ruficollis HK

LC LC Gei wai, aquaculture ponds particularly those with emergent and submerged vegetation

Little Ringed Plover Charadrius dubius

A, HK LC LC Low-lying land close to freshwater: wet agriculture, reclaimed land,

freshwater marsh, aquaculture ponds (particularly when drawn down) & coastal areas adjacent to freshwater streams

Pied Kingfisher Ceryle rudis HK

LC LC Fresh, brackish and saltwater wetlands including aquaculture ponds, gei wai, sheltered bays.

Striated Heron Butorides striatus HK

LC LC Mangroves and inter-tidal mudflats

Temminck's Stint Calidris temminckii

B2, HK LC LC Feeds and roosts in drawn down aquaculture ponds. Also forages in

freshwater marsh.

White-throated Kingfisher

Halcyon smyrnensis HK LC LC Golf courses, gardens, aquaculture ponds.

Wood Sandpiper Tringa glareola A, B2, HK

LC LC Low lying areas of freshwater marsh, wet agricultural land and aquaculture ponds in the New Territories particularly Long Valley. During spring passage observed on the intertidal mudflats.

Protection Status: B1 = listed on Appendix I of the Bonn Convention; B2 = listed on Appendix II of the Bonn Convention; A = listed under an agreement between the Government of Australia and the Government of the People’s Republic of China for the Protection of Migratory Birds and their Environment; J = listed under an agreement on the Protection of Migratory Birds and their Habitats between the Government of Japan and the Government of the People’s Republic of China; C = protected in the People’s Republic of China; HK = protected in the Hong Kong SAR; IUCN Red List: Source: www.iucnredlist.org EN = Endangered; VU = Vulnerable; LC = Least Concern Hong Kong Fauna of conservation concern: Source: Fellowes et al. (2002) GC = Global Concern; RC = Regional Concern; PGC = Potential Global Concern; PRC = Potential Regional Concern; LC = Local Concern.


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13.6.61 Four species were recorded that are considered to be of global conservation importance and these are described in more detail in the paragraphs below.

13.6.62 Black-faced Spoonbill - Breeds on the west coast of the Korean peninsula and in Liaoning, northeast China. Over winters in northern Vietnam, southern and eastern China including Deep Bay, Taiwan and Japan. It is a winter visitor to Hong Kong and possibly a passage migrant. Highest counts occur during autumn commencing in the third week of October. The species typically departs Hong Kong during the second week of April, although small numbers have been recorded in Deep Bay during the summer since 1984. BirdLife International estimates the world population of this species to be 1,480 individuals. The over-wintering population has increased since 1987-88 when peak winter counts were low (about 35 individuals) to a peak of 346 individuals in January 2006 (Anon 2006). Deep Bay is a critically important to the survival of this species and, during winter, has regularly supported about 20-25% of the world population. During these surveys Black-faced Spoonbill was recorded within actively managed aquaculture ponds, particularly when ponds were drawn-down.

13.6.63 Greater Spotted Eagle – This species is a scarce and local winter visitor to the northern New Territories primarily between the end of October and end of March. The winter population appears to have declined probably due to at least in part to the disappearance of domestic duck-farming in Deep Bay area. This species was observed very rarely during baseline surveys only once (during February) overflying the assessment area from the hillside survey transect (Transect 6). The scarcity of this species is reflected in the counts for both the Deep Bay area (where a maximum of 4 individuals were recorded in winter 2004/05) and the DBF recording area where there were no records reported during monitoring surveys undertaken by the HKBWS (see Appendix 13-12). Greater Spotted Eagle will forage for prey over aquaculture ponds and brackish and freshwater marshes so the wetland habitats at Fung Lok Wai could comprise potential habitat, although the rarity of observations in this area imply that the Hong Kong population of this species has very little reliance upon it.

13.6.64 Imperial Eagle – This species is a common winter visitor, possibly a passage migrant through Hong Kong in February. Mainly observed during November to March, with numbers peaking in mid-winter. The distribution of this species is closely associated with the distribution of ducks, although is not often seen over intertidal areas. During these surveys Imperial Eagle was observed rarely over-flying the assessment area foraging for prey. This species was observed rarely (although more frequently than Greater Spotted Eagle) during baseline surveys with a maximum count of 2 individuals overflying the assessment area seen in January. The scarcity of this species is reflected in the counts for both the Deep Bay area (where a maximum of 5 individuals were recorded in winter 2003/04 and 2004/05) and the DBF recording area where a maximum of 1 individual was recorded in winter 2004/05 (see Appendix 13-12). Imperial Eagle will forage for prey over aquaculture ponds, marshes and adjacent hillsides in Deep Bay area so the wetland habitats at Fung Lok Wai could comprise potential habitat, although the rarity of observations in this area imply that the Hong Kong population of this species has very little reliance upon it.

13.6.65 Red-billed Starling - Breeds only in China, however, it is a winter visitor in northern Indochina and an abundant but localised winter visitor to Hong Kong, where it forms large flocks that are considered to be of international significance. Recorded from the third week in October, numbers peak during the first two weeks of November. Typically departs Hong Kong during the second half of March. It tends to occur in large flocks and is primarily recorded in Deep Bay, as well as Long Valley, Kam Tin, Starling Inlet and Shuen Wan. The protection of roost sites in inter-tidal forest habitats and the intensification of aquaculture in the Deep Bay area (which may have created increased feeding opportunities) possibly accounts for the significant increase in the over-wintering population since the 1980s. During these surveys Red-billed Starling was frequently recorded around aquaculture ponds and adjacent to permanent watercourses during winter.

13.6.66 Of the 24 bird species of conservation importance recorded within the Assessment Area, 20 species were recorded within the Study Site (see Table 13-29). Four additional species were recorded from the 500m buffer zone surveyed. No bird species of conservation importance were recorded solely from the Proposed Development Area. However, 11 species were recorded using the habitats within the Proposed Development Area but all of these species were recorded in significant numbers elsewhere on the site. The figures suggest that the aquaculture ponds of the


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Proposed Development Area are similar to those found elsewhere within the Study Site, they are of similar character and support a similar range of species.

Table 13-29 List of Bird Species of Conservation Importance Recorded in Each Section of the Assessment Area at Fung Lok Wai.

Common name Scientific name Proposed Development Area

Study Site Buffer Zone

Global conservation concern Black-faced Spoonbill Platalea minor * * Greater Spotted Eagle Aquila clanga * Imperial Eagle Aquila heliaca * * Red-billed Starling Sturnus sericeus * * * Regional conservation concern Common Teal Anas crecca * * Eurasian Wigeon Anas penelope * *

Osprey Pandion haliaetus *

Potential regional conservation concern Black Kite Milvus migrans * * * Chinese Pond Heron Ardeola bacchus * * *

Great Cormorant Phalacrocorax carbo * * *

Great Egret Egretta alba * * * Grey Heron Arda cinerea * * Little Egret Egretta garzetta * * * Local conservation concern Black-crowned Night Heron

Nycticorax nycticorax * *

Cattle Egret Bubulcus ibis * * * Collared Crow Corvus torquatus * * Crested Serpent Eagle Spilornis cheela *

Little Grebe Tachybaptus ruficollis * * *

Little Ringed Plover Charadrius dubius * *

Pied Kingfisher Ceryle rudis * * *

Striated Heron Butorides striatus * *

Temminck's Stint Calidris temminckii *


Halcyon smyrnensis * * *

Wood Sandpiper Tringa glareola * * * * Indicates presence

Flightline surveys

13.6.67 To understand patterns of bird movement within the site the flight line data collected during bird flight line surveys were collated and aggregated.

13.6.68 During the survey period 4052 individual birds were observed flying over some sector of the Study Site (Figure 13-10). These flightline data recorded are summarised by bird group and altitude category in Table 13-30.


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Table 13-30 Abundance and Proportion of Birds Observed Within the Study Site by Altitude Category (February-December 2001)

Height

Group <20m 20-40m 40-60m >60m All No. % No % No. % No. % No. %Ardeid 1,391 94.5 1,010 76.6 134 12.8 40 18.8 2,575 64

Waterbird 46 3.1 263 19.9 843 80.4 52 24.4 1,204 30

Raptor 35 2.4 46 3.5 71 6.8 121 56.8 273 6

Total 1,472 1,319 1,048 213 4,052 100

13.6.69 Ardeids (2575, 64%) are clearly the most abundant group overall (Table 13-30) and comprise, with other waterbirds (1204, 30%), 94% of all individuals recorded. As would be expected raptors, overall account for a small proportion of individuals observed (273, 6%). At lower altitudes ardeids are clearly dominant, with Little Egret the most abundant species recorded below 40m (Table 13-31). Above 60m Black Kite accounts for the majority of records. Great Cormorant are abundant upwards of 20m and dominant in the 40-60m altitude category.

Table 13-31 Dominant Species by Altitude Category

Altitude category Dominant species (number recorded) <20m Little Egret (848), Great Egret (291), Chinese Pond Heron (137)

20-40m Little Egret (743), Great Cormorant (245) 40-60m Great Cormorant (740) 60m+ Black Kite (113), Great Cormorant (52)

13.6.70 These data reflect the observed behaviour of birds, with herons and egrets moving between ponds, often in short hops at relatively low altitudes, as they forage. Raptors, such as Black Kites, however, tend to forage at higher altitude, circling over ponds in search of food.

13.6.71 A total of 529 birds, 13% of all records for the site (4052), were observed flying through the sector of the Assessment Area occupied by the Proposed Development Area. Whilst, initially, this proportion seems high (the Proposed Development Area is only 5% of the area of the Study Site) it must be recognised that the records for this sector are not exclusive. That is, as birds fly through the site they intersect with many different sectors. On the basis of the distribution of flightlines revealed by the surveys, it is expected that any equivalent 4 ha sector located any where within the site would intersect with a similar proportion of flightlines.

13.6.72 Data for all individuals at each altitude category (Table 13-32) indicates, however, that a disproportionately large number of birds are flying below 40m within the entire site (68.8%) and that for the proposed development sector this proportion is even higher (93.9%).

Table 13-32 Comparison of Total Individuals for Each Altitude Category within the Study Site and the Proposed Development Area

Altitude category

Total individuals for Study Site

Total individuals for Proposed Development Area

<20m 1,472 (36.3%) 255 (48.3%) 20-40m 1,320 (32.5%) 241 (45.6%) 40-60m 1,048 (25.9%) 15 (2.8%) >60m 2,13 (5.3%) 17 (3.2%)

Total 4,052 528


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Species composition

13.6.73 Analysis of the species composition of those flights occurring within the sector of the site occupied by the proposed development (Table 13-33 and Table 13-34 reveals a broadly similar pattern to those for the entire site with the following exceptions: • A higher proportion of ardeid species 92.4% (488 individuals) were observed within the

footprint of the proposed development compared to the Study Site as a whole where ardeids comprised 64% of all individuals observed.

• A much lower proportion of waterbird species 1.5% (8 individuals) were observed within the Proposed Development Area compared to the Study Site as a whole where waterbirds comprised 23% of all individuals observed.

Table 13-33 Abundance and Proportion of Birds Observed within the Proposed Development Area by Altitude Category (February-December 2001)

Height Totals

Group <20m 20-40m 40-60m >60m

No. % No. % No. % No. % Total %

Ardeid 250 98.0 228 94.6 9 60.0 1 5.9 488 92.4

Waterbird 3 1.2 2 0.8 2 13.3 1 5.9 8 1.5

Raptor 2 0.8 11 4.6 4 26.7 15 88.2 32 6.1

Total 255 241 15 17 528 100

13.6.74 The most abundant species observed within the Proposed Development Area were Little Egret and Chinese Pond Heron (Table 13-34), although the abundance of these species is expected to have declined following the abandonment of the egretry (see below). The vast majority of flightline activity for both Little Egret and Chinese Pond Heron observed within the area of the proposed development were below 40m and occurred during the breeding season, April to July.

Table 13-34 Dominant Species Recorded at Each Altitude Category within the Proposed Development Area

Altitude category Dominant species <20m Little Egret (191), Chinese Pond Heron (51) 20-40m Little Egret (182), Chinese Pond Heron (35) 40-60m Cattle Egret (5), Black Kite (4), Little Egret (4) >60m Black Kite (14)

Egretry

13.6.75 The relatively high proportion of Little Egret and Chinese Pond Heron individuals recorded within the Proposed Development Area can be largely explained by the establishment of an egretry on the south-west perimeter of the Assessment Area during March 2001, the Shing Uk Tsuen egretry. The flightlines of birds to and from this egretry tend to track across the south west corner of the study site, particularly at lower altitudes (<40m) (Figure 13.11). More recently it appears that this egretry has now been abandoned (see Anon 2005). It is anticipated that the continued abandonment of this egretry will have two consequences for the analyses presented above: • The overall levels of flight activity for ardeids will be less than that shown above. • There will be substantially fewer flightlines within the Proposed Development Area, there

being less reason for birds to move between Fung Lok Wai and the South-western part of the Assessment Area.


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13.6.76 Another egretry has recently been found at Ha Mei San Tsuen. This egretry is outside the Assessment Area and is located so far away that the development would unlikely to have material impact on the flight lines of this egretry. As far as foraging areas are concerned, it is unlikely that birds from this egretry utilise ponds in the development footprint more than was the case in Shing Uk Tsuen egretry. Mammals

13.6.77 The mammal fauna of Hong Kong is poorly known compared to other fauna groups and there is limited information about the occurrence of mammal species in the Fung Lok Wai area. Opportunistic sightings of tracks, marks and scats indicate, however, that at least two species are likely to utilise the Assessment Area: Seven-banded Civet (Vivericcula indica) and Small Asian Mongoose (Herpestes javanicus). Neither of these species is threatened or restricted in area and are not considered species of conservation importance.

13.6.78 There are a number of mammal Species of Conservation Importance that were not recorded during the twelve months of survey but are known to occur within similar habitats in the Deep Bay area. These include: Eurasian Otter (Lutra lutra) and Crab-eating Mongoose (Herpestes urva). The large numbers of flying insects associated with fishponds and agricultural land are also likely to support bat populations, including, potentially, Noctule Bat (Nyctalus noctula), Leschenault's Fruit Bat (Rousettus leshenaulti) Lesser Yellow-house Bat (Scotophilis kuhlii), though no bat roosts were observed during the survey period. Conclusions

13.6.79 The Fung Lok Wai Assessment Area supports a number of Species of Conservation Importance. In particular, it is of significance for bird species.

13.6.80 Two species of Global Conservation Concern, Black-faced Spoonbill and Red-billed Starling, are directly reliant on the wetland areas of the Assessment Area. Two eagle species of Global Conservation Concern have been recorded over the Assessment Area and are known to predate upon wetland bird species (such as ducks) that are themselves dependent upon the site. There are 20 other bird species of Regional or Local Conservation Concern. With the exception of Crested Serpent Eagle these are all waterbirds or raptors with a close association with the Aquaculture Ponds habitat.

13.6.81 Other than birds the only other Species of Conservation Importance identified during the baseline surveys are 5 species of reptile: Banded Krait, Common Rat Snake, Indo-Chinese Rat Snake, Many-banded Krait and Mangrove Water Snake.

13.6.82 In addition there are other species of amphibian, reptile, mammal, invertebrates and plant that are considered to be of some conservation value. For these species the wetland habitats of the southern part of the Assessment Area, within the 500m Buffer Zone, including wet agriculture and freshwater marsh are particularly important.

13.6.83 Surveys were completed in January 2002 when most aquaculture ponds were under active management. Since completion of the surveys there has been no change in wetland area, there has been no in-filling of fish ponds, for example. There has, however, been a change in management of fish ponds. Site visits undertaken in recent years, including by WWF staff, indicate that relatively few ponds (about one quarter) are now in active production (Janet Lee, Pers. Comm.). For abandoned ponds, grass has encroached into the open water from the side of the ponds and Water Hyacinth (Eichhornia crassipes) is abundant in some these. In the absence of active management, bunds have become covered by long grass which reduces their attractiveness as roosting sites for waterbirds.

13.6.84 As the extent of wetland has not changed it is considered that the importance of the site for most species, including birds that are not dependent on the active fishpond management (eg Red-billed Starling) and non-avian fauna (such as reptiles) will be unchanged. For those birds that are dependent on the active management of fish ponds (including egrets and Black-faced Spoonbill) it is expected that the importance of the site will have declined.

13.6.85 Since the completion of the surveys the egretry at Shing Uk Tsuen has now been abandoned (Anon 2005) and this is expected to reduce the activity of herons and egrets within Fung Lok Wai.


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13.6.86 It is considered that the results of these surveys remain applicable to the assessment. Any changes taking in place in the intervening period are expected to involve a reduction in ecological value due to a reduction in management activity. This is likely to effect bird species most as these tend to benefit from aquaculture activities that periodically provide access to food resources.

13.7 Identification of Potential Impacts

Summary of proposed development 13.7.1 The proposed development involves the conversion of approximately 4ha of aquaculture pond,

located on the southern boundary of the Fung Lok Wai study site, to residential development. The proposal involves the construction of residential apartments, landscaping, car-parking and other ancillary structures.

13.7.2 The proposed vehicular access of the site, viz. the Southern Development Access, will be via the existing Fuk Shun Street and Yuen Long Industrial Estate to Yuen Long.

13.7.3 The construction and operation of the residential development will result in direct habitat loss and short and long-term disturbance to species of conservation importance (see below) as a consequence mitigation is proposed in the form of a Wetland Nature Reserve (WNR). This WNR will be constructed on the remaining, approximately 76.1 ha of the study site unaffected directly by the residential development. The WNR will comprise a large expanse of enhanced fishponds and re-recreated marshland habitat.

13.7.4 To minimise the impact of the residential construction on sensitive species it has been decided that the WNR will be constructed in advance of the residential development. This sequence of development has the advantage of minimising the negative effects (particularly disturbance) of residential construction, however, it also means that the effects of the mitigation works themselves, including temporary habitat loss and disturbance, on Species of Conservation Importance must also be considered in the impact assessment.

13.7.5 The construction of the WNR is divided into Sectors as described in Section 13.9. At each stage the maximum area of pond unavailable due to construction works is shown along with the remaining area unaffected by construction works. Potential impacts

13.7.6 Initial analysis of baseline data indicated three constraints on the proposed development: • The location of the egretry in the southern part of the assessment area could result in flight

line interference of birds attempting to access food resources within Fung Lok Wai. The preferred option, therefore, is to construct the residential development at a location approximately 150m eastwards of the original proposed location. This location remains the preferred option even though the egretry is now abandoned;

• Accessing the site from the west adjacent to the Hong Kong Wetland Park, as originally proposed, will require additional construction work and, potentially, disturbance to the egretry. The preferred option, therefore, is to provide access to the residential development from the south through existing roads; and,

• It is desirable to conserve existing wetland habitat and maintain linkages between all the wetland habitats within the Fung Lok Wai assessment area, including the mosaic of wetlands in the southern part of the Assessment Area. The WNR design has, therefore, been modified to accommodate the relocated development area. The preferred design for the WNR maintains connectivity with adjacent wetlands including those in the southern part of the assessment area.

13.7.7 Section 3 describes, in more detail, the development of the preferred options. Options 1A and 1B are considered to be broadly similar in ecological terms. They occupy the same area, hence habitat loss will be the same in each option nor is there considered to be a significant difference between the two options in terms of disturbance, pollution, soil compaction or hydrological disruption. The only slight difference between the options is potential with respect to fragmentation and this is considered in more detail below.


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13.7.8 The following potential impacts arising from the construction and operation of these preferred development options are considered in more detail below: • Habitat loss; • Habitat fragmentation; • Disturbance; • Pollution; • Soil compaction; and, • Hydrological disruption. Habitat loss

13.7.9 There will be no permanent habitat loss to ecologically valuable habitats in the WCA or WBA. The actual operation phase footprint (i.e. land directly and permanently lost by the project) will be approximately 4.0 hectares (primarily Aquaculture Ponds with a very small area of drainage channel). This change in habitat use will occur within the WCA as a result of the land used for the construction of residential blocks, associated structures and access roads and storage areas for materials and equipment etc. However the loss of water body is compensated by re-profiling the ponds in the WNR area. This creates ecologically enhanced and enlarged ponds, and recreated marshland habitat. The construction and ongoing management of these habitats (as outlined in the HCMP) is anticipated to fully compensate any potential loss of wetland ecological function arising from the effects of the residential development. In particular management will be focused on maintaining the population levels of key Species of Conservation Importance, including waterbirds. Consequently under the proposal there is no net loss of water body area or ecological function. No additional habitat loss is anticipated as a result of the construction of either sewerage strategy or the preferred (southern) access route.

13.7.10 No habitats will be lost in their entirety or in any significant proportion.

13.7.11 An integral component of the proposal is the development of a Wetland Nature Reserve (WNR) on the remaining 76.1 hectares of the site. The creation of the WNR will involve the transformation of approximately 14.4 hectares of aquaculture ponds to freshwater marsh and the enhancement (through enlargement) of 61.7 hectares of aquaculture ponds. Whilst intended to compensate for impacts arising from the construction of the residential component of the development and, therefore, expected to have overall positive benefit, the WNR works will involve permanent and temporary habitat loss of aquaculture ponds (fishponds that are actively managed, those that are currently unmanaged, and the intervening bunds) and ditches and drainage channels. Habitat Fragmentation

13.7.12 Construction of the proposed development along the southern edge of the study site is not likely to result in significant fragmentation of habitat areas either within the study site or from other wetland areas in the WCA, the WBA and Ramsar site or other identified sensitive ecological receivers. Construction may create a temporary barrier to dispersal particularly for small vertebrate species such as amphibians and small mammals utilising the mosaic of habitats in the southwest. This area consists of a mosaic of small ponds, drainage channels, wet agriculture and reedbed. No additional habitat fragmentation is anticipated as a result of the construction of either sewerage strategy or the preferred (southern) access route.

13.7.13 The egretry at Shing Uk Tsuen was located to the south west of the Proposed Development Area within an area of Fung-shui woodland. Construction of the development at this originally proposed location would have directly obstructed flightlines and reduced sightlines between the egretry and fishpond foraging areas. The preferred development options (1A and 1B) have been relocated to reduce this effect. The dramatic reduction in flightline obstruction achieved through this relocation is illustrated in Table 13-35. Several conservative assumptions made in this analysis probably, however, result in an over-estimate of flightline obstruction including: • All flightlines intersecting with the footprint of the proposed Development Area will be

completely obstructed. In practice it is anticipated that open space within the development will provide opportunities for passage, although this effect is expected to be small; and,


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• Birds will not modify their flightlines to pass around the development to forage in the ponds beyond. In practice it is expected that birds may take a more circuitous route to access food resources. The magnitude of this effect is not known.

Table 13-35 Comparison of Potential Affect on Egretry Flightlines of Alternative Development Scenarios

Original location

Preferred option (Relocated 150m eastwards)

Number (percentage) of flightlines from egretry intersecting with Proposed Development Area 330 (65%) 120 (24%)

13.7.14 The abandonment of the egretry (see Anon 2005) is expected to significantly reduce the number

of flightlines passing through the proposed development area, there being less reason for birds to move between Fung Lok Wai and the South-western part of the Assessment Area. There is no indication that the flightlines of other species are likely to be significantly affected by the construction or operation of the residential development as the numbers of other (non-ardeid) species observed during flightline surveys was relatively very low (see Tables 13-33 and 13-34), this includes Great Spotted Eagle, Imperial Eagle, Crested Serpent Eagle and Osprey.

13.7.15 Options 1A and 1B are similar in many respects, the only slight difference between these two options arising from the larger number of buildings in Option 1B. The buildings in Option 1A will be slightly higher (14-18 stories) than those proposed in Option 1B (all 15 stories). It is considered that the effects of reducing the spacing of buildings will reduce sightlines to a greater extent than the slight differences in building height proposed. On this basis it is concluded that Option 1B will have a slightly greater impact, with respect to this effect, than Option 1A.. It is emphasised that the difference between these options is slight, particularly in light of the abandonment of the egretry, as it was the potential blockage of flights to and from this feature that was the principal source of concern with respect to habitat fragmentation, and neither are expected to cause significant barrier effects to ardeids or any other species, including raptors. Disturbance

13.7.16 General disturbance effects are widely recognized and have been documented in the past (e.g. Hockin et al. 1992). Such effects may include the complete avoidance of an area (which is therefore comparable to habitat loss) and reduced densities (e.g. where only certain less-sensitive or accustomed individuals use the area). Other less-obvious disturbance effects may include reduced habitat quality through reduced feeding efficiency (e.g. because of a need for increased vigilance), which may in turn lower survival rates or breeding output. Care must therefore be taken in interpreting the observation of a species close to a disturbance source as being evidence that there is no disturbance effect. On the other hand, the observation that there is a disturbance effect, may not necessarily mean that this results in a population impact, as animals may, for example, move to alternative areas if suitable habitat is in excess (i.e. populations are not at carrying capacity).

13.7.17 According to Hill et al. (1997) the severity and overall impact of disturbance (at least on birds) is likely to depend on the following factors: • Intensity of disturbance; • Duration and frequency of disturbance (continuous, infrequent, regular, variable); • Proximity of source; • Seasonal variation in sensitivity of affected species; • Presence of people associated with the source; • Whether animals move away, but return after disturbance ceases; • Whether important numbers are affected; • Whether there are alternative habitats available nearby;


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• Whether rare, scarce or especially shy species are affected.

13.7.18 In particular, disturbance impacts are normally greatest when they are close and frequent. Although, some species can adapt to regular disturbances from noise and moving machinery, the close proximity of people is rarely adapted to. Thus, species tend to show increasing responses across a gradient of severity, from passive-low-level and continuous to active-high-level continuous (Hockin et al. 1992).

13.7.19 Although the long-term aim of the design of the WNR is to enhance the area for wildlife, the construction of the development and the proposed enhancement works will cause both permanent and temporary disturbance impacts to Species of Conservation Importance utilising the assessment area. Potential disturbance impacts will include: • Permanent disturbance from normal residential activities such as noise and visual disturbance

from people, vehicles and pets. • Permanent disturbance from fishpond management activities, however this level of

disturbance activity will be lower than currently exists on site, due to a reduction in fishpond operation recommended under the proposed management strategy, though this may be offset by an increase in visitors to the reserve.

• Permanent disruption of a proportion of flightlines to and from the egretry (now abandoned) due to the location of the residential units and access road.

• Disruption of flightlines and temporary noise and visual disturbance to birds during construction of residential units.

• Temporary direct disturbance to individual ponds during the improvement of fishponds within the WCA.

• Temporary noise and visual disturbance to the fishpond area from site traffic during construction of the development and Wetland Nature Reserve.

13.7.20 Noise level measurements carried out as part of this assessment indicate that predicted unmitigated noise levels during construction of the residential area may exceed noise limits for daytime construction activities as set out in Annex 5 of the EIAO-TM. Predicted noise levels can be brought within the noise limits through appropriate mitigation. However, it is predicted that some noise levels may reach 71-75dB at noise sensitive receivers on the south west boundary (see Section 4). These levels, although within acceptable noise limits, are likely to have some impact on sensitive species.

13.7.21 No additional disturbance is anticipated as a result of the construction or operation of sewerage strategy “A” which will follow existing roads. Sewerage strategy “B” will require some additional construction works to the west of the proposed development area and WNR, however, these works are not expected to create significant additional disturbance because they are: limited in extent; confined to areas that are already disturbed; and, of relatively short duration compared to construction work on the main development.

13.7.22 Construction and operation of the preferred (southern) access route is not expected to cause significant additional disturbance as it will follow existing roads and is remote from the fishpond areas that are considered to be most sensitive to disturbance effects. Pollution

13.7.23 Fugitive dust emissions from construction activities could result in significant ecological impacts primarily through deposited on nearby vegetation. This can cause vegetation damage, which can have secondary impacts on associated fauna (such as insects and birds).

13.7.24 Dust and exposed earth from construction operations may also enter watercourses through run-off, particularly during heavy rainfall periods. This can lead to high turbidity from soil particles and eutrophication as a result of nutrient enrichment (as phosphates, which are normally the limiting nutrient in freshwater systems, are bound to soil particles). Aquatic macrophytes may be reduced or lost completely as a result of reduced light penetration due to the increased turbidity from soil particles and increased free-floating algae populations following eutrophication. Severe eutrophication can also lead to oxygen depletion and the impoverishment of aquatic animal communities and, in turn, other animals, such as waterbirds, that feed on them. However, as


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reported under the water quality impact assessment chapter, the water quality in existing watercourses is poor and their ecological quality is low. Ecological degradation of these habitats may not, therefore, occur if pollutant levels in site run-off are not significantly above those of the watercourses, or if the run-off volume is relatively low. Additional sediment inputs, and potential associated additional nutrients loads may, however, have off-site impacts on the Deep Bay mudflats and coastal waters. Mitigation measures must be put in place to prevent adverse impacts on the ecological resources of Deep Bay.

13.7.25 Mitigation measures are designed to strive towards minimal pollution of watercourses from the construction and ongoing operation of the residential development and Wetland Nature Reserve are dealt with in more detail in the water quality chapter of this report.

13.7.26 Spills and run-off from construction sites can sometimes contain high levels of toxic pollutants (such as oil) which can cause direct mortality of plants and animals (in severe cases), sub-lethal impacts (e.g. by reduced breeding success) or indirect effects through impacts on food resources etc. Contamination of watercourses may have off-site effects on ditches, rivers and the valuable estuarine waters and mudflats of Deep Bay.

13.7.27 Bioaccumulation may also occur where toxic substances are passed up the food chain in increasing concentrations. As a result top level predators such as some reptiles, mammals and birds of prey can be particularly susceptible. Again, measures which should be put in place to prevent this impact are described in the water quality chapter of this report.

13.7.28 Mitigation measures, including the provision of twin pipelines will ensure that the impacts of emergency discharge from sewer bursting are controllable and that the need to shut down the pump house or to discharge untreated sewage into natural streams or channels is minimised. Soil Compaction

13.7.29 During construction, areas of land will be cleared for use as works areas. In addition, during fishpond enhancement work heavy machinery will be required to access areas of the site by tracking along bund ridges of the aquaculture ponds. During this period, some areas of ground, which are currently undisturbed, will be compacted for use as storage areas, vehicle movement or other purposes. Wetland areas into which rain quickly infiltrates, will become hardened and rainfall will wash off, taking sediment with it, to be deposited on land adjacent to the compacted site, or in watercourses. The wetland function of these areas may therefore be lost temporarily. Although the impact is temporary, extensive compaction over a long period will make habitat restoration more difficult because of the need to re-establish the soil base for a wetland area. Hydrological Disruption

13.7.30 The change in function of 14.4 hectares of aquaculture ponds to freshwater marsh will result in the necessary diversion of a small catchment runoff southwest of the study site to the southeast. The altered route of the catchment runoff should have no negative impact on the hydrology of the site.

13.7.31 Stormwater run-off from the development area will be directed into the fresh water marsh storage through appropriate silt and oil filters and is not expected to adversely affect water quality within this habitat. Summary

13.7.32 Various types of habitats (those considered to be of moderate value and above) affected by the potential impacts of the proposed development identified above are summarised in Table 13-36The significance of these potential impacts are assessed individually in Section 13.8.

13.7.33 The potential impacts under Options 1A and 1B on habitats are similar, although, as indicated above the effects of habitat fragmentation are expected to be slightly greater under Option 1B than 1A.


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Table 13-36 Summary Matrix of Potential Impacts on Various Types of Habitats

Habitat Habitat loss

Habitat fragmen

tation

Disturbance Pollution Soil compaction

Hydrological disruption

Intertidal forested wetlands X X

Permanent rivers, streams and creeks

Ditches and drainage channels

X X

Aquaculture pond X X X X

Reedbed X X X Permanent freshwater marsh and pools

X X X

Seasonally flooded (wet) agricultural land

X X X

Dry agricultural land X X

Inactive agricultural land X X

Orchard Fung-shui woodland (X)* X X

Semi-natural secondary woodland

X X

Plantation woodland

Grassland Grassland – shrubland mosaic

Landscaped area Works in progress

Wasteland Developed area

Note: * only if egretry present

13.8 Evaluation of impacts

13.8.1 Options 1A and 1B are considered to be broadly similar in ecological terms. They occupy the same area, hence habitat loss will be the same in each option nor is there considered to be a significant difference between the two options in terms of their potential impacts on sites of conseration importance or the effects of disturbance, pollution, soil compaction or hydrological disruption on habitats. The only slight difference between the options is potential with respect to habitat fragmentation, particularly with respect to the obstruction of the flightlines of birds, and this is considered in more detail below. Impacts on Site of Conservation Importance

13.8.2 In Section 13.4 the following sites of conservation importance were identified within the north-west New Territories: • Inner Deep Bay SSSI • Mai Po Inner Deep Bay Ramsar Site • Tsim Bei Tsui SSSI and egretry


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• Mai Po Nature Reserve and Mai Po Marshes SSSI

13.8.3 In addition the Study Site is located within the Deep Bay WCA. The Assessment Area is also adjacent to the Hong Kong Wetland Park.

13.8.4 Fung Lok Wai is sufficiently distant from the four key sites of conservation importance in the region that the risk of adverse effects arising from either the construction or operation of the Residential Development is considered to be very low. Disturbance effects caused during construction and operation are not, for example, expected to cause impact even to the most sensitive species beyond 500m from the Proposed Development Area. In Section 12 it was also concluded that there was a very low likelihood of impacts to marine habitats and hence marine components of the Mai Po Inner Deep Bay Ramsar Site and the Inner Deep Bay SSSI.

13.8.5 There will be no permanent habitat loss to ecologically valuable habitats in the WCA or WBA. The actual operation phase footprint (i.e. land directly and permanently lost by the project) will be approximately 4.0 hectares (primarily Aquaculture Ponds with a very small area of drainage channel). This change in habitat use will occur within the WCA as a result of the land used for the construction of residential blocks, associated structures and access roads and storage areas for materials and equipment etc. However the loss of water body is compensated by re-profiling the ponds in the WNR area. This creates ecologically enhanced and enlarged ponds, and recreated marshland habitat. The construction and ongoing management of these habitats (as outlined in the HCMP) is anticipated to fully compensate any potential loss of wetland ecological function arising from the effects of the residential development. In particular management will be focused on maintaining the population levels of key Species of Conservation Importance, including waterbirds. Consequently under the proposal there is no net loss of water body area or ecological function. No additional habitat loss is anticipated as a result of the construction of either sewerage strategy or the preferred (southern) access route.

13.8.6 The construction of the WNR adjacent to the Hong Kong Wetland Park is considered to be a positive feature as these two sites will collectively increase the availability of wetland habitat managed explicitly for conservation purposes in this part of the north-west New Territories.

13.8.7 Overall the proposed development is expected not to have an impact on sites of conservation importance. Habitat Impacts

13.8.8 The project will transform approximately 80.1 hectares of fishponds into a Residential Development and a Wetland Nature Reserve with, overall, a greater variety of wetland habitats and associated flora and fauna than that which currently exists. The WNR will be actively managed in the short and long term, for the benefit of Species of Conservation Importance identified utilising the site as well as other species associated with the Deep Bay environment.

13.8.9 The improvement of these habitats will inevitably result is some short-term disturbance while habitats are modified, restored and created. The impacts on habitats identified in the previous section that will be partially lost/changed or fragmented during this process, and those habitats that support Species of Conservation Importance that may be lost, changed or fragmented, are assessed in Table 13-37 to Table 54. In addition, all other habitats of moderate or high value have been assessed according to the criteria outlined in Annex 8 of the EIAO – TM. Habitat Loss

13.8.10 Construction and operation of the proposed development will result in temporary loss of habitats in the WCA due to the operational phase footprint. This will impact aquaculture ponds (a habitat that incorporates fishponds that are actively managed, those that are currently unmanaged, and the intervening bunds) and a small area of Ditches and Drainage Channels. However there is no net loss of water body due to pond re-profiling and enhancement works. The impacts to these habitats are assessed below.

Table 13-37 Summary of Impacts to Aquaculture Ponds from Habitat Loss

Criteria Remarks Habitat Quality High


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Species Numerous Species of Conservation Importance (particularly waterbirds) are associated with fishponds

Size/abundance Approximately 4.0 hectares lost to the development. Within the proposed WNR approximately 14.4 hectares will be permanently converted to freshwater marsh and approximately 61.7 hectares subject to pond enhancement resulting in temporary loss during the construction phase

Duration Aquaculture ponds within development area will be permanently lost. Those ponds converted to freshwater marsh will be permanently lost (considered to be of higher ecological value) and those subject to enhancement works will be temporarily lost during the construction phase, however there is no net loss of water body due re-profiling of ponds creating enlarged ponds (of higher ecological value)

Reversibility Impact is irreversible for those ponds lost to development and converted to freshwater marsh. Impact is reversible for those ponds subject to enhancement works

Magnitude High

Table 13-38 Summary of Impacts to Ditches and Drainage Channel from Habitat Loss

Criteria Remarks Habitat Quality Low Species The drainage channels on site are of low water quality and support no Species

of Conservation Importance Size/abundance There are approximately 0.4 hectares of ditches and drainage channels within

the WNR, of these approximately 0.02 hectares will be lost. Other sections will be modified to facilitate drainage within the WNR

Duration Permanent loss of approximately 0.02 hectares, temporary disturbance to remaining sections during WNR construction phase

Reversibility Impact is irreversible Magnitude Low.

Habitat Fragmentation

13.8.11 Some habitats located in the south-western part of the assessment area form a mosaic of wetlands that are of value to some fauna groups including invertebrates, amphibians and reptiles. With regard to habitat fragmentation, this mosaic of habitats is assessed as a single block (Table 13-39). In addition the construction of the residential development will cause some fragmentation of the linkage between the egretry at Shing Uk Tsuen and the Fung Lok Wai fishponds through flightline interference, although it is now apparent that this egretry has been abandoned. This impact is assessed in Table 13-40 in light of the decision to relocate the development eastwards specifically to avoid flightlines.

13.8.12 Prior to construction fencing will be erected around the perimeter of the site. Within construction areas, works area hoarding will also be erected. Perimeter fencing will comprise a chain link fence to prevent unauthorised access to the site. The fence will not be a completely impervious barrier to wildlife, there will be gaps associated with access routes and small animals, such as reptiles and amphibians are expected to pass through the fence unhindered. Birds will be able to pass over the fence and, as it is chain link, it will not obstruct site lines. There is potential, however, for the fence to obstruct the movement of medium and large mammals, such as Eurasian Otter (Lutra lutra) and Crab-eating Mongoose (Herpestes urva). These impacts are considered separately below under Impact on Species of Conservation Importance.

Table 13-39 Summary of Impacts to Wetland Mosaic Habitats (Including Wet Agriculture, Reedbed, and Freshwater Marsh) from Habitat Fragmentation

Criteria Remarks Habitat Quality Mixed:Reedbed – low

Seasonally flooded agricultural land – moderate Permanent freshwater marsh and pools – low to moderate


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Species The mosaic of wetland habitats is of value to fauna groups such as invertebrates, amphibians and reptiles. For the majority of this mosaic the existing direct linkage to Fung Lok Wai fishponds will be retained.

Size/abundance The area of this wetland mosaic is approximately 4.9 hectares. This area will remain intact and most of it will retain direct linkage to the proposed WNR. The eastern-most part of the mosaic will loose direct connection to the Fung Lok Wai fishponds following construction of the residential development. This area will, however, still retain linkage to other parts of the mosaic.

Duration Permanent Reversibility Impact is irreversible Magnitude Low due to maintenance of links with proposed freshwater marsh.

Table 13-40 Summary of Impacts to Fung-shui Woodland from Habitat Fragmentation

Criteria Remarks Habitat Quality Low to Moderate (but high if egretry is present) Species Woodland comprises mixture of native and planted tree and shrub species.

The value of this woodland derives, however, from its use as a nesting site (egretry) by species such as, for example, Little Egret and Chinese Pond Heron. This egretry is now abandoned.

Size/abundance 1.3 hectares of woodland. A survey undertaken in June 2001 indicated that the egretry possessed up to 74 nests located within approximately 0.2 ha of the woodland. More recent inspections indicate that the egretry has been abandoned Construction and operation of the proposed development and WNR will not result in further isolation of the Fung-shui Woodland. Potential impacts on the egretry are considered separately below under Impact on Species of Conservation Importance

Duration None Reversibility No impact Magnitude No Impact

Impact on herons and egrets using egretry is considered below under Impact on Species of Conservation Importance.

13.8.13 In this section Options 1A and 1B are considered to be similar in many respects, the only slight difference between these two options arising from the larger number of buildings in Option 1B. The gaps between buildings will be smaller in this option creating a slightly greater blockage of sightlines for birds. It is predicted, therefore, that Option 1B will result in slightly greater habitat fragmentation than Option 1A. It is emphasised that the difference between these options is slight, particularly in light of the abandonment of the egretry, as it was the potential blockage of flights to and from this feature that was the principal source of concern with respect to habitat fragmentation. Flight line surveys undertaken at the proposed development area did not indicate significant levels of flight for any other bird species and so there is no indication that either option would significantly impact the flightlines of any bird species. Disturbance

13.8.14 Disturbance can be caused during construction and operation phases. Disturbance primarily affects animal species and these impacts are considered in more detail below. For some habitats, however, their importance is largely derived from the species they support. At Fung Lok Wai this includes Aquaculture Ponds and Fung-shui Woodland. The impact of disturbance on these habitats could be significant if it resulted in their supporting reduced populations of Species of Conservation Importance. Disturbance effects arising from glare (sunlight reflecting from glass surfaces during the daytime) and night-time lighting are included in this section. It is expected that light disturbance will only potentially affect bird species. Effects on other species are not expected to be significant.

13.8.15 With respect to glare, as discussed in Chapter 11, construction activities will not extend into the night so night glare during this phase will be very limited. During the operational phase, night-time lighting levels are also expected to be low. The residential development landscape will not require 24 hour lighting except for the lighting of access roads and emergency access. Any


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potential effects of lighting at low levels will be reduced through the use of the proposed landscape buffer along the periphery of the development and roadside planting. The effect of glare at these lower levels can also further reduced through the use of full cut off lighting.

13.8.16 The intensity, luminance and lighting level generated from residential properties is also predicted to be relatively low. The effects of glare (during the day and at night, at all building levels) are considered to be part of the disturbance that will result in the exclusion and disturbance distances identified for individual bird species (see below). It is not predicted that the effects of lighting at night at higher levels of buildings would cause disturbance beyond these disturbance distances.

Table 13-41 Summary of Impacts to Aquaculture Ponds from Disturbance

Criteria Remarks Habitat Quality High Species Disturbance during construction and operation of the residential development

will cause impact to Species of Conservation Importance utilising this habitat, in particular wetland bird species and large birds of prey.

Size/abundance Assessments of the sensitivity of bird species to disturbance including analysis of disturbance effects (see below) indicates that, during construction, the effects of disturbance on the most sensitive species may be detectable up to 500m from source with exclusion expected within 200m. For most species, however, these distances will be lower. During operation, levels of disturbance are expected to be lower and hence disturbance effects for most species will be more limited in their extent. In evaluating the magnitude of disturbance effects, consideration has been given to noise, human presence, daytime glare(from reflective surfaces which may increase the visibility of the residential development during the daytime) and nightime glare (it is assumed that lighting will increase the visibility of buildings at night). The magnitude of glare effects is not expected to be large, the development is located in the south-eastern part of the assessment area, consequently the periods when sunlight will be reflected onto fishpond areas will be limited. Nightime glare is not expected to affect large areas of fishponds as the intensity of lighting used in residential developments is relatively low.

Duration The total construction period for the proposed development is approximately 6 years. During this period the level of disturbance is expected to be discontinuous depending on the specific activities being undertaken (see Chapter 5 for details of noise assessment). The most significant noise generating activities include site formation and foundation works (including piling). The greatest noise levels will, therefore, tend to be experienced in the early stages of construction. Light pollution, to the exent that it will affect fauna, will persist for the lifetime of the development.

Reversibility Reversible Magnitude High

Table 13-42 Summary of Impacts to Fung Shui Woodland (Including Egretry) from Disturbance

Criteria Remarks Habitat Quality Low to Moderate (High if egretry present) Species The egretry within the Fung-shui Woodland is used by some bird species,

including Little Egret and Chinese Pond Heron, for nesting Size/abundance A survey undertaken in June 2001 indicated that the egretry possessed up to

74 nests located within approximately 0.2 ha of the woodland. More recent inspections indicate that the egretry has been abandoned.

Duration The total construction period for the proposed development is approximately 6 years. During this period the level of disturbance is expected to be


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discontinuous depending on the specific activities being undertaken (see Chapter 5 for details of noise assessment). The most significant noise generating activities include site formation and foundation works (including piling). The greatest noise levels will, therefore, tend to be experienced in the early stages of construction. Any disturbance during the breeding season (March to August) will be most significant

Reversibility It is not known to what extent any potential abandonment of the egretry (if present) could be reversed

Magnitude Low (The potential impact of disturbance on the egretry (if present) could be high). The relocated development now lies, at its closest point, 200m from the previous location of the egretry. If the egretry were to re-establish it is possible, considering the sensitivity of the likely nesting species, that noise and vibration created during construction could cause some disturbance. It is unlikely, however, that the operation of the development will cause significant disturbance to any nesting birds. The development has been relocated eastwards to minimise potential flight barrier effects

Table 13-43 Summary of Impacts to Intertidal Forested Wetland from Disturbance

Criteria Remarks Habitat Quality Moderate to high Species No Species of Conservation Importance are likely to be affected Size/abundance The majority of this habitat is considered too remote from the construction

site to be adversely affected by disturbance effects Duration A small area of this habitat (<1 ha.) is located within 400m of the western part

of the proposed construction site. During the early phases of construction it is possible that some disturbance could be experienced within this habitat although the impact is considered to be low

Reversibility Reversible Magnitude Low

Table 13-44 Summary of Impacts to Wetland Mosaic Habitats (including Wet Agriculture, Reedbed, and Freshwater Marsh) from Disturbance

Criteria Remarks Habitat Quality Low to moderate Species The mosaic of wetland habitats is of value to fauna groups such as

invertebrates, amphibians and reptiles. These species are not considered to be sensitive to disturbance effects

Size/abundance Approximately 4.9 ha. Duration Construction and operation phase Reversibility Reversible Magnitude Low

Table 13-45 Summary of Impacts to Dry/Inactive Agricultural Land from Disturbance

Criteria Remarks Habitat Quality Low to moderate Species No Species of Conservation Importance are likely to be affected Size/abundance Small Duration Construction and operation phase Reversibility Reversible Magnitude Low

Table 13-46 Summary of impacts to Semi-natural Secondary Woodland from Disturbance


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Criteria Remarks Habitat Quality Low to moderate Species No Species of Conservation Importance are likely to be affected Size/abundance Small Duration During construction phase Reversibility Reversible Magnitude Low

Pollution

13.8.17 The impacts of potential pollution events arising from the construction and operation of the development on habitats are considered below. The magnitude of the impact pollution events will depend on the nature of the pollutant, its source and the duration of the event.

13.8.18 During construction the main potential source of pollution is from fugitive dust, accidental release of fuel, accidental release of other chemicals associated with construction activities and sediment dispersal from exposed ground.

13.8.19 During operation, the main potential source of pollution impact will arise if a sewage pipe bursts or an emergency by-pass of the sewage pump house is required. The preferred option for the disposal of sewage is Strategy A2 described in Chapter 8. New sewage pipes laid under this strategy (and Strategy A1) follow existing roads and avoid sensitive habitats. In any event the use of twinned sewage pipes will enable the impacts of sewer bursts to be controlled. The risk of significant impact arising from pollution due to pipe failure is, therefore, considered to be extremely small.

13.8.20 Strategy B follows a western route and would involve the laying of pipes beneath the freshwater marsh and adjacent to several Aquaculture ponds to the west of the WNR. As in Strategy A, the use of twinned pipes will enable control of sewage in the event of a burst pipe. Whilst the risk is low, the magnitude of any impact arising because of a sewage leak along this route would be greater than for Strategy A2 (or A1) due to the proximity of sensitive habitats. On ecological grounds, therefore, Strategy A2 is preferred.

13.8.21 All strategies, however, involve the construction of an on-site sewage pump house. In the event of an emergency or power failure, sewage may need to be diverted past this station. To avoid potential impact a by-pass pipe will be installed to direct sewage to the Tai River via Channel “X” thus avoiding the potential for contamination of sensitive freshwater marsh and Fish Pond habitats of the WNR.

13.8.22 There is also potential for light pollution during operation. Sunlight reflecting from glass surfaces during the daytime and from lighting at night could disturb birds. This affect has already been considered under potential disturbance impacts above.

Table 13-47 Summary of Impacts to Aquaculture Ponds from Pollution

Criteria Remarks Habitat Quality High Species Pollution caused by release of toxic chemicals could have a direct impact on

bird Species of Conservation Importance that use this habitat. Size/abundance Although there are about 170.6 ha. of Aquaculture ponds within the

assessment area, a relatively small proportion of these lie adjacent to the development area or in areas that could be affected by residential development construction activities. Construction activities within the WNR primarily involve pond re-profiling and are unlikely to pose a significant pollution risk. The main pollution risk to bund vegetation is from fugitive dust during construction works. If dust is released it is likely to affect a large area depending on its source and prevailing wind directions. No Aquaculture Ponds lie adjacent to the route of sewage strategy A2 (or A1). Three Aquaculture Ponds lie adjacent to Strategy B in the western part


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of the assessment area. Duration Construction and operation phase

The effects of pollution are likely to be persistent, particularly if toxic chemicals are involved or if the pollutant has a tendency to bioaccumulate

Reversibility Generally reversible although duration of recovery will depend on the nature of the pollutant and the magnitude of the event. No highly toxic pollution events are anticipated however

Magnitude Low under preferred sewage strategy (A2) Potentially moderate to large under sewage strategy B, in the event of a sewer pipe burst

Table 13-48 Summary of Impacts to Fung-shui Woodland (including Egretry) from Pollution

Criteria Remarks Habitat Quality Low (High if egretry present) Species Species of Conservation Importance, including nesting herons and egrets,

could potentially be affected Size/abundance A survey undertaken in June 2001 indicated that the egretry possessed up to

74 nests located within approximately 0.2 ha of the woodland. More recent inspections indicate that the egretry has been abandoned. The main pollution risk to the Fung-shui Woodland (and egretry if present) is from fugitive dust during construction works. Potentially all of the 1.25 hectares of Fung-shui woodland is at risk from dust pollution, although the magnitude of this risk will depend on the dust source and prevailing wind directions.

Duration Construction phase only. Impacts that occur during the egret breeding season (if egretry present) would be of greater magnitude

Reversibility Largely reversible – any impacts to egretry (if present) may be irreversible Magnitude Low (High if egretry present)

Table 13-49 Summary of Impacts to Intertidal Forested Wetland from Pollution

Criteria Remarks Habitat Quality Moderate to high Species Species of Conservation Importance could potentially be affected Size/abundance 45.3 ha. present within the Assessment Area.

The risk of chemical pollution to this habitat is low due to its remote location from the construction site and proposed sewer strategies. The main pollution risk, therefore, is fugitive dust during construction works. If dust is released it is likely to affect a large area depending on its source and prevailing wind directions.

Duration Construction phase only Reversibility Reversible Magnitude Moderate

Table 13-50 Summary of Impacts Wetland Mosaic Habitats (including Wet Agriculture, Reedbed, and Freshwater Marsh) from Pollution

Criteria Remarks Habitat Quality Low to moderate Species Species of Conservation importance could potentially be affected Size/abundance The small wetland mosaic in the south-western part of the assessment area is

located close to the proposed construction site of the residential development. All of this mosaic is potentially at risk from accidental pollution events during construction During operation there is a small risk of pollution arising from contamination by sewage in the event of a pipe burst. Neither of the strategies considered, however, involve placing pipes in close proximity to these habitats and, in any event the use of twinned sewage pipes ensures that any burst is controllable


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Duration Construction and operation phase The effects of pollution are likely to be persistent, particularly if toxic chemicals are involved or if the pollutant has a tendency to bio-accumulate

Reversibility Generally reversible although duration of recovery will depend on the nature of the pollutant and the magnitude of the event. No highly toxic pollution events are anticipated however and the risk of large scale pollution events due to dust or sediment dispersal is considered low

Magnitude Moderate

Table 13-51 Summary of Impacts to Dry/Inactive Agricultural Land from Pollution

Criteria Remarks Habitat Quality Low to moderate Species No Species of Conservation Importance are likely to be affected Size/abundance The main pollution risk to the small areas of this habitat within the assessment

area is from fugitive dust during construction works. The magnitude of this risk will depend on the dust source and prevailing wind directions


Table 13-52 Summary of Impacts to Semi-natural Secondary Woodland from Pollution

Criteria Remarks Habitat Quality Low to moderate Species No Species of Conservation Importance are likely to be affected Size/abundance The main pollution risk to this habitat is fugitive dust during construction

works. If dust is released it is likely to affect a large area depending on its source and prevailing wind directions


Soil Compaction

13.8.23 The use of heavy machinery during construction works could result in the compaction of soils on the bunds associated with the existing aquaculture pond bunds.

Table 13-53 Summary of Impacts to Aquaculture Ponds from Soil Compaction

Criteria Remarks Habitat Quality High Species No Species of Conservation Importance likely to be affected Size/abundance Potentially affects those pond bunds that will not be removed during

construction within the development area and conversion of aquaculture ponds to freshwater marsh. A large proportion of the remaining pond bunds could be affected by soil compaction associated with the use of heavy machinery during the removal and modification of pond bunds associated with pond enhancement works

Duration Construction phase only Reversibility Reversible Magnitude Low

Hydrological disruption

13.8.24 The proposed development will involve the diversion of some existing Ditches and Drainage Channels. As these habitats were found to be of low quality and the extent of habitat affected is low, the impact of hydrological diversion to this habitat is also considered to be low.


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Table 13-54 Summary of Impacts to Ditches and Drainage Channels from Hydrological Disruption

Criteria Remarks Habitat Quality Low Species The drainage channels on site are of low water quality and support no Species

of Conservation Importance Size/abundance Approximately 0.02 hectares will be removed and a short stretch will be

diverted. Remaining stretches will be used to manage water levels within the proposed WNR

Duration Permanent Reversibility Impact is irreversible Magnitude Low

Summary of Potential Impacts on Habitats During Construction

13.8.25 There will be no net loss of water body in the WCA or WBA. Permanent habitat loss of aquaculture ponds due to the development footprint will be compensated by re-profiling aquaculture ponds, thus creating enlarged ponds of higher ecological value, and freshwater marsh, also of higher ecological value. The pond enhancement works are likely to cause some compaction of bunds during construction activities, particularly in relation to the removal and modification of bunds during the WNR development. The significance of this impact is, however, considered to be low in light of the low intrinsic value of bunds within the aquaculture pond habitat.

13.8.26 No significant habitat fragmentation is anticipated as a consequence of the proposed development. The potential for obstruction of flightlines of any herons and egrets that may nest at the egretry at Shing Uk Tsuen (now apparently abandoned) is considered under Impacts on Species of Conservation Importance below

13.8.27 The major effect of disturbance caused by construction of the proposed development will be on sensitive bird species. During construction, areas of Aquaculture Pond habitat close to the Proposed Development Area are expected to support significantly reduced populations of wetland Species of Conservation Importance, this potential impact is considered in more detail under Impacts on Species of Conservation Importance below.

13.8.28 There is a potential risk of pollution to some habitats through, for example, accidental releases of chemicals or dust during construction. The habitats most at risk from accidental release of pollutants such as fuel or chemicals are those in the immediate vicinity of the development area or that are linked to the development area hydrologically. These include Aquaculture Ponds, Drainage Ditches and Channels and Wetland Mosaic Habitats (including Wet Agriculture, Reedbed, and Freshwater Marsh).

13.8.29 Most habitats within the assessment areas are at some risk from the effects of fugitive dust created during construction activities, including, potentially, Aquaculture Ponds, Intertidal Forested Wetland and Fung-shui Woodland. The potential impacts of smothering from dust are considered to be moderate because, whilst they may be locally intense, they are also temporary in nature and reversible.

13.8.30 During construction the potential effects of Options 1A and 1B are considered to be the same. Summary of Potential Impacts on Habitats During Operation

13.8.31 The key potential impacts associated with the operational phase of the development include disturbance, habitat fragmentation and pollution arising from operation of the sewerage system.

13.8.32 During operation areas of Aquaculture Pond habitat close to the Proposed Development Area are expected to support significantly reduced populations of wetland Species of Conservation Importance, due to disturbance caused by human presence, noise and lighting. This potential impact is considered in more detail under Impacts on Species of Conservation Importance below.

13.8.33 The presence of tall built structures could obstruct flightlines of birds, particularly herons and egrets and reduce accessibility to important feeding areas. This potential impact is considered in


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more detail under Impacts on Species of Conservation Importance below.

13.8.34 The risk of pollution from the operation of the sewerage system is considered to be low. Under the preferred strategy (A2) new sewer pipes will follow existing roads, furthermore the use of twinned pipes will ensure that the possibility of significant leakage is minimised in the event of a pipe burst. Under strategy B the same precautions would be taken but the proximity of the pipe route to sensitive Aquaculture Pond habitat means that the consequences of a leak, although unlikely, would be more significant.

13.8.35 In the event of an emergency by-pass of the sewage pump house, sewage would be directed to the Tai River via a pipe to Channel X. Although this would avoid disposing of untreated sewage to sensitive habitats within the WNR, there would be short-term intensive impact to a short stretch of Ditches and Drainage Channel habitat, a habitat of low intrinsic value. There would also be a temporary impact to the Tai River (Permanent Rivers, Streams and Creeks habitat). Dilution effects, the existing poor water quality of the Tai River and the expected short duration of by-pass events ensure, however, that long-term significant impact to this habitat is unlikely.

13.8.36 The potential effects of Options 1A and 1B during the operational phase are considered to be similar in many respects, the only slight difference between these two options arising from the larger number of buildings in Option 1B. The gaps between buildings will be smaller in this option creating a slightly greater blockage of sightlines for birds. It is predicted, therefore, that Option 1B will result in slightly greater habitat fragmentation than Option 1A. It is emphasised that the difference between these options is slight, particularly in light of the abandonment of the egretry, as it was the potential blockage of flights to and from this feature that was the principal source of concern with respect to habitat fragmentation. Assessment of Potential Impacts on Species of Conservation Importance

13.8.37 The assessment of impacts on habitats above indicates that there are effects arising from the construction and operation of the proposed development that will have an impact on animal species, in particular: • Habitat loss; • Disturbance caused by the construction and operation of the proposed development,

including mitigation associated with the construction of the Wetland Nature Reserve (WNR). In order to minimise the effects of habitat loss and disturbance key works associated with the WNR will be undertaken before the commencement of construction of the residential development. The potential disturbance associated with these works is also considered in this section; and,

• Fragmentation – in particular the obstruction of flightlines of birds moving to and from the egretry.

Habitat Loss

13.8.38 It is anticipated that the key habitat likely to be directly affected by the proposed residential development is Aquaculture Ponds. It is predicted that approximately 4.0 ha of aquaculture ponds will be permanently lost within the Development Area. In addition there will be temporary habitat loss during the construction of the WNR arising from: • Construction of the Marsh Habitat and the approximately 1 year of establishment required for

this habitat (approximately 14.4 ha). • Enlargement of ponds, which will involve the simultaneous temporary drainage of 2 or 3

ponds to enable bund removal and re-profiling.

13.8.39 The relative timing of the construction of the key elements of the WNR and the residential development is shown in Figure 13-13. The construction of the WNR is divided into Sectors as described in Section 13.9. At each stage the maximum area of pond unavailable due to construction works is shown along with the remaining area unaffected by construction works. During construction the period during which the most area is unavailable (approximately 22.2 ha) is between April 2011 and October 2011 when the Development Area, the Marshland (which will be establishing) and some Sector 3 ponds will be concurrently unavailable. This represents a maximum temporary loss of approximately 28% of the total wetland habitat present within the Study Site.


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13.8.40 The species most likely to be affected by permanent and temporary habitat loss are birds, particularly waterbirds. It is envisaged that there will be adequate remaining wetland within the Study Area, and adjacent areas, to accommodate birds permanently displaced from the Development Area (which represent approximately 5% of the total wetland area within the Study Site) and temporarily displaced from the Aquaculture Ponds and WNR construction areas. To ensure that the carrying capacity of the remaining wetland areas is sufficient for these species an interim management programme will be implemented intended to significantly improve feeding opportunities for waterbirds, particularly ardeids (see below).

13.8.41 It is anticipated that permanent and temporary habitat loss will reduce the availability of foraging habitat for Imperial Eagle, Great Spotted Eagle and Osprey. The significance of this impact is considered to be low due to the scarcity of these species at Fung Lok Wai and their large foraging ranges. This conclusion is reached on the basis of the following: 1) During the 12 months baseline survey there were very few records of these species within the

survey area. In fact there were no records of Great Spotted Eagle or Osprey utilising habitats within the proposed areas for the Residential Development nor the WNR. These species were either observed overflying the general Fung Lok Wai area or were observed within the wider assessment area (ie within the 500m buffer around the EIA study area WNR). It is clear, therefore, that the 12 months survey did not find any evidence that these species have any particular reliance upon the ponds potentially affected by the proposed Residential Development or WNR. As indicated for other species there is no indication that the importance of these ponds would have increased in importance during the period since the 12 months survey was undertaken (see Appendix 13-12).

2) To the extent that Imperial Eagle, Great Spotted Eagle and Osprey are likely to forage within the study area, then it has been assumed in the EIA report that noise and human presence will cause disturbance during construction and operation. The magnitude of the displacement effect arsing from this disturbance is evaluated in Table 13-56 (construction) and Table 13-57(operation) (see below). For the purpose of these evaluations it has been assumed that raptors are amongst the most sensitive species present and that any effect would detectible upto 500m from the source of disturbance. These tables, in summary, indicate that the maximum area of habitat affected would be 51.4 ha during construction and operation for each of the three species. As indicated above though this represents displacement from an area upon which these species show little reliance.

3) The effect of this displacement on Imperial Eagle, Great Spotted Eagle and Osprey is not considered to be of anything other than low significance because: • None of these species shows great reliance upon the habitats potentially affected • There is extensive alternative habitat for these species within the New Territories – all

three species forage over large areas. EPD indicate that the extent of freshwater wetland in Hong Kong is approximately 10,000ha and the area affected by this development, therefore, represents about 0.5%. This does not take account of inter-tidal habitats that these species may also rely upon.

• The mitigation proposed for the construction and operational phases aims, in any case, to increase the numbers of wetland birds within those areas that are not affected by operational disturbance. This will include waterfowl that comprise prey for the eagle species and fish, that are preyed upon by Osprey.

13.8.42 Crested Serpent Eagle is less dependent on wetland habitats than the other raptor species recorded. The significance of permanent and temporary habitat loss for Crested Serpent Eagle is, therefore, considered to be very low.

13.8.43 It is considered that the impacts of both Options 1A and 1 B will be similar with respect to habitat loss for these raptor species.

13.8.44 There are several Species of Conservation Importance that are dependent on bund habitats, the most important of which are, Red-billed Starling, Collared Crow and Cattle Egret. The development of the WNR will result in the removal of some bunds (as indicated in Figure 14-6). The potential impact of bund removal on these species is considered to be of low magnitude, however, for the following reasons: • Red-billed Starling and Collared Crowe were recorded in relatively low numbers within the


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study site. Extent of bund habitat is unlikely to be the key limitiation on the population size of these species.

• Cattle Egret were recorded in highest numbers in the north-western part of the study site on ponds that are adjacent to the Tai River, the location where there would be no bund removal works (see Figure 14-6).

13.8.45 The other Species of Conservation Importance potentially affected by the construction of the Residential Development and the WNR are reptiles. The effects on these species are considered to be of low magnitude because: • The works will be undertaken progressively ensuring that the area affected at any one time is

relatively small. • There are abundant areas of alternative habitat for these species. • The baseline surveys established that the key areas of importance for these species tended to

be located in the buffer zone (ie outside the Development Area and location of the WNR).

13.8.46 It is considered that the impacts of both Options 1A and 1 B will be similar with respect to habitat loss for all Species of Conservation Importance. Disturbance

13.8.47 Disturbance can arise from works associated with the construction of the Residential Development and the WNR. In addition it is anticipated that there will be disturbance arising from the ongoing operation of the Residential Development, although this is expected to be of a lesser magnitude than that arising from construction activities. The operation of the WNR is expected to be beneficial for Species of Conservation Importance

13.8.48 The species most likely to be affected by disturbance impacts are Species of Conservation Importance birds (particularly flock feeding waterbirds, larger herons and birds of prey), and to less of an extent, reptiles. Such species are likely to be disturbed by loud noises, moving objects, the presence of people, glare from reflective surfaces and night-time lighting. Stationary objects such as buildings are also sources of disturbance as these may obscure flight lines and views of potentially approaching predators. Other species that could be affected are mammals. However, no large mammals were recorded during the field surveys and therefore particular attention will be focussed on bird Species of Conservation Importance recorded on site.

13.8.49 An assessment of the predicted impacts of disturbance on each Species of Conservation Importance that regularly occurs in significant numbers has been carried out. The assessment is based on a combination of literature review, analysis of field survey data and experience of the study team and previously accepted assessment criteria. The magnitude of disturbance effects, including night-time glare, has been evaluated on the basis of disturbance distances. It has been assumed that disturbance effects (including night-time glare) will result in a zone around the residential development where sensitive species will: a) be excluded; and b) occur in reduced densities. The effects of night glare are integrated into the assessment because it is assumed that the extent of the exclusion or reduced density zones will be maintained through the day and night (24hrs). During the day noise and human presence are expected to be the main disturbance factors, at night light will be a factor. As light will not be directed into the WNR, there is no reason to believe that the magnitude of light glare would exceed that of day-time disturbance effects. In fact, there is evidence that artificial light can benefit some birds, including waders. Wading birds that feed by sight, for example, use artificial illumination of foraging habitats to extend the period within which they able to forage. Disturbance impacts have been calculated by defining distance from the edge of the disturbance source to the furthest point of: • An exclusion zone – the area adjacent to the source of disturbance and from which a species

are expected to be completely excluded; and • A zone of reduced density – Where the numbers of a species are lower than they would be in

the absence of disturbance either because it occurs in lower numbers (more tolerant individuals) and/or for a shorter period of time (for example during periods of reduced human activity).

13.8.50 The distances at which these effects occur vary from species to species, depending on their sensitivity as indicated in Table 13-53.


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13.8.51 Subsequent assessments of disturbance effects on Species of Conservation Importance are based on the extent of habitat loss, or functional habitat loss, arising because species are excluded from, or occur in reduced densities within, habitats that would be otherwise suitable for them. The extent functional habitat loss will be greater for more sensitive species than it is for species that are considered to disturbance tolerant. The extent of functional habitat loss has been calculated by assuming that the utilisation of habitats within the exclusion zone is 0%. In other words the functional habitat loss in this zone is 100%. Beyond this, in the zone of reduced density, utilisation is considered to be 50% of that within undisturbed areas (based on the assumption that there will be 0% utilisation at the border with the avoidance zone rising to 100% utilisation at the border with the undisturbed areas). The overall extent of functional habitat loss is, therefore, calculated by adding 100% of the area within the exclusion zone + 50% of the area within the zone of reduced density. The extent of habitats affected in this way have been calculated using GIS.

13.8.52 This approach is used because it provides an integrated way of considering all disturbance effects, including, for example, noise, human presence, day-time glare and night-time lighting effects. The approach is conservative because the disturbance distances are considered to be cautious.

13.8.53 The predicted disturbance distance for regularly occurring Species of Conservation Importance are shown in Table 13-55 and presented in Figure 13-12.

Table 13-55 Predicted Disturbance Impacts from the Construction and Operation of the Residential Development on Regularly Occurring Species of Conservation Importance at Fung Lok Wai

Construction phase Operation phase Exclusion

distance (m) Max distance

of reduced density (m)

Exclusion distance

(m)

Max distance of

reduced density (m)

Sensitivity to disturbance

Black-faced Spoonbill

200 400 100 200 High

Greater Spotted Eagle

200 500 200 500 Very High

Imperial Eagle 200 500 200 500 Very High Red-billed Starling

100 200 50 100 Moderate

Common Teal 100 300 50 100 Moderate-High Eurasian Wigeon 100 300 50 100 Moderate-High Osprey 200 500 200 500 Very High Black Kite 50 100 20 30 Low Chinese Pond Heron

100 300 20 30 Moderate

Great Cormorant 200 400 100 150 High Great Egret 200 400 100 200 High Little Egret 100 400 20 100 Moderate-High Black-crowned Night Heron

50 100 20 30 Low

Cattle Egret 50 100 20 30 Low Grey Heron 100 300 20 30 Moderate Striated Heron 100 300 20 30 Moderate Collared Crow 50 100 20 30 Low Crested Serpent Eagle

200 500 200 500 Very High

Little Grebe 100 200 50 50 Moderate-High Little Ringed Plover

100 200 50 50 Moderate-High

Pied Kingfisher 50 100 20 30 Low Temminck’s 100 200 50 50 Moderate-High


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Stint White-throated Kingfisher

50 100 20 30 Low

Wood Sandpiper 100 200 50 50 Moderate-High

13.8.54 Analysis of the susceptibility of Species of Conservation Importance to disturbance above indicates that four species of raptor Imperial Eagle, Greater Spotted Eagle, Osprey and Crested Serpent Eagle and three species of large waterbird, Black-faced Spoonbill, Great Cormorant and Great Egret are most susceptible.

13.8.55 Of these species, the four birds of prey range widely in the Deep Bay area and are known to exhibit marked avoidance of man-made structures. Single individuals of Imperial Eagle, Greater Spotted Eagle, Crested Serpent Eagle and Osprey were recorded flying over Fung Lok Wai on a maximum of three occasions throughout the twelve months of survey and hence are not considered likely to have a significant dependence on the site. In addition results of a recent survey of Imperial and Greater Spotted Eagle (KCRC & BBVHK 2002) indicate that these species have a significant preference for managed wetland (e.g. Mai Po) and neither showed a significant preference for fishpond habitat.

13.8.56 The key habitat for the remaining species within the assessment area are Aquaculture Ponds.

13.8.57 Construction activity associated with the Residential Development will commence during the second half of 2013. The construction of the residential development will result in the permanent loss of approximately 4.0 ha of aquaculture ponds. During the early stages of construction the created Freshwater Marsh habitat will not be fully established and this area (approximately 14.4 ha) is also assumed to be temporarily unavailable.

13.8.58 In addition, it is anticipated that disturbance caused, primarily by human presence, noise and vibration during the construction of the residential development will result in a reduced density of birds adjacent to the development. The maximum distance of reduced density (as indicated in Table 13-55) is expected to be 500m for the most sensitive Species of Conservation Importance (for example, Osprey) and 100m for the least sensitive (including, for example, White-throated Kingfisher). The additional temporary habitat loss caused by construction activities associated with the construction of the residential development will range, therefore, between approximately 33.0 ha and 2.0 ha depending on the sensitivity of the species. Taking into account the loss of approximately 4.0ha due to the construction of the Residential Development and the temporary unavailability of approximately 14.4 ha during construction of the Freshwater Marsh area, this amounts to between 51.4 ha and 20.4 ha, respectively. It should be noted, however, that these figures are considered to be over-estimates. It is unlikely that development will proceed in all parts of the development area simultaneously reducing the area affected by disturbance at any one time.

13.8.59 Table 13-56 identifies the permanent and temporary habitat loss during the construction phase for each of the regularly occurring Species of Conservation Importance. These impacts have been calculated on the assumption that there will be low level visual human disturbance and that basic mitigation measures, including the creation of wetland habitats with reedbeds and the planting of trees and bamboo as screening will be implemented.

Table 13-56 Habitat Loss During the Construction Phase on Regularly Occurring Species of Conservation Importance at Fung Lok Wai

Species Maximum distance of

reduced density during construction

(m)

Permanent habitat loss

(ha)

Temporary habitat loss

due to marsh construction

(ha)


due to construction disturbance

(ha)

Maximum area of habitat

affected (ha)

Black-faced Spoonbill 400 4.0 14.4 23.4 41.8 Greater Spotted Eagle 500 4.0 14.4 33.0 51.4


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Species Maximum distance of

reduced density during construction

(m)

Permanent habitat loss

(ha)


due to marsh construction

(ha)


due to construction disturbance

(ha)

Maximum area of habitat

affected (ha)

Imperial Eagle 500 4.0 14.4 33.0 51.4 Red-billed Starling 200 4.0 14.4 6.4 24.8 Common Teal 300 4.0 14.4 12.0 30.4 Eurasian Wigeon 300 4.0 14.4 12.0 30.4 Osprey 500 4.0 14.4 33.0 51.4 Black Kite 100 4.0 14.4 2.0 20.4 Chinese Pond Heron 300 4.0 14.4 12.0 30.4 Great Cormorant 400 4.0 14.4 23.4 41.8 Great Egret 400 4.0 14.4 23.4 41.8 Little Egret 400 4.0 14.4 19.9 38.3 Black-crowned Night Heron

100 4.0 14.4 2.0 20.4

Cattle Egret 100 4.0 14.4 2.0 20.4 Grey Heron 300 4.0 14.4 12.0 30.4 Striated Heron 300 4.0 14.4 12.0 30.4 Collared Crow 100 4.0 14.4 2.0 20.4 Crested Serpent Eagle 500 4.0 14.4 33.0 51.4 Little Grebe 200 4.0 14.4 6.4 24.8 Little Ringed Plover 200 4.0 14.4 6.4 24.8 Pied Kingfisher 100 4.0 14.4 2.0 20.4 Temminck’s Stint 200 4.0 14.4 6.4 24.8 White-throated Kingfisher

100 4.0 14.4 2.0 20.4

Wood Sandpiper 200 4.0 14.4 6.4 24.8

13.8.60 Once construction of the residential development is complete it is anticipated that there will be ongoing disturbance, at a significantly reduced level, associated with the operation of the site.

13.8.61 For the purposes of this assessment the operational phase disturbance impact has been estimated on the basis of the disturbance distances (operation phase) in Table 13-53 The distances of reduced density are considered to be lower for the key species listed than during the construction phase. This is because: • The intensity of noise and vibration during ongoing use are expected to be much lower than

during construction which requires the use of heavy machinery; • Noise and vibration tend to be more continuous than during construction and some level of

habituation is expected; and, • There will be screening at ground level reducing the visibility of residents to birds within the

WNR.

13.8.62 In addition it has been assumed that the area of the residential development (4.0 ha) is unavailable and that the created marsh habitat (c. 14.4 ha) will continue to be unavailable. In practice though it is expected that the marsh habitat will be fully established by the time that the development is occupied and will provide additional habitat for the Species of Conservation Concern potentially affected by disturbance effects. Consequently the following assessment of disturbance impacts during operation is highly precautionary. The expected habitat loss predicted during the operation phase is indicated in Table 13-57.


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Table 13-57 Habitat Loss during the Operation Phase on Regularly Occurring Species of Conservation Importance at Fung Lok Wai

Species Operation phase max distance of reduced density (m)

Permanent habitat loss (ha)

Temporary habitat loss during marsh establishment (ha)

Functional habitat loss due to operational disturbance (ha)

Total (ha)

Black-faced Spoonbill 200 4.0 14.4 6.4 24.8

Greater Spotted Eagle 500 4.0 14.4 33.0 51.4

Imperial Eagle 500 4.0 14.4 33.0 51.4

Red-billed Starling 100 4.0 14.4 2.0 20.4

Common Teal 100 4.0 14.4 2.0 20.4

Eurasian Wigeon 100 4.0 14.4 2.0 20.4

Osprey 500 4.0 14.4 33.0 51.4

Black Kite 30 4.0 14.4 0.8 19.2

Chinese Pond Heron 30 4.0 14.4 0.8 19.2

Great Cormorant 150 4.0 14.4 4.5 22.9

Great Egret 200 4.0 14.4 6.4 24.8

Little Egret 100 4.0 14.4 1.8 20.2

Black-crowned Night Heron

30 4.0 14.4 0.8 19.2

Cattle Egret 30 4.0 14.4 0.8 19.2

Grey Heron 30 4.0 14.4 0.8 19.2

Striated Heron 30 4.0 14.4 0.8 19.2

Collared Crow 30 4.0 14.4 0.8 19.2

Crested Serpent Eagle 500 4.0 14.4 33.0 51.4

Little Grebe 50 4.0 14.4 1.1 19.5

Little Ringed Plover 50 4.0 14.4 1.1 19.5

Pied Kingfisher 30 4.0 14.4 0.8 19.2

Temminck’s Stint 50 4.0 14.4 1.1 19.5


30 4.0 14.4 0.8 19.2

Wood Sandpiper 50 4.0 14.4 1.1 19.5

13.8.63 In the absence of mitigation, the potential impacts of the proposed development on Species of Conservation Importance due to habitat loss and disturbance are likely to be significant. The magnitude of these impacts is greatest during construction but the effects will be temporary. During operation the magnitude of impacts on Species of Conservation Importance is less but the effects will be permanent, although over time it is expected that bird populations will habituate to disturbance to some extent.

13.8.64 A key aspect of this proposal is the construction of a WNR to compensate for impacts associated with habitat loss and disturbance. The strategy, programme and specific actions associated with the construction and operation of the WNR are addressed in detail in Section 13.9 (Mitigation). That section also identifies likely disturbance effects that potentially arise from the construction of the WNR itself.

13.8.65 It is considered that the disturbance impacts on birds (including raptors) and other wildlife arising


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from both Options 1A and 1 B will be the same. Habitat Fragmentation

13.8.66 The impact of any development on bird flight lines is unclear. Birds are extremely mobile and will undoubtedly seek to avoid obstructions. Furthermore, the construction time for a high rise development is typically in the order of months to years providing opportunity for birds, even those that may have habituated to flying certain routes, to find alternative flight lines to foraging or roosting sites.

13.8.67 Surveys of bird flightlines undertaken during the baseline study indicated that the proposed development was in-line with a small proportion of flight paths of birds moving to and from the egretry at Shing Uk Tsuen (located to the south-west of the Study Site). More recent observations now indicate that this egretry has been abandoned (Anon 2005) eliminating potential impacts on this feature. In addition the in-filling of ponds required to enable the construction will reduce flight activity in the area of the proposed Residential Development due to the removal of foraging opportunities in that area (see impacts associated with habitat loss and disturbance).

13.8.68 Analysis of data collected when the egretry was occupied indicated that approximately 24% of observed flightlines originating from, or terminating at, the egretry passed through the zone occupied by the current Proposed Development Area (Figure 13-11).

13.8.69 Comparison of alternative development options (see section 13.6 above) indicated that it was possible to reduce the potential impact of the residential development on these flightlines by shifting the Development Area eastwards. As a consequence a decision was taken to move the development 150m eastwards of its original location, leading to a reduction in flightline intersection from 65% to 24%. The relocated development area is at the periphery of the study site and does not now, in the absence of the egretry, lie between areas of habitat that are important for waterbirds.

13.8.70 Additionally the following mitigation is also intrinsic to the design of the development: • Adoption of a building design that emphasises fewer taller buildings (consistent with height

constraints) rather than many smaller buildings. This enables gaps to be maintained between buildings preserving sight lines for birds moving within the site.

• Construction of a potential alternative egretry within the WNR. The provision of this feature will encourage any nesting birds to occupy a site that is within the central part of the fishpond area, thus potentially eliminating the need for flights through the development area. It should be noted that there is no precedent for the re-establishment of egretries that have been abandoned in Hong Kong (G. Carey, pers comm.).

13.8.71 The results of the flightline surveys (see Table 13-33 and Table 13-34) indicate that, other than ardeids, there were few flightlines arising from other species passing through the proposed area of the Residential Development. On this basis it is considered that there is no indication that there would be a significant fragmentation effect on any bird species arising from the construction and operation of the Residential Development.

13.8.72 A potential additional effect of the construction of mid-rise buildings relates to the obstruction of sight lines. This would occur if buildings prevented birds seeing habitats that might otherwise seek to forage within. This is primarily likely to affect Greater Spotted Eagle and Imperial Eagle which are likely to perch on higher ground (as found to the south of Fung Lok Wai) prior to foraging over wetland areas. This effect is likely to be of lesser importance for Crested Serpent Eagle which is less reliant on wetland habitats than Greater Spotted Eagle and Imperial Eagle. It is of least importance to Osprey which does not typically seek out higher ground for any purpose.

13.8.73 The significance of the potential impact arising from the blockage of sight lines is considered to be low for Greater Spotted Eagle and Imperial Eagle due to their demonstrated low reliance upon the wetland habitats at Fung Lok Wai. It should be noted that baseline ornithological surveys included hillside habitats (Transect 6) and raptors (including the eagle species) were rarely recorded in this area.

13.8.74 With respect to Crested Serpent Eagle and Osprey the potential effect is considered to be insignificant due to the behaviour of these species which implies that sightline blockage will be


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negligible.

13.8.75 Although both Option 1A and 1B involve the construction of mid-rise buildings, there will be a greater number of more closely spaced buildings in Option 1B than in Option 1A. Conversely the buildings in Option 1A will be slightly higher (14-18 stories) than those proposed in Option 1B (all 15 stories). It is considered that the effects of reducing the spacing of buildings will reduce sightlines to a greater extent than the slight differences in building height proposed. On this basis it is concluded that Option 1B will have a slightly greater impact, with respect to this effect, than Option 1A. It should be noted, however, that the potential impact of both options is considered to be low for Greater Spotted Eagle and Imperial Eagle and insignificant for Osprey and Crested Serpent Eagle.

13.8.76 In light of the relocation of the development, the abandonment of the Shing Uk Tsuen egretry, the proposed mitigation and the likely reduction in flight activity within the proposed Residential Development Area once the existing ponds have been in-filled (to enable construction), it is anticipated that the effect of flightline obstruction will be minor. In Option 1B the gaps between buildings will be smaller than in Option 1A creating a slightly greater blockage of sightlines for birds. It is predicted, therefore, that flightline obstruction (and hence habitat fragmentation) in Option 1B will be slightly greater than in Option 1A. It is emphasised, however, that the difference between these options is slight, particularly in light of the abandonment of the egretry, as it was the potential blockage of flights to and from this feature that was the principal source of concern.

13.8.77 There is no indication that the construction of the residential development would result in the fragmentation of the habitat for any animal species (other than birds). The location of the development, at the periphery of the wetland area, will not create a barrier to the movement of wildlife associated with wetland habitats (or any other habitat type). In this resect there is no difference between Options 1A or 1B and both are considered to have an insignificant impact with respect to habitat fragementation for non-avian species.

13.8.78 Another potential source of fragmentation that could affect Species of Conservation Importance is the erection of fencing around the perimeter of the site and the erection of works area hoarding around construction areas.

13.8.79 Perimeter fencing will comprise a chain link fence to prevent unauthorised access to the site. The fence will not be a completely impervious barrier to wildlife, there will be gaps associated with access routes and small animals, such as reptiles and amphibians are expected to pass through the fence unhindered. Birds will be able to pass over the fence and, as it is chain link, it will not obstruct site lines. There is potential, however, for the fence to obstruct the movement of medium and large mammals, such as Eurasian Otter (Lutra lutra) and Crab-eating Mongoose (Herpestes urva).

13.8.80 Neither species was observed during the baseline surveys, but they are known to be present in similar habitats in the Deep Bay area. Whilst there is potential for fencing around the site to obstruct the movement of species such as these, the magnitude of this impact is not expected to be high as existing security fencing to the north-west and north-east of the site (along the banks of the Shan Pui River) has already effectively isolated Fung Lok Wai from potential adjacent habitats for these species. Nevertheless some reduced movement of medium to large mammal species is anticipated between Fung Lok Wai and adjacent habitats due to perimeter fencing.

13.8.81 The erection of works area hoarding is not anticipated to cause impact to wildlife by obstructing movement as it will be located around areas within which construction is taking place and which are not expected (once works commence) to provide habitat for any Species of Conservation Importance. Other Species

13.8.82 Five non-bird Species of Conservation Importance were identified in low numbers within the Assessment Area, Banded Krait, Common Rat Snake, Indo-Chinese Rat Snake, Many-banded Krait and Mangrove Water Snake (see section 13.6). Of these Common Rat Snake (Ptyas mucosus), Indo-Chinese Rat Snake (Ptyas korros) and Mangrove Water Snake are expected, on the basis of their habitat preferences and baseline survey data, to have the greatest reliance on the area of fishponds that will be enhanced during construction of the Wetland Nature Reserve. The


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other snake Species of Conservation Importance tended to show a greater preference for mangrove, hillside and agricultural habitats that will be unaffected by the proposed development.

13.8.83 The sensitivity of reptile Species of Conservation Importance is not known. It is expected that these species will avoid areas close to the development area where there is increased human presence and the effects of noise and vibration are likely to be greatest. Given the low observed abundance of these species it is expected, however, that individuals affected by disturbance can readily relocate to other parts of Fung Lok Wai and adjacent suitable habitat that is also present within the 500m Buffer Zone. Summary of Potential Impacts on Species of Conservation Importance

13.8.84 The key potential impacts on Species of Conservation Importance arising from construction and operation of the Residential Development are permanent and temporary habitat loss. These impacts arise from the permanent conversion of ponds within the Proposed Development Area and disturbance caused by noise and vibration created during construction activities in the first instance and then noise and increased human presence during the occupation (operation) of the development in the long-term. The Species of Conservation Importance most affected by these impacts are expected to be birds. Reptiles, observed to be present only in low numbers, are unlikely to be significantly affected. A summary of the significance of potential impacts on Species of Conservation Importance are presented in Table 13-58.

Table 13-58 Significance of impacts on Species of Conservation Importance at Fung Lok Wai

Species of Conservation Interest Evaluation

Common Name Scientific Name Construction Phase Impacts

Operation Phase Impacts

Avifauna Black-faced Spoonbill Platalea minor High Moderate Greater Spotted Eagle* Aquila clanga Low Low Imperial Eagle* Aquila heliaca Low Low Red-billed Starling Sturnus sericeus Low Low Common Teal Anas crecca Low Very Low Eurasian Wigeon Anas Penelope Moderate Low Osprey* Pandion haliaetus Low Low Black Kite Milvus migrans Low Low Chinese Pond Heron Ardeola bacchus Moderate Moderate Great Cormorant Phalacrocorax carbo High Low to moderate Great Egret Egretta alba High Moderate Little Egret Egretta garzetta High Moderate Black-crowned Night Heron Nycticorax nycticorax Low Low Cattle Egret Bubulcus ibis Low to moderate Low to moderate Grey Heron Ardea cinerea Moderate Moderate Striated Heron Butorides striatus Very Low Very Low Collared Crow Corvus torquatus Very low Low Crested Serpent Eagle* Spilornis cheela Low Low Little Grebe Tachybaptus ruficollis Low Low Little Ringed Plover Charadrius dubius Low Low Pied Kingfisher Ceryle rudis Very Low Very Low Temminck’s Stint Calidris temminckii Low Low White-throated Kingfisher Halcyon smyrnensis Low Low Wood Sandpiper Tringa glareola Very Low Very Low

Herpetofauna Common Rat Snake Ptys mucosus Low Low Indo-Chinese Rat Snake Ptys korros Low Low Mangrove Water Snake Enhydris bennettii Low Low


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* Survey data indicate that these species only occur in the area occasionally and are unlikely to depend on the site.

13.8.85 During baseline surveys the presence of an egrety resulted in concerns about the potential for the construction of the Residential Development to form a barrier to egret flight lines. To address this potential impact a design decision was made to relocate the development to minimise intersection with observed flightlines. In addition the construction of a potential alternative egretry is proposed within the WNR. Recently the egretry has been abandoned and whilst there is little prospect of it becoming re-established it has been decided to retain these mitigation measures.

13.8.86 Fragmentation caused by the erection of site fencing is not expected to cause a significant impact to Species of Conservation of Importance recorded within the site, although it could restrict the movement of species such as Eurasian Otter and Crab-eating Mongoose which, whilst not recorded within the Assessment Area, might be expected to be present.

13.8.87 Options 1A and 1B are similar in many respects, the slight difference between these two options arising from the larger number of buildings in Option 1B. The gaps between buildings will be smaller in this option creating a slightly greater blockage of sightlines for birds. It is predicted, therefore, that Option 1B will result in slightly greater habitat fragmentation than Option 1A. It is emphasised that the difference between these options is slight, particularly in light of the abandonment of the egretry, as it was the potential blockage of flights to and from this feature that was the principal source of concern with respect to habitat fragmentation.

13.9 Mitigation Measures

13.9.1 In Section 13.8 five main categories of potential ecological impacts were identified on habitats and Species of Conservation Importance: • Temporary habitat loss resulting from construction phase disturbance (particularly noise and

vibration). • Permanent habitat loss associated with the construction of the residential development. In

addition disturbance associated with the operation of the site is expected create an area around the development within which density of sensitive species (primarily birds) will be permanently reduced.

• Habitat fragmentation arising from the construction of the residential development and erection of fencing.

• Pollution events arising from construction activities. • Pollution events arising from sewerage leaks during site operation.

13.9.2 Of these the permanent habitat loss associated the construction and operation of the residential development is the most significant because it will potentially have a high impact on habitats of high conservation value (aquaculture ponds) and Species of Conservation Importance (including the globally important species Black-faced Spoonbill). Mitigation of Construction Phase Habitat Loss and Disturbance

13.9.3 The key strategy for mitigating permanent and temporary habitat loss arising from the construction of the Residential Development is the construction and appropriate management of a Wetland Nature Reserve (WNR) within that component of the site (approximately 76.1 ha) not occupied by the proposed residential development. The aim of the WNR is to compensate permanent habitat loss and to mitigate disturbance effects through the creation of approximately 14.4 ha. of freshwater marsh habitat. In addition approximately 61.7 ha of remaining fishponds will be enhanced and managed to increase their carrying capacity for bird Species of Conservation Importance.

13.9.4 The strategy for constructing the WNR has been carefully considered and incorporates the following (strategic) elements: • Advance construction. Construction works associated with the WNR will be completed in

advance of the commencement of construction at the Residential Development – this


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minimises concurrent disturbance associated with construction works in these two areas. • Staged construction. The construction of the WNR will be staged to minimise the areas

affected at any one time. This minimises disturbance effects and ensures that there is always sufficient habitat for birds, and other species, considered to be of Conservation Importance within Fung Lok Wai.

• Interim management. To ensure that carrying capacity of areas unaffected by construction at any one time are sufficient to maintain populations of bird (and other) Species of Conservation Importance, interim management will be undertaken during WNR and Residential Development construction phases.

• Long-term management. Once construction works are completed and the Residential Development enters its operational phase, long-term management within the WNR will commence.

13.9.5 The construction programme for the WNR and Residential Development is indicated in Figure 13-13. The timeframe for these works has been divided into series of Phases, including: • Pre-construction Phases I-VI – when WNR works and proposed Development Area site

clearance and forming will be undertaken. • Construction Phase – when work on the Residential Development foundations and

superstructure will take place. • Operation Phase – when the Residential Development is occupied and the WNR enters long-

term management.

13.9.6 The activities involved in each stage are briefly described below (dates shown are indicative). Pre-Construction Phase I (Jul ‘10– Sep ‘10)

13.9.7 During this phase the developer will take occupation of the site and make preliminary preparations including erection of site fencing. No specific habitat management is envisaged at this stage and all ponds will remain under their current aquaculture regime. All ponds will potentially be available as habitat that is no ponds will be directly affected by construction activities. Pre-Construction Phase II (Oct ’10 – Mar ’11)

13.9.8 During this phase pond enhancement works will commence. Enhancement is aimed at improving the quality of ponds as waterbird habitat (as described more fully in Section 14) and involves re-profiling and enlarging the ponds. To minimise disturbance and to maximise the extent of available habitat these works will be undertaken progressively within Sector 1. The works involved in enhancement include the draining of adjacent ponds and the excavation of the intervening bund. This will be done according to the construction plan of the Wetland Nature Reserve (see Section 14). These works are similar to normal pond management activities and are not in themselves expected to cause undue disturbance to birds, nevertheless to minimise potential disturbance impacts, pond enhancement works will be phased.

13.9.9 The maximum area of pond affected by these enhancement activities during this Phase will be 4.2 ha (representing the largest ponds that will be concurrently drained and re-profiled). Prior to, and following enhancement works, the ponds will be filled with water and are considered to be available as habitat for birds and other Species of Conservation Importance.

13.9.10 During these works the ponds located within Sectors 2 and 3, the area proposed for marshland (14.4 ha) and development area (4.0 ha) will remain under their existing management regime ensuring that, throughout this Phase, at least 76.0 ha of pond will remain as available. Pre-Construction Phase III (Apr ’11 – Sep ’11)

13.9.11 During this Phase enhancement works will commence in Sector 2 and site clearance will commence in the Development Area. The enhancement works in Sector 2 will follow the same pattern as described above, however, the maximum area affected at any one time will be slightly larger at approximately 6.1 ha. Once the Development Area clearance is complete a further, approximately, 4.0 ha of pond habitat will become unavailable. During this Phase, therefore, the minimum pond area available as habitat will be approximately 70.0 ha.


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13.9.12 To compensate for this reduction in habitat area it is proposed to commence interim management in the Sector 1 ponds (all of which were enhanced in Phase II). The interim management strategy is to increase the carrying capacity of ponds by drawing them down for longer periods than is normal under traditional management and to artificially increase the availability of prey species for wetland birds through stocking of trash fish species. The key elements of the interim management plan include: • Management of water quality, specifically pH to ensure appropriate conditions for fish

survival. Although trash fish species are relatively hardy compared to many commercial fish, they can be affected by low pH conditions. If pH drops below 4.5 then peanut residue will be added to raise pH;

• Rotational, partial drain down of pair ponds. Once drained down each pair of ponds will be maintained with shallow water < 30 cm deep for a period of 4 weeks;

• Stocking of trash fish as required to ensure that target carrying capacities are met; and, • Minimising human presence to limit disturbance. Pre-Construction Phase IV (Oct ’11 – Mar ’12)

13.9.13 Interim management will continue at Sector 1 (20.4 ha) and commence at Sector 2 ponds (21.3 ha). In addition interim management will also be implemented in Sector 3 ponds (20.1 ha, although these are yet to be enhanced). No pond enhancement works will be undertaken during this Phase. Creation works will commence within the marshland area, while site clearance continues in the development area, making approximately 14.4 ha and 4.0 ha, of pond area unavailable, respectively. Consequently a minimum of 61.8 ha of pond area will be available, all of which will be under interim management.

13.9.14 During this phase the physical activities associated with marsh creation works will be completed with planting taking place in the following Phase. Pre-Construction Phase V (Apr ’12 – Sep ’12)

13.9.15 Interim management will continue at Sector 1 (20.4 ha) and 2 ponds (21.3 ha). Ponds in Sector 3 will undergo enhancement occupying a maximum of 3.82 ha at any one time while the remaining 16.2 ha of pond area will be kept under interim management. Planting of marshland habitats will take place followed by approximately 12 months of establishment. For the purposes of this assessment it is assumed during this period that all the marshland habitat (14.4 ha) will be unavailable as habitat (although it is actually likely that some species will begin to make use of it). Site clearance and preparation works will continue in the development area (4.0 ha). Thus a minimum of 58.0 ha of pond area will be available, all of which will be under interim management. Pre-Construction Phase VI (Oct ’12 – Jun ’13)

13.9.16 Marsh establishment will continue (and hence assumed to be unavailable). Interim management will continue at Sector 1 (20.4 ha), 2 (21.3 ha) and 3 ponds (20.06 ha) resulting in a total area of available pond area of 61.8 ha, all of which is under interim management. Construction Phase (Jul ’13 – Sep ’16)

13.9.17 Construction works are programmed to commence in July 2013. During this phase all pond enhancement works will be completed and a total area of 61.8 ha of ponds will be under interim management in Sectors 1, 2 and 3. Marsh establishment is expected to be substantially complete (although maturation will continue over several additional years). Consequently there will be an additional 14.4 ha of marshland habitat available.

13.9.18 The commencement of construction works will result, however, in the generation of substantially higher levels of noise and vibration and hence disturbance than was experienced during Pre-Construction Phases. It is assumed, therefore, that sections of wetland habitat adjacent to the construction area will be functionally unavailable to species that are sensitive to disturbance. The extent of these areas was assessed in Section 13.8 and are summarised in Figure 13-12 and Table 13-55.

13.9.19 The key strategy for mitigating these disturbance effects is to maintain interim management in all of the enhanced Sector 1, 2 and 3 ponds. It is anticipated that interim management will increase


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the carrying capacity of these ponds sufficiently to off-set temporary functional habitat loss associated with the displacement of birds from areas affected by construction phase disturbance.

13.9.20 The objective, therefore, during this Phase is to provide habitat of sufficient quality to maintain the numbers of birds observed during the baseline. To gain an indication of the existing carrying capacity of the Fung Lok Wai wetlands, the survey data obtained during the baseline survey were analysed to identify the maximum number of birds recorded. These data were then converted to densities by dividing the maximum number of individuals observed within the within the Study Site by the extent of wetland in the Study Site (approximately 80.1 ha). The Study Site sits within a larger area of wetland habitat, for comparison this table also shows the maximum and mean number of individuals of Species of Conservation Importance observed within the total Assessment Area. These are also shown as densities achieved by dividing the counts by the extent of wetland within the Assessment Area (approximately 170.6 ha of wetland). These data are shown in Table 13-59.

Table 13-59 Observed maximum, mean (counts and densities) of wetland bird species using the wetland in the Study Site and Assessment Area during 2001

Mean and maximum counts and densities (individuals per ha of wetland habitat) of sensitive species using the wetland in the Study Site and Assessment Area during baseline surveys Study site Assessment area Max Mean Max Mean

Species

Count Density Count Density Count Density Count Density Black-faced Spoonbill 38 0.47 2.77 0.03 39 0.23 4.53 0.03 Greater Spotted Eagle 0 - - - 2 N/A N/A N/A Imperial Eagle 1 N/A N/A N/A 1 N/A N/A N/A Red-billed Starling 12 0.15 1.10 0.01 182 1.07 24.67 0.15 Common Teal 3 0.04 0.20 <0.01 643 3.77 35.47 0.21 Eurasian Wigeon 11 0.14 1.47 0.02 74 0.43 7.73 0.05 Osprey 0 - - - 3 N/A N/A N/A Black Kite 18 0.22 1.90 0.02 29 0.17 10.37 0.06 Chinese Pond Heron 42 0.52 11.17 0.14 80 0.47 13.00 0.08 Great Cormorant 24 0.30 4.60 0.06 92 0.54 13.20 0.08 Great Egret 128 1.60 20.87 0.26 132 0.77 24.50 0.14 Little Egret 480 5.99 59.53 0.74 506 2.97 122.73 0.72 Black-crowned Night Heron 40 0.50 6.60 0.08 46 0.27 9.60 0.06 Cattle Egret 68 0.85 16.80 0.21 72 0.42 29.83 0.18 Grey Heron 67 0.84 13.27 0.17 151 1.89 41.73 0.25 Striated Heron 3 0.04 0.37 <0.01 7 0.09 1.03 0.01 Collared Crow 10 0.12 1.10 0.01 18 0.11 8.50 0.05 Crested Serpent Eagle 0 - - - 1 N/A N/A N/A Little Grebe 12 0.15 4.17 0.05 42 0.25 21.27 0.13 Little Ringed Plover 30 0.37 2.57 0.03 38 0.22 8.87 0.05 Pied Kingfisher 2 0.02 0.17 <0.01 6 0.04 1.30 0.01 Temminck’s Stint 9 0.11 0.37 <0.01 20 0.12 3.13 0.02 White-throated Kingfisher 6 0.07 1.57 0.02 15 0.09 3.47 0.02 Wood Sandpiper 3 0.04 0.30 <0.01 12 0.07 2.17 0.01


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N/A - Indicates that whilst this species was observed during surveys it was seen only in flight over Fung Lok Wai in very low numbers. It was not appropriate to calculate densities for these species

13.9.21 To understand the magnitude of increase of carrying capacity required under the interim management regime the extent of habitat loss has been estimated by calculating the proportion of habitat lost through construction and disturbance during the construction phase (see Table 13-60). For these calculations it is assumed that the marsh area is unavailable (hence permanent habitat loss is shown as 18.4 ha, equivalent to the development area, 4.0 ha, and the constructed marsh habitat, 14.4 combined). In practice it is actually assumed that the marsh will be sufficiently mature during this Phase to provide habitat for some of Species of Conservation Importance. Habitat loss is calculated on the basis of the reduced density distances shown in Table 13-56.

Table 13-60 Extent and proportion of direct and indirect (due to disturbance) habitat loss during construction for sensitive wetland bird species.

Habitat loss (ha) Extent of wetland habitat (ha) Proportion of wetland habitat affected (ha)

Species

Permanent Due to disturbance

Max area affected Study Site Assessment

Area Study Site Assessment Area

Black-faced Spoonbill 18.4 23.4 41.8 80.1 170.6 52% 24%

Greater Spotted Eagle 18.4 33.0 51.4 80.1 170.6 64% 30%

Imperial Eagle 18.4 33.0 51.4 80.1 170.6 64% 30%

Red-billed Starling 18.4 6.4 24.8 80.1 170.6 31% 15%

Common Teal 18.4 12.0 30.4 80.1 170.6 38% 18%

Eurasian Wigeon 18.4 12.0 30.4 80.1 170.6 38% 18%

Osprey 18.4 33.0 51.4 80.1 170.6 64% 30%

Black Kite 18.4 2.0 20.4 80.1 170.6 25% 12%

Chinese Pond Heron 18.4 12.0 30.4 80.1 170.6 38% 18%

Great Cormorant 18.4 23.4 41.8 80.1 170.6 52% 24%

Great Egret 18.4 23.4 41.8 80.1 170.6 52% 24%

Little Egret 18.4 19.9 38.3 80.1 170.6 48% 22%

Black-crowned Night Heron 18.4 2.0 20.4 80.1 170.6 25% 12%

Cattle Egret 18.4 2.0 20.4 80.1 170.6 25% 12%

Grey Heron 18.4 12.0 30.4 80.1 170.6 38% 18%

Striated Heron 18.4 12.0 30.4 80.1 170.6 38% 18%

Collared Crow 18.4 2.0 20.4 80.1 170.6 25% 12%

Crested Serpent Eagle 18.4 33.0 51.4 80.1 170.6 64% 30%

Little Grebe 18.4 6.4 24.8 80.1 170.6 31% 15%

Little Ringed Plover 18.4 6.4 24.8 80.1 170.6 31% 15%

Pied Kingfisher 18.4 2.0 20.4 80.1 170.6 25% 12%


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Temminck’s Stint 18.4 6.4 24.8 80.1 170.6 31% 15%

White-throated Kingfisher 18.4 2.0 20.4 80.1 170.6 25% 12%

Wood Sandpiper 18.4 6.4 24.8 80.1 170.6 31% 15%

13.9.22 It can be seen from Table 13-60 that the extent of habitat loss within the study site for the wetland species during construction varies between 25% (for disturbance tolerant species such as Cattle Egret) and 64% for Greater Spotted Eagle, Imperial Eagle, Osprey and Crested Serpent Eagle. These species were observed infrequently, over-head and consequently the reliance of these raptors on Fung Lok Wai is considered low and that the mitigation proposed below for sensitive waterbirds will adequately safeguard habitat for this species, particularly in light of the wider availability of suitable habitat for these species in the North-west New Territories.

13.9.23 The most important conclusion from Table 13-60, therefore, is that, habitat availability within the Study Site for the most sensitive waterbirds (Black-faced Spoonbill, Great Cormorant and Great Egret) will be approximately halved during the construction phase.

13.9.24 It should be noted that the figures presented in Table 13-60 are highly conservative, they are based on construction activity occurring within the whole of the development area simultaneously, which is unlikely to occur. Rather, construction is expected to proceed in stages with disturbance limited to specific areas of the development area and a significantly smaller area of surrounding wetland. As mentioned above it is also assumed that the constructed marsh does not contribute to available habitat, although in practice it is likely to support some Species of Conservation Importance. It can also be seen from Table 13-60 that when the availability of wetland habitat in neighbouring areas (taken as wetland habitat present in the Assessment Area ie Study Site plus 500m buffer) is taken into consideration the extent of habitat loss is significantly less due to the greater availability of habitat within this larger area.

13.9.25 To mitigate the impact of direct habitat loss and disturbance effects, temporary management will be required to increase the carrying capacity within remaining habitat. This management will take place on-site (ie within the Study Site). The mitigation targets for key bird Species of Conservation Importance are indicated in Table 13-61 This table shows the increase in the population required to mitigate habitat loss and temporary disturbance effects during the construction phase. Using the results of the baseline surveys the densities (ie birds per hectare of wetland) implied by these mitigation targets are shown. Species with low target densities (including Greater Spotted Eagle, Imperial Eagle, Osprey and Crested Serpent Eagle which recorded very infrequently and have a limited dependence on the site) have not been included in this table. It should be noted that these targets are intended as a reference point to inform the implementation and evaluation of mitigation, which will need to be undertaken using an adaptive management approach.

13.9.26 Targets are shown only for key species in Table 13-61. These species have been selected because they are considered to be the most sensitive and abundant waterbird species and hence most susceptible to impacts arising from habitat loss and disturbance. It is expected that habitat management undertaken to achieve the mitigation targets defined for these species will be more than sufficient to mitigate impacts on other species that are less sensitive to disturbance and which occur in lower numbers.

Table 13-61 Mitigation targets for key wetland bird species of conservation importance within remaining wetland areas of the Study Site required to fully compensate for habitat loss and disturbance impacts during construction

Species Mitigation target (species population

increase)

Implied target densities (birds/ha) using existing

baseline data1 Black-faced Spoonbill Double 0.07 Chinese Pond Heron Increase by 61% 0.22


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Great Cormorant2 Double 0.12 Great Egret Double 0.54 Grey Heron Increase by 61% 0.27 Little Egret Increase by 92% 1.41 Cattle Egret Increase by 33% 0.28

Notes: 1 The figures included for reference only. The actual mechanism for identifying specific population targets is to be agreed with AFCD prior to the commencement of the construction. 2 If Great Cormorant numbers exceed mitigation targets it may be necessary to implement controls on the size of the population. The implementation of such controls will be determined in the context of the Adaptive Management framework and in discussion with AFCD

13.9.27 In practice, because the populations of these species will fluctuate within the North-west New Territories due to a range of external factors beyond the developers control, the targets densities will be calculated using information obtained from control site locations. These control sites will be established in appropriate locations to be agreed with AFCD prior to the construction of the proposed development. Appropriate locations would include places that are known to support similar communities and populations of birds to those found at Fung Lok Wai. As such, Lut Chau and Nam Sang Wai are the suggested potential control sites. The actual locations of the control sites would be confirmed prior to the construction of the proposed development.

13.9.28 The magnitude of the increase in carrying capacity required is considered to be achievable on a temporary basis because: • Existing densities (particularly mean densities) are considered to be low for most of the

species listed (see Table 13-59), which provides considerable scope for increasing the carrying capacity of ponds within the Study Site through management.

• Reference to recent monitoring reports from monitoring associated with KCRC East Rail extensions at Lok Ma Chau (AEC 2003, 2004, 2006a, 2006b) indicate that the densities implied for key species (Black-faced Spoonbill, Great Cormorant and Great Egret) are readily achievable (and have been frequently exceeded).

• Although monitoring at Lok Ma Chau has indicated that numbers of Little Egret and Chinese Pond Heron have tended to fall short of their target numbers for that site (AEC 2006a), the actual densities achieved, particularly for Chinese Pond Heron have often exceeded the specific mitigation target densities at Fung Lok Wai for both construction and operational phases. With respect to Little Egret densities achieved have, in the past, been lower than construction phase mitigation targets at Fung Lok Wai. Within the adaptive management programme for Lok Ma Chau, however, various management actions have been identified to increase numbers and these have had positive results for Little Egret (AEC 2006a). AEC (2006b) further indicates that a density of 2.45 birds/ha has been achieved in Aug-Dec 2005, a considerably higher density than that required to fully compensate construction phase disturbance effects at Fung Lok Wai. The results of monitoring at Lok Ma Chau, and the management required to achieve targets, will continue to be reviewed. Relevant lessons from Lok Ma Chau will be incorporated, where appropriate, within the adaptive management programme for the WNR at Fung Lok Wai.

13.9.29 Under traditional management the production of non-commercial by-product, including prawns and fish, such as Tilapia, that are below marketable weight is in the order of 260 kg/ha/year (See Section 12.4, Aspinwall 1997 and Primavera, 2000). To achieve the mitigation targets the availability of small fish and prawns will need to be increased to provide enhanced feeding opportunities. Experience from the implementation of a similar approach by KCRC at Lok Ma Chau indicates that optimal stocking densities are likely to be in the range 2-5 times the expected ‘normal’ biomass of trash fish, ie up to 1,300 kg/ha/year. Imported fish will comprise small Tilapia (target weight approximately 50g / individual). A key reason for the relatively large increase in stocking density is due to the fact increased prey availability benefits a wide variety of piscivorous birds, including cormorants and ardeids, all of which can be expected to increase in numbers within the mitigation area.

13.9.30 The experience at Lok Ma Chau (eg AEC 2006a, 2006b) also indicates that a flexible (adaptive management) approach is required. The effectiveness of mitigation requires careful attention to


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water quality, adjustment to stocking densities, periodic review of the timing and duration of draw-down and continuous monitoring.

13.9.31 Not of all of the Species of Conservation Importance recorded within or close to the Study Site are piscivorous birds. It is expected, however, that the programme of pond enhancement and interim management proposed during pre-construction and construction phases will also benefit these species.

13.9.32 Red-billed Starling and Collared Crow tend to be closely associated with bund habitats and adjacent agricultural land-uses. Whilst some bunds will be removed during pond enhancement a substantial proportion will remain intact, sufficient to maintain the low observed densities of these birds. Staging the enhancement works will ensure that the area disturbed during enhancement of the fishponds and the construction of the marsh habitats will be limited.

13.9.33 With respect to raptors, it is considered that the actions taken to maintain waterbird densities during the construction phase, including stocking of ponds with fish species, will off-set potential disturbance effects. The maintenance of waterbird numbers will benefit those species that forage on these (Greater Spotted Eagle and Imperial Eagle) and stocking of fish species will benefit Osprey which is piscivorous. Black Kite is an opportunistic scavenger utilising a wide range of habitats. It is highly tolerant of human presence and is expected to continue to forage within the pond enhancement areas

13.9.34 Waterfowl (Common Teal and Eurasian Wigeon) will forage on vegetation and other food items found at the margins of ponds. It is expected that these species will continue to utilise ponds during the construction phase. If any individuals are displaced from the Study Site due to disturbance it is anticipated that there will be abundant ponds in adjacent areas (ie within the Buffer Zone to the Study Site) to accommodate these birds.

13.9.35 Waders (Little Ringed Plover, Temminck’s Stint and Wood Sandpiper) will forage on invertebrates associated with pond margins, the creation of additional shallows and lengthening of draw-down periods is expected to significantly benefit these species.

13.9.36 Few non-avian Species of Conservation Importance were considered likely to be directly dependent on the ponds within the Study Site, although some reptile species are expected to occur including:

13.9.37 Common Rat Snake (Ptyas mucosus) and Indo-Chinese Rat Snake (Ptyas korros) – are both likely to be found in varied habitats including agricultural areas, shrub land, banks of streams, around aquaculture ponds and reservoirs. Mangrove Water Snake (Enhydris bennettii) is typically found in muddy coastal habitats, although in the baseline surveys for this study it was recorded only once but near fish ponds. It is expected that the staged approach to the enhancement of the ponds and constructed marsh areas within the WNR will ensure that sufficient habitat remains for these species throughout the construction phase.

13.9.38 Banded Krait (Bungarus fasciatus) and Many-banded Krait (B. multicinctus) have little reliance on fishpond habitats are not expected to be adversely affected by construction works. Mitigation of Operational Phase Habitat Loss and Disturbance

13.9.39 The disturbance generated during operational phase (ie once the Residential Development is occupied and all construction works have ceased) is considered to be significantly lower than during the construction phase.

13.9.40 Table 13-62 indicates the extent and proportion of direct and indirect (due to disturbance) habitat loss during operation. Habitat low is calculated on the basis of the reduced dernsity distances shown in Table 13-53.

Table 13-62 Extent and proportion of direct and indirect (due to disturbance) habitat loss during operation for wetland bird species

Species Habitat loss (ha) Extent of wetland habitat (ha)

Proportion of wetland habitat affected (ha)


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Permanent Due to disturbance

Max area affected

Study Site Assessment Area Study Site Assessment

Area

Black-faced Spoonbill 18.4 6.4 24.8 80.1 170.6 31% 15%

Greater Spotted Eagle 18.4 33.0 51.4 80.1 170.6 64% 30%

Imperial Eagle 18.4 33.0 51.4 80.1 170.6 64% 30% Red-billed Starling 18.4 2.0 20.4 80.1 170.6 25% 12% Common Teal 18.4 2.0 20.4 80.1 170.6 25% 12% Eurasian Wigeon 18.4 2.0 20.4 80.1 170.6 25% 12% Osprey 18.4 33.0 51.4 80.1 170.6 64% 30% Black Kite 18.4 0.8 19.1 80.1 170.6 24% 11% Chinese Pond Heron 18.4 0.8 19.1 80.1 170.6 24% 11%

Great Cormorant 18.4 4.5 22.9 80.1 170.6 29% 13% Great Egret 18.4 6.4 24.8 80.1 170.6 31% 15% Little Egret 18.4 1.8 20.2 80.1 170.6 25% 12% Black-crowned Night Heron 18.4 0.8 19.1 80.1 170.6 24% 11%

Cattle Egret 18.4 0.8 19.1 80.1 170.6 24% 11% Grey Heron 18.4 0.8 19.1 80.1 170.6 24% 11% Striated Heron* 18.4 0.8 19.1 80.1 170.6 24% 11% Collared Crow 18.4 0.8 19.1 80.1 170.6 24% 11% Crested Serpent Eagle 18.4 33.0 51.4 80.1 170.6 64% 30%

Little Grebe 18.4 1.1 19.5 80.1 170.6 24% 11% Little Ringed Plover 18.4 1.1 19.5 80.1 170.6 24% 11%

Pied Kingfisher 18.4 0.8 19.1 80.1 170.6 24% 11% Temminck’s Stint 18.4 1.1 19.5 80.1 170.6 24% 11% White-throated Kingfisher 18.4 0.8 19.1 80.1 170.6 24% 11%

Wood Sandpiper 18.4 1.1 19.5 80.1 170.6 24% 11%

* Habitat loss for Striated Heron will be over-estimated here because this is a species primarily of mangroves and inter-tidal habitats (although it was also recorded in small numbers within the study site)

13.9.41 As for the construction phase the largest exclusion areas predicted are for four raptor species that are considered to have a low dependence on the site. It is assumed that the mitigation proposed for this phase for waterbirds will be more than adequate to compensate habitat loss for these species.

13.9.42 The most important conclusion from Table 13-62, therefore, is that, habitat availability within the Study Site for the most sensitive waterbirds (Black-faced Spoonbill, Great Cormorant and Great Egret) will be reduced by approximately 30% during the operation phase.

13.9.43 It is anticipated that sympathetic long-term management of the WNR will be more than sufficient to mitigate permanent habitat loss and ongoing disturbance caused by operation of the Residential Development. As a precaution it is assumed that the constructed marsh habitat within the WNR will be unavailable (although in practice it is expected to be fully established after several years). Consequently mitigation has been approached on the basis that mitigation targets will be achieved through enhancement of the carrying capacity of those fishponds unaffected by disturbance effects. The managed carrying capacities required within these fishponds are indicated in Table 13-63. Species with low target densities (including Greater Spotted Eagle, Imperial Eagle, Osprey and Crested Serpent Eagle which were recorded very infrequently and have a limited dependence on the site) have not been included in this table. It is considered that the establishment of the WNR will provide, in the long-term, enhanced and secure foraging opportunities for Greater


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Spotted Eagle, Imperial Eagle and Crested Serpent Eagle and that this will off-set any impacts arising from habitat loss and disturbance due to the construction and operation of either Option 1A or 1B. The area of fish ponds within the WNR will be less than that which currently exists (as approximately 14.4 ha will be converted into freshwater marsh habitats), although those fishponds retained will be enhanced through enlargement and more sympathetic management. Nevertheless, it is considered that there will be a slight reduction in the extent of foraging habitat available for Osprey, although this loss is not considered to be significant in light of the low reliance that this species has on the existing habitats within Fung Lok Wai.

Table 13-63 Mitigation targets for wetland bird species of conservation importance within remaining wetland areas of the Study Site required to fully compensate for habitat loss and disturbance impacts during operation

Species Mitigation target (species population

increase)1

Implied target densities (birds/ha) using existing

baseline data2 Black-faced Spoonbill Increase by 45% 0.05 Chinese Pond Heron Increase by 32% 0.18 Great Cormorant3 Increase by 41% 0.08 Great Egret Increase by 45% 0.37 Grey Heron Increase by 32% 0.22 Little Egret Increase by 33% 0.98 Cattle Egret Increase by 32% 0.27

Notes: 1 For these calculations it is assumed that mitigation will be achieved only through

management to increase the carrying capacity of those fishponds unaffected by operational disturbance 2 The figures included for reference only. The actual mechanism for identifying specific population targets is to be agreed with AFCD prior to the commencement of construction. 3 If Great Cormorant numbers exceed mitigation targets it may be necessary to implement controls on the size of the population. The implementation of such controls will be determined in the context of the Adaptive Management framework and in discussion with AFCD

13.9.44 The key strategy for compensating the functional loss of wetland arising from the ongoing operation of the residential development is the appropriate management of the WNR.

13.9.45 A detailed draft Habitat Creation and Management Plan for the proposed Wetland Nature Reserve (WNR) is provided in Section 14. In summary, though the WNR will comprise two key elements: • A large expanse of retained, but ecologically enhanced, fishponds; and, • An area of re-created ‘natural’ marshland.

13.9.46 Fishponds that are actively managed for commercial aquaculture in the Deep Bay area are currently full for most of the year and their use by birds is severely limited due to their relatively steep sides, deep water and their frequent lack of marginal vegetation. These characteristics also limit their use by other species and hence fishponds tend to have relatively low biodiversity compared to many wetland habitats.

13.9.47 The management of fishponds for commercial aquaculture, however, creates a key by-product in the form of abundant “trash fish” – small, non-commercial fish and invertebrates. When ponds are drained down during the winter months for harvesting, large concentrations of birds can be observed foraging in the shallow water for trash fish. As only a small proportion of fishponds are drained at any one time, and only for short periods, the spatial distribution of feeding birds is highly dynamic and variable as birds seek out ponds as they are drained. ‘Feeding bottlenecks’ may occur if there are insufficient ponds to support foraging bird populations.

13.9.48 Although much of the Assessment Area is composed of wetland habitats in the form of aquaculture ponds, poor water quality and unsympathetic pond design severely limit its value for most faunal groups. Furthermore, there is inadequate vegetation cover on the site to support


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breeding populations of most wetland birds.

13.9.49 The main objectives of enhancing fishponds are, therefore, to: • Increase the value of fishponds to herons and egrets outside harvesting periods (i.e. draw-

down), by increasing food resources and food availability and by reducing disturbance effects. Enhancement of the value of fishponds to such birds outside harvest periods could reduce the potential for ‘feeding bottlenecks’ thereby possibly reducing the area of fishponds needed to support the population.

• Increase their overall biodiversity value and suitability for non-piscivorous bird Species of Conservation Importance, non-bird Species of Conservation Importance (e.g. snakes), and other species such as some mammals (e.g. Eurasian Otter), amphibians and reptiles, whilst maintaining their current important functions for herons, egrets and other water birds.

13.9.50 The enhanced fishponds will be located away from the development area to minimise disturbance impacts. They will also be contiguous with the main area of fishponds in the WCA and Ramsar site as a whole. Maintaining a contiguous area for compensation, which is linked, with an existing area of recognised conservation importance is of significant ecological value.

13.9.51 The natural wetland area will consist of a marshland complex, including areas of shallow open mesotrophic water (i.e. of moderate nutrient status), with adjoining reedbeds and other emergent vegetation, shallow margins, islands, irregular shorelines, and an area of seasonally inundated grazed marsh and pools. Such fresh water marshes are a scare habitat in Hong Kong and would develop rich and abundant aquatic and emergent plant communities. This in turn may support rich invertebrate, amphibian and reptile communities.

13.9.52 There are three key features of this proposed layout: • The majority of the fishponds on the site are maintained, including all those within the Mai

Po Inner Deep Bay Ramsar site boundary. This avoids the loss or detrimental modification of any wetland area within the Ramsar site and maintains the large open contiguous block of fishpond habitat in the area.

• The location of the proposed area for the re-creation of natural wetlands will maximise the potential for ecological links with the following complementary adjacent habitats: o scrub and woodland habitats on the hillsides to the south of the site; o inter-tidal mangrove habitats along the former Tai River outfall; and, o the wetland creation at Hong Kong Wetland Park (HKWP). o These habitats may provide sources for the natural spread and establishment of some

plants and animals within the wetland area. In addition they will provide additional shelter, food or breeding sites for wetland species and ecological ‘corridors’, which may facilitate dispersal.

• As the re-created wetland will contain abundant tall reedbeds, as well as other tall wetland vegetation and scattered trees, this will serve as a buffer between the residential development and the fishponds. This will reduce disturbance of birds feeding within the fishponds.

13.9.53 The specific aquaculture pond habitat targets for the mitigation area are indicated in Table 13-64.

Table 13-64 Mitigation Targets for Enhanced Aquaculture Ponds

Mitigation issue Target

Enhancement of aquaculture pond area 61.7 ha. (Including, control structures and alternative egretry)

Shallow fish pond area (i.e. < 10cm depth) More than 20% (excluding aquaculture ponds that are dry for maintenance)

Cover of undesirable invasive species and exotic species

Less than 10% of vegetation cover

Plant cover on aquaculture pond bunds and islands

Vegetation of height >10cm to comprise less than 5% plant cover on more than 75% of the area of aquaculture pond bunds and islands


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Area under traditional polyculture fish pond management systems

70-90% of the aquaculture pond area (Excluding aquaculture ponds that are dry for maintenance)

Area set-aside from fish farming and under specific conservation management

10 - 30% of the aquaculture pond area (Excluding aquaculture ponds that are dry for maintenance)

13.9.54 Planting of trees on bunds will be avoided where such planting would interfere with bird flightlines. In addition continuous planting that would enclose or overshadow fishpond or freshwater marsh habitats will also be avoided. To improve foraging opportunities for some bird species (notably passerines such as Red-billed Starling) fruit-bearing trees, including, for example, China-berry (Melia azedarach) will be planted in small clumps.

13.9.55 The specific targets for the Marsh Habitat mitigation area are indicated in Table 13-65.

Table 13-65 Mitigation Targets for Marsh Habitat

Mitigation issue Target

Creation and maintenance of a total of marshland habitat in Favourable Condition

14.4 ha. (including essential structures, e.g. water control structures) Freshwater marsh habitats are defined as areas where wetland hydrological conditions, or wetland soils are present or where wetland plants are dominant, with shallow water (average < 1m) and wetland plant species cover greater than 30% of the area.

Cover of wetland plant species More than 90% established vegetation (excluding open water marsh area)

Cover of undesirable invasive species and exotic species

Less than 10% of vegetation cover

The average depth of water 30 – 50 cm (outside drawn down periods for maintenance)

Area of open water (i.e. unvegetated water)

20-30%.

13.9.56 As the Marsh Habitat will be new habitat there are no existing animal populations associated with marsh habitats upon which to base mitigation targets. In addition it is anticipated that the Marsh Habitat will be subject to disturbance arising during the operation phase due its proximity to the residential development. Nevertheless there are a range of bird species that would be expected to use the Marsh Habitat. Management of the marsh habitats will focus on ensuring that that these “primary” species (see Table 13-66) are present. In addition there are a range of other species that are associated with marsh habitats. Whilst it is desirable that these species are present, they will not form the primary focus of management effort. In addition it is expected that the marsh habitat will support a range of amphibian, reptile and invertebrate species.

Table 13-66 Bird SpeciesExpected to Use the Marsh Habitat

Primary Species (Presence expected)

Secondary Species (Presence desirable)

Birds Little Egret (R) Chinese Pond Heron (R) Great Egret (W) Grey Heron (W)

Japanese Quail (P / W) Eurasian Coot (W) Pheasant-tailed Jacana (P) Greater Painted Snipe (R)


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Eurasian Teal (W) Black-winged Stilt (W) Pintail / Swinhoe’s Snipe (P / W) Common Snipe (W) Zitting Cisticola (W)

Black-winged Stilt (B) Richard’s Pipit (P / W) Bluethroat (P / W) Pallas’s Grasshopper Warbler (P)

Key: R – resident; W – winter; P – passage; B - breeding

Residual Disturbance during Operation of Wetland Nature Reserve

13.9.57 Lockable gates will also be placed on vehicle access points to the site. A 2 m high wall between the development area and the wetland will also prevent direct access except via the designated footpaths.

13.9.58 Fish farming activities within the Wetland Nature Reserve are also a potential source of disturbance within the fishpond areas. These will therefore be reviewed, as part of the development of a management plan for the site, and modified where possible to avoid disturbance impacts.

13.9.59 Human activities along the margins of the site, such as walking along tracks and roads and aquaculture activities on adjacent fishponds may also cause significant disturbance. These would be reduced to acceptable levels by: • Provision of a 2 m high wall between the residential development and wetland area, which

itself would be screened from the wetland by tall trees (c. 10 m high); • Screening on the perimeter bunds (in aquaculture ponds) through tree and shrub

establishment; • Additional screening in the wetland itself and on the margins of open water through planting

and establishment of wetland species of tree and shrub, bamboo and reed; and, • Incorporation of design features such as islands, promontories and inlets of emergent

vegetation to provide further security and areas free of disturbance for birds.

13.9.60 Screening of the wetland will, however, be avoided where possible in order to provide clear flight lines and views across to existing surrounding fishponds and hence maintain connection with the wider Deep Bay area.

13.9.61 The long-term management of the WNR is expected to provide benefit to other species in addition to birds. The wider range of habitats that will present within the WNR, particularly with respect to the constructed marsh area is expected to provide improved habitat (over baseline conditions) for species such as: • Dragonflies. • Amphibians, including, for example: Two-striped Grass Frog (Rana taipehensis). • Reptiles, including, for example: Common Rat Snake (Ptyas mucosus) and Indo-Chinese Rat

Snake (Ptyas korros).

13.9.62 These species were all recorded in relatively low abundance during the baseline and it is reasonable to expect that the abundance of populations of species in these groups will increase. Mitigation for Disturbance to Egretry

13.9.63 Habitat fragmentation impacts were anticipated largely in relation to the potential obstruction of heron and egret flightlines originating from an egretry at Shing Uk Tsuen by the proposed residential development. Subsequent to the completion of the baseline surveys, the egretry has been abandoned. In the absence of an egretry it is considered unlikely that the residential development will obstruct flightlines as it is located on the periphery of the wetland area. There is no precedent in Hong Kong for the re-establishment of abandoned egretries, nevertheless several measures will be implemented that will reduce the likelihood that flightlines will be obstructed in the event that herons and egrets resume breeding at Shing Uk Tsuen.

13.9.64 A decision has been made, for example, to relocate the proposed development area. Following relocation the development area is, at its closest point, situated approximately 200m from the


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previous location of the egretry.

13.9.65 The factors influencing choice of egretry location are not clearly understood. The literature review of the impacts of developments on egretries undertaken as part of the impact assessment process for this site (AEC 2002) indicates some degree of tolerance to existing built structures. Investigations of other egretries located within Hong Kong e.g. the Tai Po Market, indicate that the species nesting therein can tolerate disturbance and adapt to modifications to the existing landscape, although the extent of this tolerance has yet to be quantified.

13.9.66 Whilst no specific information is available on the direct impacts of construction close to egretries, a buffer zone of 200m is considered to be sufficient because: • The area immediately adjacent to the egretry is already subject to disturbance. Existing,

ongoing human activity close to the egretry, includes housing, roads, tracks, actively managed fishpond and actively managed agricultural land;

• Construction works will be phased. Construction works in the western most 200m of the Proposed Development Area being undertaken preferentially within periods of egretry inactivity (ie. September to February).

13.9.67 There are also options for reducing potential impact on birds associated with the egretry through the management of habitats within the proposed Wetland Nature Reserve (WNR). It is known, for example, that is possible to artificially create egretries through the planting of appropriate tree, shrub and tall grass species. The successful, early establishment of a potential alternative egretry location within the proposed WNR would compensate for any potential impact caused by construction and subsequent interference with flightlines.

13.9.68 The egretry occupied about 2,000 sq. m of woodland (Figure 13-8) and it is recommended that any potential alternative egretry be of approximately the same size. The literature review found that the species most commonly associated with egretries in the New Territories include Celtis sinensis, Ficus macrocarpa and Bambusa eutuldoides and it is recommended that planting focus on the establishment of mature specimens of these three species. It is proposed that the potential alternative egretry be located in the north eastern section of the Study Site which will be subject to minimal disturbance from both the construction and operational stages of the development.

13.9.69 Analysis of GIS data also indicates that, during the breeding season, Little Egret and Chinese Pond Heron are selectively foraging in ponds that have been drained. This observation supports observations made elsewhere (eg Lok Ma Chau and Mai Po) that drawn-down ponds, particularly those which are supplemented with “trash fish” stocks, are sought out by wetland species, particularly ardeids.

13.9.70 Within the proposed management plan for the WNR, therefore, ponds will be deliberately drawn down to provide foraging habitat and to direct birds away from areas that are subject to disturbance or obstruction. Mitigation for Non-disturbance Impacts Minimisation of Dust Deposition

13.9.71 Dust deposition is a potential adverse impact in all locations. Dust creation should be minimised using standard procedures, including the damping down through water spraying during periods of dry weather. Details of mitigation measures to be used for minimising dust deposition are included in the Air Quality Impact Assessment. Minimisation of Increased Sediment Load

13.9.72 The potentially increased sediment load during construction will be controlled and minimised through implementation of good site management practices such as the provision of means for the sediment to settle before discharge of the clear supernatant. During operation, sediment loads are likely to be minimal and any solids will settle in oil interceptors and sediment traps that are incorporated within the drainage system. Effective management and maintenance programmes are expected to adequately control potential impacts from this source. Minimisation of Pollution

13.9.73 Good storage practices and handling of the chemicals used during the construction period will minimise the opportunity for impact on the terrestrial and aquatic environments. Spillage impacts


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can be minimised by storing chemicals in appropriate bunkers. Regular maintenance of interceptors will maximise their efficiency in trapping chemicals before release into the environment. Soil Compaction

13.9.74 Where works is being carried out, there is potential for compaction of the ground surface. The extent of the area to be compacted for works during construction should be minimised to reduce damage to habitats. Unless immediately required as a part of the managed mitigation area or for landscape impact mitigation purposes, each area should be re-instated when the works on that area are complete, to re-establish an environment as similar as possible to the original habitat. This may require excavation, removal of compacted (and polluted) material, and replacement with suitable material for re-creation, particularly in the areas of wetland creation and along bunds (in aquaculture ponds), which are not to be used for vehicle access in the long term. Bird Strikes with Glazed Blocks

13.9.75 Collisions of birds with built structures are most frequent where buildings or structures are transparent or reflective (i.e. glass) or otherwise difficult to see (e.g. wires). If such structures are avoided then collisions are likely to be infrequent and have minor ecological significance. This issue is taken into consideration in the mitigation of landscape and visual impacts and through the design of the residential blocks and the use of non-reflective glass. Mitigation for non-bird Species

13.9.76 On the basis of the report section above, it is clear that the principal aim of the mitigation must be the provision of suitable habitats for target species, rather than the restoration of specific habitats of intrinsic value. The Study Site currently has a low diversity of habitats and non-bird taxa. However, the mitigation proposed has been designed to provide additional habitat and management for non-target species.

13.9.77 The value of the Assessment Area for Odonata is currently limited because of the lack of high quality habitat in the form of fast running freshwater streams and undisturbed marshy areas. With appropriate management however, it is likely that the wetland habitats of the site could sustain a much more diverse odonate fauna and include further species of conservation concern. For example, the rare damselfly Mortonagrion hirosei will be encouraged through the creation of Phragmites reedbed as part of the wetland marsh design.

13.9.78 Several ponds will not be stocked with carnivorous or omnivorous fish which predate Odonata and mayfly larvae. The depth of bunds (in aquaculture ponds) will be reprofiled to create shallow margins that slope gently down to the base of the ponds. This will encourage the establishment of floating and emergent plants which dragonfly larvae are dependent upon. Along the aquatic margin of the ponds a matrix of short and taller emergent vegetation, bare substrate comprising soft mud and marshy area will be created.

13.9.79 The enhanced ponds will include shallow gently sloping areas and deeper steeper areas. This will encourage breeding of amphibians and the lack of predatory fish in some ponds will also benefit amphibians whose larvae are also predated by fish.

13.9.80 Poor water quality and highly modified freshwater habitats severely limit the ecological value of the Assessment Area for native freshwater fish. The sole running water habitat at Fung Lok Wai comprises lowland waterways with a muddy substrate. The value of the area for freshwater fish will be significantly enhanced through design of the freshwater marsh, improvement of water quality, removal of choking aquatic weeds, planting of native species and reduction in the abundance of exotic species.

13.9.81 Mangrove Water Snake was recorded within the area of fishponds that will be enhanced as part of the proposed mitigation for the site. The bunds where this species was recorded will remain intact during the enhancement works. In addition, earthworks within this area will be undertaken during the fourth quarter to ensure that breeding individuals are not disturbed. Other reptiles will be encourage to use the site through provision of the freshwater marsh which will provide more suitable habitat with the Study Site particular for species of conservation importance only otherwise recorded within the buffer zone of the Assessment Area.

13.9.82 The fishpond areas provide foraging habitat for bat species such as Japanese Pipistrelle and


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potentially other species including Noctule. Studies have shown that a colony of 100 pipistrelles may need as much as 3km2 of habitat in which to forage (Ades 1990). The proposals for management of the fishponds and the design of the freshwater marsh will increase the diversity of habitats on site for bats and could increase the carrying capacity of the site for small invertebrates, and hence increase the value of the available foraging habitat for these species.

13.9.83 Two other mammal Species of Conservation Importance, Eurasian Otter (Lutra lutra) and Crab-eating Mongoose (Herpestes urva) were not recorded during the twelve months of survey but are known to occur within similar habitats in the Deep Bay area. These species will benefit from the extra cover provided within the freshwater marsh, a reduction in on-site disturbance as a result of the reduction in fishpond operators managing the reserve, and more stringent guidelines on sympathetic management practices. Summary of compensation levels

13.9.84 Overall levels of compensation predicted from the above proposed compensation measures for Species of Conservation Importance that were recorded during the required survey period are summarised in Table 13-67Table 13-67

Table 13-67 The Overall Levels Of Compensation Predicted From Compensation Measures For Species Of Conservation Importance That Were Recorded During The Baseline Surveys At Fung Lok Wai

Species Sensitivity to disturbance COMPENSATION ACHIEVED

Birds Globally Threatened Species Black-faced Spoonbill High Feeding habitat fully compensated and

provided over a longer period; additional secure roosting habitat provided

Greater Spotted Eagle* Very High Habitat maintained, enhanced and secured in the long-term Minor level of habitat fragmentation arising from reduction in sightlines, however, this impact is not considered to be significant in light of the low reliance of this species on this habitat and the availability of suitable habitat elsewhere within Hong Kong

Imperial Eagle* Very High Habitat maintained, enhanced and secured in the long-term Minor level of habitat fragmentation arising from reduction in sightlines, however, this impact is not considered to be significant in light of the low reliance of this species on this habitat and the availability of suitable habitat elsewhere within Hong Kong

Red-billed Starling Moderate Habitat maintained and secured in the long-term

Regionally Important Species Common Teal Moderate-High Key habitat improved foraging

opportunities provided and secured in the long-term

Eurasian Wigeon Moderate-High Key habitat improved foraging opportunities provided and secured in the long-term

Osprey* Very High Partial compensation through provision of larger open areas of managed fishpond a maximum possible distance from the proposed development. Whilst there will be some loss of habitat this is not considered to be significant in light of the low reliance


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of this species on this habitat and the availability of suitable habitat elsewhere within Hong Kong

Potential Regional concern Black Kite Low Key habitat improved foraging


Chinese Pond Heron Moderate Feeding habitat fully compensated and provided over a longer period; additional loafing habitat provided; potential roosting and nesting habitat provided

Great Cormorant High Feeding habitat fully compensated; additional loafing habitat provided

Great Egret High Feeding habitat fully compensated and provided over a longer period; additional loafing habitat provided

Grey Heron Moderate Feeding habitat fully compensated and provided over a longer period; additional loafing habitat provided; potential roosting and nesting habitat provided

Little Egret Intermediate-High Feeding habitat fully compensated and provided over a longer period; additional loafing habitat provided; potential roosting and nesting habitat provided

Local conservation concern Black-crowned Night Heron Low Feeding habitat fully compensated;

additional loafing habitat provided Cattle Egret Low Feeding habitat fully compensated;

additional loafing habitat provided Collared Crow Low Key habitat improved foraging


Crested Serpent Eagle* Very High Habitat maintained, enhanced and secured in the long-term

Little Grebe Moderate-High Feeding habitat fully compensated; additional loafing habitat provided

Little Ringed Plover Moderate-High Key habitat improved foraging opportunities provided and secured in the long-term

Pied Kingfisher Low Key habitat improved foraging opportunities provided and secured in the long-term

Striated Heron Moderate Primarily a species of mangroves and inter-tidal mudflats. Minimal direct on habitat. in addition additional loafing habitat provided; potential roosting and nesting habitat provided

Temminck’s Stint Moderate-High Key habitat improved foraging opportunities provided and secured in the long-term

White-throated Kingfisher Low Key habitat improved foraging opportunities provided and secured in the long-term

Wood Sandpiper Moderate-High Key habitat improved foraging opportunities provided and secured in the long-term

Reptiles Banded Krait Low Key habitat unaffected by construction

works and operation


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Common Rat Snake Low Key habitat improved foraging opportunities provided and secured in the long-term

Indo-Chinese Rat Snake Low Key habitat improved foraging opportunities provided and secured in the long-term

Many-banded Krait Low Key habitat unaffected by construction works and operation

Mangrove Water Snake Low Key habitat improved foraging opportunities provided and secured in the long-term

* Survey data indicate that these species only occur in the area occasionally and are unlikely to depend on the site.

13.10 Identification and evaluation of residual ecological impacts

13.10.1 An estimate of residual impacts on habitats and species, taking into account the proposed avoidance, minimisation and compensation measures proposed above are summarised in Table 13-68. The residual effects of Options 1A and 1B are predicted to be similar except in relation to habitat fragmentation.

Table 13-68 Proposed Mitigation Measures and Predicted Residual Impacts

Potential Impact Predicted Residual Impact

Habitat loss The construction of the Residential Development will result in the permanent loss of approximately 4 ha of aquaculture ponds. Enhancement works of remaining ponds within the WNR will ensure, however, that there will be no net loss of either water body area or wetland function. Advance construction of the WNR will ensure that there is sufficient alternative habitat for birds displaced by construction activities. Interim management of the WNR is expected to fully compensate functional habitat loss caused by the construction of the Residential Development and the WNR itself. Long-term management of the WNR is expected to fully compensate functional habitat loss caused by the operation of the Residential Development. No significant residual impacts from direct loss of other habitats are predicted.

Habitat fragmentation No significant fragmentation of habitats is anticipated through construction or operation of the proposed development. Some obstruction of flightlines between an egretry at Shing Uk Tsuen and the Fung Lok Wai wetlands was anticipated, although the significance of this impact was not predicted to be high. Following the abandonment of the egretry, however, no impact is now predicted. Option 1B will result in slightly greater habitat fragmentation than Option 1A. The larger number of buildings in Option 1B is expected to restrict the sightlines of birds to a slightly higher degree than would be the case in Option 1A in either case the impact is not considered to be significant for any species..

Disturbance of wildlife by noise and visual movement

The construction and operation of the residential development and WNR have the potential to disturb sensitive bird Species of Conservation Importance. Enhancement works of remaining ponds within the WNR will ensure, however, that there will be no net loss of either water body area or wetland function. Advance construction of the WNR will ensure that there is sufficient alternative habitat for birds displaced by construction activities. Phasing of works will ensure that the area affected by pond enhancement works associated with the construction of the WNR will be small at any one time. Interim management of the WNR is expected to fully mitigate disturbance effects caused by the construction of the Residential Development and the


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Potential Impact Predicted Residual Impact WNR itself. Long-term management of the WNR is expected to fully mitigate disturbance effects caused by the operation of the Residential Development. No significant residual impact from disturbance of other habitats or species other than birds is predicted.

Dust deposition on surrounding habitats

Minimal residual impact is anticipated.

Increased sediment load and pollution of watercourses

Minimal residual impact is anticipated.

Soil compaction Minimal residual impact is anticipated.

Hydrological disruption No residual impact is anticipated.

13.11 Ecological Monitoring and Audit

13.11.1 The key objective of mitigation is to maintain the functional capacity of the Fung Lok Wai wetlands during construction and operation. This will be achieved during the construction phase through interim management of ponds that are not directly affected by construction activities. The carrying capacity of these ponds will be temporarily increased through management activities known to improve habitat value for these species, primarily this will involve increasing food availability for key piscivorous waterbird Species of Conservation Importance. Mitigation targets have been specified in terms of the proportional increase in the density of Bird Species of Conservation Importance present within the mitigation area required to maintain overall population levels of these species within the Fung Lok Wai Study Area. During the operational phase of the development, disturbance is predicted to be lower and mitigation will be achieved through the long-term management of the WNR. Mitigation targets have also been identified for the same species during this phase. The mitigation targets are summarised in Table 13-69. Bird species with low target densities have not been included in this table as the mitigation targets proposed should accommodate these species when accommodating key species which are sensitive and/or have high densities. Banded Krait and Many-banded Krait have been excluded from this table because they have little reliance on fishpond habitats.

Table 13-69 Mitigation targets for Key Bird Species and other Species of Conservation Importance

Mitigation target (population increase) Species Construction phase Operation phase1

Birds Black-faced Spoonbill Double Increase by 45% Chinese Pond Heron Increase by 61% Increase by 32% Great Cormorant Double Increase by 41% Great Egret Double Increase by 45% Grey Heron Increase by 61% Increase by 32% Little Egret Increase by 92% Increase by 33% Cattle Egret Increase by 33% Increase by 32%

Other species Common Rat Snake Present Present Indo-Chinese Rat Snake Present Present Mangrove Water Snake Present Present

Note: 1 For these calculations it is assumed that mitigation will be achieved only through management to increase the carrying capacity of those fishponds unaffected by operational disturbance


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13.11.2 In addition monitoring will seek to establish the presence or absence of the marsh species listed in Table 13-66 above.

13.11.3 As indicated previously it is considered that in the period since completion of the baseline surveys that bird activity at Fung Lok Wai is likely to have declined (due to a reduction in management activity and the abandonment of the Shing Uk Tsuen egretry). Pre-construction surveys of bird populations at Fung Lok Wai will be undertaken after obtaining the planning approval and application of the lease modification / land exchange. These surveys will involve monthly counts of each pond within the Study Site for one year prior to the commencement of construction activities. The extent and timing of these surveys will, however, be agreed with AFCD prior to their commencement. All bird species observed within each pond will be recorded. Particular attention will be given to key bird Species of Conservation Importance that are specifically identified in the mitigation targets outlined above. Once these surveys are completed specific mitigation targets will be agreed with AFCD.

13.11.4 During the construction and operation phase monitoring of bird populations (along with other species, habitats and physical parameters) will be undertaken as indicated in the EM & A Manual (see also Section 14.5 below).

13.11.5 The EM&A Manual will be updated periodically to reflect ongoing discussions with AFCD and the need to revise targets in light of fluctuations to bird populations within the wider area. The selection of control sites, details of the monitoring survey methodology and arrangements for reporting on the outcomes of monitoring shall be agreed with AFCD prior to commencement of construction activities.

13.11.6 It is recommended that monitoring of the appropriate implementation of mitigation measures intended to reduce potential impacts on wildlife from, noise and vibration, dust and other forms of pollution is undertaken during construction.

13.12 References

1. Ades, (1990). Bats of Hong Kong. World Wide Fund for Nature, Hong Kong. 2. Ades, G., Anon., Cornish, A., Walthew, G. & Young, L. (1995). Focus on fishponds.

Porcupine! Newsletter of the Department of Ecology & Biodiversity, University of Hong Kong. No.13.

3. Anon. (1993). Ecological impact study of proposed development at Pak Hok Chau, Mai Po. Unpublished report.

4. Anon. (2005). Summer 2005 Report: Egretry Counts in Hong Kongwith particular reference to the Mai Po Inner Deep Bay Ramsar Site. Report by Hong Kong Bird Watching Society to the Agriculture, Fisheries and Conservation Department, Hong Kong Special Administrative Region Government.

5. Anon. (2006). Winter 2005-06 Report on Waterbird Monitoring at the Mai Po Inner Deep Bay Ramsar Site. Report by Hong Kong Bird Watching Society to the Agriculture, Fisheries and Conservation Department, Hong Kong Special Administrative Region Government.

6. Asia Ecological Consultants Ltd (AEC) (2002) Preliminary study on the potential impact of the proposed residential development at Fung Lok Wai on the egretry at Shing Uk Tsuen, and on the potential for colony relocation. Unpublished AEC report.

7. Asia Ecological Consultants Ltd (AEC) (2003). Wetland Compensation Area Ecological Monitoring and Adaptive Management Advice. Annual Report, November 2003.

8. Asia Ecological Consultants Ltd (AEC) (2004). Wetland Compensation Area Ecological Monitoring and Adaptive Management Advice. Annual Report, October 2004.

9. Asia Ecological Consultants Ltd (AEC) (2006a). Wetland Compensation Area Ecological Monitoring and Adaptive Management Advice. 2004 – 2005 Annual Report, March 2006.


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10. Asia Ecological Consultants Ltd (AEC) (2006b). Wetland Compensation Area Ecological Monitoring and Adaptive Management Advice. Supplementary Report for August – December 2005. March 2006.

11. Aspinwall (1997). Study on the Ecological Value of fish Ponds in Deep Bay Area: Executive Summary. Planning Department, Hong Kong SAR Government.

12. Aspinwall Clouston & Wetlands International – Asia Pacific (1997). Development of a comprehensive conservation strategy and a management plan in relation to the listing of Mai Po and Inner Deep Bay as a Wetland of International Importance under the Ramsar Convention. Agreement No. CE47/95.

13. Binnie, Black & Vetch HK Ltd (2000) Sheung Shui to Lok Ma Chau Spur Line Environmental Impact Assessment. Agreement No. EA990008

14. Binnie Consultants Limited (1997a). Reconnaissance survey of benthic and pelagic fishpond fauna at Fung Lok Wai. Unpublished report.

15. Binnie Consultants Limited (1997b) Tin Shui Wai Development Engineering Investigations for Development of Area 3, 30 & 31 of the Development Zone and the Reserve Zone – Environmental Impact Assessment - Final Assessment Report. Volumes 1 and 2, February 1997. Territory Development Department, Agreement No. CE 10/95.

16. Britton, A.R.C. (1993). Feeding behaviour of the Little Egret at Mai Po, Hong Kong. Hong Kong Bird Report 1992: 176-184

17. Carey, G.J., Chalmers, M.L., Diskin, D.A., Kennerley, P.R., Leader, P.J., Leven, M.R., Lewthwaite, R.W., Melville, D.S., Turnbull, M. and Young, L. (2001) The Avifauna of Hong Kong. Hong Kong Bird Watching Society, Hong Kong.

18. Carey, G. (unpublished) Ramsar Site Waterfowl Monitoring Programme, Hong Kong Bird Watching Society.

19. Cheung, K. W. 1999. Further Notes on Freshwater Fish of Hong Kong. Porcupine! 20: 10.

20. Chong, D. and Dudgeon, D. 1992. Hong Kong stream fishes: an annotated checklist with remarks on conservation status. Memoirs of the Hong Kong Natural History Society 19: 79-112.

21. Chu, W. H. (1995) Fish Ponds in the Ecology of the Inner Deep Bay Wetlands of Hong Kong. Asian Journal of Environmental Management. Vol 3, No. 1, pp13-36.

22. Collar, N. J., Crosby, M. J. and Strattersfield, A. J. (1994). Birds to Watch 2. The World List of Threatened Species. BirdLife Conservation Series No. 4. BirdLife International, Cambridge, UK.

23. Corlett, R.T. et al. (2000) Hong Kong Vascular Plants: Distribution and Status. Memoirs of the Hong Kong Natural History Society. pp1-3.

24. Endangered Species Scientific Commission (1998). China Red Data Book of Endangered Animals. Endangered Species Scientific Commission., PRC.

25. Fellowes, J.R., Lau, M., Dudgeon, D. Reels, G.T., Ades, G.W.J., Carey, G.J., Chan, B.P.L., Kendrick, R.C., Lee, K.S., Leven, M.R., Wilson, K.D.P., Yu, Y.T. (2002) Wild Animals to Watch: Terrestrial and freshwater fauna of conservation concern in Hong Kong. Memoirs of the Hong Kong Natural History Society.

26. Groombridge, B. (1993) (ed). 1994 IUCN Red List of Threatened Animals. IUCN, Gland, Switzerland and Cambridge, UK.

27. Hill, D., Hockin, D, Price, D., Tucker, G., Morris, R., and Treweek, J. (1997). Bird disturbance: improving the quality and utility of disturbance research. Journal of Applied Ecology 34: 275-288.

28. Hockin, D., Ounsted, M., Gorman, M., Hill, D., Keller, V. and Baker, M. (1992). Examination of the effects of disturbance on birds with reference to the role of environmental impact assessments. J. Environ. Mgmt 36: 253-286.

29. Holling, C. S. (ed) (1978). Adaptive environmental assessment and management. John Wiley, Chichester.


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30. IUCN (2000) The 2000 IUCN Red List of Threatened Species http://www.redlist.org/ 31. KCRC & BBVHK (2002) Sheung Shui to Lok Ma Chau Spur Line Environmental

Impact Assessment Environmental: Impact Assessment Report 32. Melville, D.S. (1987). Chinese Pond Herons Ardeola bacchus eating flies. Hong Kong

Bird Report 1987: 58-68 33. Melville, D.S, Young, L. and Leader, P.J. (1994). The importance of fish ponds around

Deep Bay to widlilfe especially waterbirds, together with a review of potential impacts of wetland loss and mitigation measures. WWF Hong Kong.

34. Mutual Luck Investment Limited (1998) Objection to Draft Lau Fau Shan & Tsim Bei Tsui Outline Zoning Plan No. S/YL-LFS/1 – Alternative Proposal. Volume 1 and 2.

35. Primavera, J.H. (2000). Integrated Mangrove – Aquaculture Systems in Asia. Integrated Coastal Zone Management, Autumn edition, pp. 121-130.

36. Pritchard, D. E. (1996) Environmental Impact Assessment: Towards Guidelines of Adoption under the Ramsar Convention. Technical Session A of the 6th meeting of the conference if the contracting parties, Brisbane, March 1996.

37. Ramsar Bureau (no date) Classification system for wetland type. www.ramsar.org 38. Tam, N.F.Y. & Wong Y.S. (1997) Ecological study on mangrove stands in Hong Kong.

Report submitted to AFD, Hong Kong SAR. 39. Townland Consultants Ltd, Wong Tung & Partners Ltd, Maunsell Consultants Asia Ltd,

MVA Asia Ltd, CES Asia Ltd, Belt Collins & Associates HK ltd, Nelson and Wright (1992). Sunnyville Estate development at Nam Sang Wai, Engineering Assessment Report, Nam Sang Wai Development Co, Ltd & Kleener Investment Ltd.

40. Town Planning Board (1999). Guidelines for application for developments within Deep Bay Area under section 16 of the Town Planning Ordinance. TPB PG-No. 12B.

41. Treweek, J. (1999). Ecological Impact Assessment. Blackwell, London, UK. 42. US Army Corps of Engineers (USACE) (1987) USACE Wetlands delineation manual.

Environmental Laboratory, US Army Engineers. Waterway Experimental Station Technical Report. Y-87-1.

43. Walters, C. J. (1986). Adaptive management of renewable resources. Macmillan, New York.

44. WWF (2000). http://www.wwf.org.hk/eng/maipo/wildlife/habitats.html 45. Wilson, K.D.P. (1995a). Dragonflies, diversity and fishponds. Porcupine! Newsletter of

the Department of Ecology & Biodiversity, University of Hong Kong. No.12. 46. Wilson, K.D.P. (1995b). Hong Kong Dragonflies, Urban Council of Hong Kong, Hong

Kong. 47. Wilson, K.D.P. (1997). An annotated checklist of the Hong Kong dragonflies with

recommendations for their conservation. Memoirs of the Hong Kong Natural History Society, 21: 1-68.

48. Wilson, K.D.P., T.W. Tam, B.S.P. Kwan, K.K.Y. Wu, B.S.F. Wong and J.K. Wong. (2004). Field Guide to the Dragonflies of Hong Kong. 2nd Eds. AFCD, Friends of Country Park and Cosmos Books Ltd. Hong Kong.

49. Wong, F.K.O. (1991) Habitat utilisation by little egrets breeding at Mai Po. Hong Kong Bird Report. 1990: 185-190.

50. Young, L. (1991). Conservation of wildlife in the Deep Bay area: with particular reference to heron species. pp. 813-822. In: Boxall, J. (ed.) Polmet '91; Pollution in the metropolitan and urban environment. Hong Kong Institution of Engineers, Hong Kong.

51. Young, L. (1993). Habitat use by herons and egrets (Ardeidae) at the Mai Po Marshes Nature Reserve, Hong Kong. Unpub. Ph.D. thesis, University of Hong Kong.