10.1 Legislation and Standards
10.3 Methodology for Baseline Establishment
10.6 Impact Identification and Evaluation
10.7 Mitigation of Adverse Impacts
10.9 Environmental Monitoring and Audit
Appendices
Appendix
10D Results of HKBCF Ecological Survey
Programme
Figures
Figure 10.1
Marine Ecological Assessment Area and Marine Ecological Sensitive Receivers
Figure
10.4c Habitat Map for Terrestrial
Ecological Assessment Area of HKLR (Airport Island)
Figure
10.5 Photographs of
Habitats presented within the Study Area
Figure
10.8 Chinese White Dolphin DPSE 2002-2009 and the HKBCF & HKLR
Project Sites
Figure
10.13 Artificial Reefs in
Airport Marine Exclusion Zone 3 and the HKBCF & HKLR Project Sites
Figure
10.14 Pre-construction Dive
Survey for Corals
10.0.1 As discussed in Section 3, various options and combinations of options for the HKBCF and HKLR have been previously investigated, evaluated, assessed and ranked, and the selected option has also been further revised and refined. The ecological impact assessment for the HKBCF and HKLR was based upon the latest layout of the preferred option.
10.1 Legislation and Standards
10.1.1 Ordinances and regulations that are relevant to this study include the following:
· Forests and Countryside Ordinance (Cap. 96) and its subsidiary legislation, the Forestry Regulations;
· Wild Animals Protection Ordinance (Cap. 170);
· Country Parks Ordinance (Cap. 208) and its subsidiary legislation;
· Marine Parks Ordinance (Cap. 476);
· Environmental Impact Assessment Ordinance (Cap. 499) and the associated TM; and
· Protection of Endangered Species of Animals and Plants Ordinance (Cap. 586) and its subsidiary legislation.
10.1.2 This assessment also makes reference to the following guidelines and standards:
·
· PELB Technical Circular 1/97 / Works Branch Technical Circular 4/97, "Guidelines for Implementing the Policy on Off-site Ecological Mitigation Measures";
· EIAO Guidance Note No. 6/2002 - Some Observations on Ecological Assessment from the Environmental Impact Assessment Ordinance Perspective;
· EIAO Guidance Note No. 7/2002 – Ecological Baseline Survey for Ecological Assessment;
· EIAO Guidance Note No. 10/2004 – Methodologies for Terrestrial and Freshwater Ecological Baseline Surveys; and
· EIAO Guidance Note No. 11/2004 – Methodologies for Marine Ecological Baseline Surveys.
10.1.3 This assessment also makes reference to the following Mainland legislation:
· List of State Protected Wild Animals, promulgated by the State Council國家重點保護野生動物名錄.
10.1.4 Other international conventions and guidelines that are relevant to this study include the following:
·
Convention on
International Trade in Endangered Species of Wild Fauna and Flora
("CITES"). This Convention regulates international trade in animal
and plant species considered to be at risk from such trade. Depending on the
degree of threat posed by international trade, CITES classifies endangered
species of animals and plants into three Appendices. Appendix I includes
highly endangered species threatened with extinction. Commercial trade in
specimens of these species is prohibited. Appendix II includes species
which are not presently threatened with extinction but may become so unless
trade is controlled. Their trade is allowed but subject to licensing controls. Appendix
III species are species identified by any Party to CITES as requiring
cooperation in controlling their trade. Their trade is subject to permits or
certificates of origin.
· IUCN - The World Conservation Union maintains, through its Species Survival Commission, a “Redlist” of globally threatened species of wild plants and animals (see http://www.iucnredlist.org/static/introduction). The Redlist is considered the authoritative publication to classify species into nine groups as Extinct (EX) - No individuals remaining; Extinct in the Wild (EW) - Known only to survive in captivity, or as a naturalized population outside its historic range; Critically Endangered (CR) - Extremely high risk of extinction in the wild; Endangered (EN) - Very high risk of extinction in the wild; Vulnerable (VU) - High risk of extinction in the wild; Near Threatened (NT) - Likely to become endangered in the near future; Least Concern (LC) - Lowest risk. Does not qualify for a more at risk category. Widespread and abundant taxa are included in this category; Data Deficient (DD) - Not enough data to make an assessment of its risk of extinction; Not Evaluated (NE) - Has not yet been evaluated against the criteria.
·
United Nations
Convention on Biological Diversity. This convention requires parties to
regulate or manage biological resources important for the conservation of
biological diversity whether within or outside protected areas, with a view to
ensuring their conservation and sustainable use. It also requires parties to
promote the protection of ecosystems, natural habitats and the maintenance of
viable populations of species in natural surroundings. The People’s Republic of
· Convention on Wetlands of International Importance Especially as Waterfowl Habitat (the "Ramsar Convention"), which requires parties to conserve and make wise use of wetlands, particularly those supporting waterfowl populations. The PRC ratified the Ramsar Convention on 31st July 1992, and various wetlands have since been listed as wetlands of international importance (i.e. Ramsar sites). One of these, Mai Po Marshes and Inner Deep Bay Ramsar site in Hong Kong SAR, was listed on 4 September 1995.
10.2 Assessment Area
10.2.1 For HKLR, the alignment covers both marine and terrestrial areas, and there are assessment areas for terrestrial ecology and marine ecology respectively. The assessment area for marine ecology (i.e. aquatic ecology in the EIA Study Brief) is the same as the water quality impact assessment area, i.e. including the following 7 Water Control Zones (WCZ) within HKSAR (Figure 10.1) as well as any areas likely to be impacted by the Project.
· Deep Bay WCZ;
· North Western WCZ;
· North Western Supplementary WCZ;
·
· Western Buffer WCZ;
·
· Second Southern Supplementary WCZ.
10.2.2 The assessment area for terrestrial ecology in HKLR is defined as all areas within 500 m from the site boundary of the land based works areas or the areas likely to be impacted by the Project. Owing to the changes of the alignment, HKLR would go through limited existing land areas, and the terrestrial ecological assessment area (Figure 10.2) has significantly reduced in size when compared with the original Study Area during the early stage of the EIA study, which is larger to cover the two conceptual alignment options in the EIA Study Brief No. ESB-110/2003.
10.2.3 For HKBCF, as it is mainly a marine project on new reclamation except some minor connecting slip roads which would involve modifications of the existing road system on Airport Island and most of them have been covered by the HKLR terrestrial ecology assessment area, the assessment area for HKBCF ecology is on marine basis. The marine ecological assessment area for HKBCF is smaller than that of HKLR, and covers the following 4 Water Control Zones (WCZ) within HKSAR as well as any areas likely to be impacted by the Project.
· North Western WCZ;
· North Western Supplementary WCZ;
· Deep Bay WCZ; and
· Western Buffer WCZ.
10.2.4 As the HKBCF marine ecological assessment area is completely covered by the larger HKLR marine ecological assessment area, the present ecological impact assessment (EcoIA) would consider the HKLR marine ecological assessment area.
10.2.5 Key issues of the EcoIA stipulated in the EIA Study Brief ESB-110/2003 and ESB-183/2008 include but are not limited to the following:
Recognized Sites of Conservation Importance
· Tai Ho Stream Site of Special Scientific Interest (SSSI): Tai Ho Stream and inner Tai Ho Wan, important for stream fish, seagrasses, mangroves, and horseshoe crab;
·
·
Lantau North
(Extension)
· San Tau Beach Site of Special Scientific Interest (SSSI): with records of seagrasses and mangroves, a horseshoe crab nursery site;
·
Sha Chau and
·
The proposed marine
parks at Fan Lau and
·
Mai Po Inner Deep Bay
Ramsar Site.
Important Habitats
·
West Lantau and
· Inter-tidal mudflats;
· Mangroves;
· Seagrass beds;
· Horseshoe crab breeding and nursery grounds along the northwest Lantau coastlines including Sham Wat, Hau Hok Wan, San Tau, Tung Chung and Tai Ho Bay;
· Horseshoe crab nursery site at Shui Hau;
· Woodlands;
· Wetlands;
· Natural stream courses and rivers;
·
Scenic Hill on
· Artificial reefs.
Species of Conservation Importance
· Vertebrates: fish, herpetofauna, avifauna, and mammals including bats;
· Macro-invertebrates: butterflies, odonates, crustaceans;
· Inter-tidal and sub-tidal benthic communities;
· Coral communities (including all hard corals, octocorals and black corals);
· Chinese White Dolphin Sousa chinensis (CWD);
· Horseshoe crabs and any other notable marine benthic or littoral communities;
· White-green sedge (Carex leucochlora); and
· Any other habitats and wildlife groups identified as a special conservation concern by this EIA study.
10.3 Methodology for Baseline Establishment
10.3.1 Introduction
10.3.1.1 The establishment of baseline conditions should include:
· Description of the physical environment;
· Description and quantification of the ecological resources (e.g. wildlife abundance, habitat sizes, food resources); and
· Identification of habitats or locations (e.g. feeding grounds, nursery grounds) that are important to wildlife.
10.3.1.2
Taking account of
various factors, the present EIA study covers approximately 6 years (from 2003
– 2009) which is quite long when compared with other EIA studies. The
ecological survey programmes for this Project (directly for this EIA or
associated with other elements under the Project) were also covered a long time
period. Since the commencement of the EIA study for the “Hong Kong –
Zhuhai –
10.3.1.3
To supplement the
information obtained from literature reviews, an Ecological Baseline Survey for
the HZMB/NLHC Project (i.e. Hong Kong –
10.3.1.4
The Study Area for the EBS
covers a large area from Tai Ho to Sham Wat and the southern portion of
10.3.1.5 Since the completion of the EBS, the alignment of the HZMB and the NLHC were reviewed and significantly changed due to various considerations including potential ecological impacts on sensitive ecological resources. During this design review stage, field visits (mainly in the eastern and middle part of the study area of EBS) and update of literature information (mainly other EIA studies in the area e.g. “Extension of Siu Ho Wan Water Treatment Works – Investigation”, and “Feasibility of Lantau Logistics Park”) were continued.
10.3.1.6
In mid 2008, when the
HKLR alignment (the original HZMB Hong Kong Section and NLHC) was formulated
(see Section 3), a large-scale Ecological Verification Survey (hereafter
referred as EVS) was conducted for a duration of 6 months (August 2008
to January 2009) covering wet and dry seasons to verify the validity of the
ecological data and information collected in the previous EBS as well as
from previous literature update and field visits, so as to establish an updated
ecological baseline conditions. The items and survey methods applied in
this EVS followed those in the EBS, but the area coverage was
shifted to the 500m distance area of the new alignment which mainly follows the
airport channel or is located on
10.3.1.7
Tuen Mun-Chek Lap Kok
Link (TMCLKL), which is interfacing with the HKLR and HKBCF projects, is
proposed to provide a traffic link between Tuen Mun and
10.3.1.8
In late 2008, the
section of HKLR to the east of
10.3.1.9 All these survey programmes and studies since the commencement of the HKLR EIA study have provided sufficient ecological data over a long time period.
10.3.1.10
The HKBCF EIA study
commenced in 2008 after the governments of Hong Kong, Zhuhai and
10.3.1.11 Secondly, there have been many EIA studies and research projects conducted in the vicinity of the Project Site as well as the marine ecological assessment area (particularly North Lantau waters).
10.3.1.12
Available information
includes the studies of CT10 at
10.3.1.13 “CT10 (Proposed Port Development at Northwest Lantau)” covered a comprehensive ecological survey programme including a 12-month dolphin survey on the Pearl River Estuary, intertidal survey and horseshoe crab survey in North Lantau area.
10.3.1.14
“New Contaminated Mud
Marine Disposal Facility at Airport East / East Sha Chau Area” was an EIA study
covering the waters to the north and to the east of
10.3.1.15
“Liquefied Natural Gas
(LNG) Receiving Terminal and Associated Facilities” included two option sites
at Black Point and Soko Islands. The study area covered Northwest, West
and
10.3.1.16 Indirect impacts to habitats and communities within the 500m radius are also anticipated to be limited for the following reasons:
· Areas adjacent to the proposed reclamation site are existing urbanised/disturbed lands (i.e. Airport Island) already subject to high levels of disturbance from road traffic along the coastlines, and therefore of very low ecological value;
· The nearest natural terrestrial habitats (Scenic Hill) are over 500m boundary from the reclamation site and are separated from the reclamation site by urbanised/disturbed lands in between; and
·
The only directly
affected terrestrial areas would be the existing road system (developed areas)
on
10.3.1.17 The assessment area for marine ecology in the present EcoIA covers a large sketch of sea areas including 7 water control zones. Besides the four coastal and marine recognised sites of conservation importance in Northwest waters as stipulated in the EIA study brief (i.e. Tai Ho Stream SSSI which also covers the inner Tai Ho Wan, San Tau Beach SSSI, Sha Chau and Lung Kwu Chau Marine Park and the proposed Marine Park at Fan Lau), there are a few others inside the assessment area but far away from the HKLR and HKBCF sites, including Lung Kwu Chau, Tree Island & Sha Chau SSSI, Pak Nai SSSI, Mai Po Inner Deep Bay Ramsar Site, Inner Deep Bay SSSI, Tsim Bei Tsui SSSI, Shui Hau in South Lantau, the proposed marine park in Soko Islands, Sham Wan SSSI in south Lamma, and Cape d’Aguilar Marine Reserve in Hong Kong Island (see Figure 10.1). As most of these sites are far away and sheltered from the project site by Lantau Island, they would be unlikely to be impacted by HKLR and HKBCF, as indicated by water quality assessment results (sediment plume would be limited to the vicinity of the reclamation sites, and other water quality criteria would be complied, see Section 9). The present EcoIA on marine ecology would thus focus on the North Western Water Control Zone and North Western Supplementary Water Control Zone.
10.3.1.18 Given the above considerations, the best approach for establishing an updated and valid ecological baseline for the Project would be to verify the information collected from previous ecological surveys, recent or ongoing studies/research projects as well as to fill any identified gaps in data coverage by the recent field surveys (i.e. EVS, MSS and HKBCF field survey programme).
10.3.1.19 Information from literature review and field surveys facilitated the identification, prediction and evaluation of ecological impacts potentially arising from the construction and operation of the Project.
10.3.2 Literature Review Methodology
10.3.2.1 Relevant ecological studies were thoroughly reviewed, including those listed in Appendix E of the EIA Study Brief ESB-110/2003. Other relevant sources, including the Terrestrial Biodiversity Survey conducted by HKU, ongoing Biodiversity Survey conducted by AFCD, ongoing academic research and data-gathering efforts (e.g. HK Bird Watching Society, Hong Kong Lepidopterist’s Society) were also reviewed. Species groups of concern were identified based on background information on the study areas, field survey results from EBS, EVS, MSS of HKLR and ecological surveys of HKBCF, and consultation with relevant government authorities. Desk-top study and field survey results produced a complete picture of the ecology of the assessment area. Major literature more relevant to the present EIA study included:
· “Population Biology of the Indo-Pacific Hump-backed Dolphin in Hong Kong Waters”, Wildlife Monographs 2000 October No. 144: 1-65;
·
“Distribution and
abundance of Finless Porpoises in Hong Kong and adjacent waters of
·
“Monitoring of Marine
Mammals in
·
“Monitoring of Chinese
White Dolphin (Sousa chinensis) in
·
“Habitat
use by
·
“Avifauna
of
·
“Consultancy Study on
Marine Benthic Communities in
·
“Conservation of Horseshoe
Crabs in
· “Ecological Status and Revised Species Records of Hong Kong’s Scleractinian Corals” (AFCD 2004);
· “Field Guide to Hard Corals of Hong Kong” (Chan et al. 2005).
· Annual report and other publications of The Hong Kong Bird Watching Society;
·
Memoirs of
·
Porcupine! – newsletter
of Department of Ecology & Biodiversity of
· Biodiversity – newsletter of AFCD; and
· Other relevant reports from private sectors or Government.
10.3.2.2 Relevant information contained in the above reports was incorporated into this EcoIA.
10.3.2.3 Other relevant EIA studies included:
· The Feasibility Study of Additional Cross-border Links, Stage 2 (Crosslinks Further Study Stage 2);
· Remaining Development in Tung Chung and Tai Ho Comprehensive Feasibility Study;
· Airport EIA study;
· Agreement No. CE 32/96 Study on Tonggu Waterway;
· EIA-040/2000 Northshore Lantau Development Feasibility Study;
·
EIA-042/2000 Tai O
Sheltered Boat
·
EIA-075/2002
Improvement to
· EIA-082/2002 Shenzhen Western Corridor;
·
EIA-077/2002 Permanent
Aviation Fuel Facility for
· EIA-081/2002 Construction of Lung Kwu Chau Jetty;
·
Proposed Port Development
at
· EIA 090/2003 Tung Chung – Ngong Ping Cable Car Project;
· EIA 100/2004 Extension of Siu Ho Wan Water Treatment Works – Investigation (Metcalf & Eddy Ltd. 2004);
· EIA 106/2005 New Contaminated Mud Marine Disposal Facility at Airport East / East Sha Chau Area;
· EIA 125/2006 Liquefied Natural Gas (LNG) Receiving Terminal and Associated Facilities; and
· EIA study for Feasibility of Lantau Logistics Park.
10.3.2.4 The validity of the information compiled during the literature review was assessed before it had been adopted into the present EIA study and was verified on-site during the ecological field surveys for the present Project (see below).
10.3.3 Identification of Information Gap
10.3.3.1
Surveys on Chinese
White Dolphin have been conducted in Hong Kong waters since 1996 and have also
been conducted off
10.3.3.2 While for other aspects on ecology, field surveys for the purpose of verifying and updating the information from literature were proposed. The scope of the field surveys covered habitat, vegetation, terrestrial fauna, intertidal fauna, marine benthic communities and corals. Details of the surveys are given in below sections.
10.3.4 Ecological Field Survey Methodology
9-month Ecological Baseline Survey for HZMB / NLHC (EBS)
10.3.4.1
The Study Area for the
EBS (the same as the Study Area of the HZMB Project as shown in Appendix H in
the Brief for the Project) covers a large area from Tai Ho to Sham Wat and the
southern portion of
10.3.4.2 The field surveys of the EBS covered all marine and terrestrial sites, habitats and species of conservation within the study area (Figure 10.3), and included the following items:
· Habitat survey and mapping;
· Vegetation survey with special attention on seagrass beds and mangroves;
· Bird survey;
· Terrestrial invertebrate survey;
· Herpetofauna survey;
· Mammal survey;
· Freshwater fish survey;
· Freshwater invertebrate survey;
· Intertidal epifauna survey;
· Horseshoe crab survey;
· Subtidal benthic infauna survey;
· Coral survey; and
· Chinese White Dolphin study based upon literature.
10.3.4.3 Findings of the EBS were incorporated into the baseline description of the study area in the survey report. Readers are referred to the final survey report for the EBS (Appendix 10A) for details of survey methods and data.
Ecological Verification Survey (EVS)
10.3.4.4 When the EIA study for the HKLR resumed in 2008, a large-scale and comprehensive Ecological Verification Survey (EVS) was planned, to verify the validity of the existing ecological data previously collected and to update the ecological baseline information before the detailed assessment is performed.
10.3.4.5
The items and survey
methods applied in this EVS followed those in the EBS, but the area coverage
was shifted to the 500m distance area along the new alignment which mainly
follows the airport channel or is located on
10.3.4.6
Terrestrial surveys
(see below sections) were conducted in all the land areas within 500m from the
mid-2008 HKLR alignment (see Figure 10.3),
on North Lantau and
10.3.4.7
It is noted that the
eastern part of the mid-2008 HKLR alignment (the sea viaduct offshore to the
eastern coast of Airport Island) was revised in late 2008 to an at-grade road
along the airport island shoreline on new reclamation, so as to reduce the
visual impact to Tung Chung Town. Under the latest alignment, additional
land areas on
10.3.4.8 Habitat and vegetation surveys were conducted within in the 500m area. Surveys covered all habitat types. The survey locations are selected prior to the field survey through aerial photographs and data from the baseline survey. During the surveys, the locations of rare or protected plant species were recorded with their number, and photos were taken. Lists of the plant species recorded in wet and dry seasons in each habitat with relative abundance were provided. Plant species which were not reported in the EBS but are found in the EVS were highlighted. A habitat map of suitable scale was provided.
10.3.4.9 Mammal surveys - Traces, tracks and scats of mammals were searched and recorded. Since most mammals are nocturnal, night surveys were also conducted. All mammals were identified to species level and the abundance was recorded. Lists of the mammal species recorded in wet and dry seasons in each habitat with abundance were provided.
10.3.4.10
Reptile and
amphibian surveys
in the 500m distance area were conducted by active searching in all habitats,
with particular attention given to potential shelters sites and hiding places
such as litters, streams and watercourses. Special attention was paid on
Scenic Hill on
10.3.4.11 Avifauna surveys - Transect count method was used to survey the avifauna present in the 500m distance area. Sampling transects were recorded on map. In addition, night surveys, with binoculars and powerful search lights, were conducted in order to assess the activity of nocturnal species, e.g., owls, nightjars. All birds were identified to species level and the abundance was recorded. List of the bird species recorded in wet and dry seasons in each habitat with abundance was provided.
10.3.4.12 Dragonfly surveys - Dragonflies were surveyed following the same transects used for bird surveys. Dragonflies were identified with the aid of binoculars, and a telescopic hand net was used to capture specimens for identification in the hand (when necessary). All dragonflies were identified to species level and the abundance was recorded. Lists of the dragonfly species recorded in wet and dry seasons in each habitat with abundance were provided.
10.3.4.13 Butterfly surveys were conducted in tandem with the dragonfly surveys, using similar methodology. Potential microhabitats, e.g., ground and canopy of woodland were searched and sweep with a long-handled (5m) butterfly net. All butterflies were identified to species level and the abundance was recorded. Lists of the butterfly species recorded in wet and dry seasons in each habitat with abundance were provided.
10.3.4.14 Stream surveys - Fish and invertebrates present in streams within the 500m distance area were identified and recorded by direct observation, dip-netting and active sampling. All aquatic fauna were identified to species level as far as possible and abundance recorded. Lists of the aquatic species recorded in wet and dry seasons in each stream with abundance were provided.
10.3.4.15
Intertidal surveys were conducted on both hard
(including natural and artificial coastlines) and soft shores along the Airport
Channel and on
10.3.4.16 Horizontal transects (at least 50m in length) at three tidal levels (High, Middle and Low) were established on each of the landing points of HKLR covering natural and artificial coastlines. There were ten 0.5m x 0.5m quadrats on each transect. The epifauna in each quadrat were identified and their numbers/coverage percentages were recorded. Species and abundance of biota in quadrats were reported. Diversity index, evenness index and other statistical analyses were provided for evaluating and ranking the ecological values.
10.3.4.17 Detailed active search surveys along the shores were also conducted to find out the species present and their occurrence in the survey locations in addition to the transect surveys, so as to produce a comprehensive species lists of the survey areas. Photos of the recorded species were taken where possible.
10.3.4.18 The embayments along and in the vicinity of Airport Channel, namely Sham Wat, San Shek Wan, Sha Lo Wan, Hau Hok Wan, San Tau and Tung Chung Bay, were surveyed.
10.3.4.19 In each site, horizontal transects (at least 50m in length) at three tidal levels (High, Middle and Low) were established. There were ten 0.5m x 0.5m quadrats on each transect. The epifauna and infauna (within the top 5cm sediment) in each quadrat were identified and their numbers/coverage percentages were recorded. One core of 10cm diameter x 20cm depth was also collected within each quadrat. The sediments of the cores was sieved with 2mm mesh-size sieve and the biota inside were identified and counted. Species and abundance of biota in both cores and quadrats were reported. Diversity index, evenness index and other statistical analyses were provided for evaluating and ranking the ecological values.
10.3.4.20 Seagrass surveys and horseshoe crab surveys were also conducted at the above soft shore sites. The sites were thoroughly searched for the seagrasses and horseshoe crabs during suitable ebbing tides. The species, number, sizes of horseshoe crabs and the species, area sizes and coverage percentages of seagrasses were recorded, and the locations of horseshoe crabs and the locations and extents of seagrasses were mapped. Photos of seagrasses and horseshoe crabs found during the surveys were taken.
10.3.4.21 Dive surveys for corals and other hard substrate marine organisms were conducted. As spot dives within and outside the Airport Channel had been previously conducted during the 9-month ecological baseline survey, the verification survey concentrated on shallow coastal waters that are potentially subject to direct loss of marine habitats, including the landing points of HKLR at both natural and artificial coastlines along Airport Channel and on Airport Island, and indirect impacts due to change of water quality and hydrodynamic condition, including the coastlines to the east and to the west of Airport Channel.
10.3.4.22 Semi-quantitative Rapid Ecological Assessment (REA) surveys were conducted at each survey location. The REA survey was performed along 100m underwater transects horizontal to the coastlines. Transects perpendicular to the coastline of 50m to 100m (subject to the underwater visibility) was also performed. The depth and substrate along the perpendicular transects for REA were recorded at 3m intervals, or at smaller intervals if the gradient significantly changes along the transects. The benthic cover, taxon abundance, and ecological attributes of the transects were recorded in a swathe of 2m wide, 1m either side of the transects (subject to the underwater visibility), following the Rapid Ecological Assessment (REA) technique. The exact locations and routes of the REA transects were recorded on site by GPS and map. Video footages and photos along the transects and of the surveyed areas were taken during the dive surveys.
10.3.4.23 The purposes of the REA survey are to quantitatively record the habitat types and ecological values of the area by SCUBA diving and the application of Rapid Ecological Assessment (REA) approach. The REA approach (see Annex A in Appendix 10B for details) will aim at collecting data on the type of substrate and the abundance of marine organisms in particular the occurrence of corals and the extent of the coral distribution from the coastline, for ranking the ecological values. Other parameters to be recorded during the surveys included site condition (e.g. observations regarding the degree of exposure of the sites to wave action), species list of corals and other marine organisms, coral sizes, coral health status, and translocation feasibility of corals.
10.3.4.24 Marine grab samplings on soft substrate seabed for benthic communities were conducted at 9 stations along the mid-2008 HKLR alignment during both wet season and dry seasons (September 2008 and December 2008). Three grab sample replicates of 0.1m2 were collected in each of the sampling stations by van Veen Grab (or other sampling devices with equivalent surface area coverage). Collected samples were sieved by 0.5mm mesh-size sieve and then preserved in 5% buffered seawater formalin. Organisms inside the samples were sorted from the sediments by staining with Rose Bengal and then identified to the lowest practicable taxonomic level. Species composition, abundance and biomass were reported. Diversity index, evenness index, Abundance/Biomass Comparison (ABC) plots and other statistical analyses should be provided for evaluating and ranking the ecological values.
HKBCF Ecological Survey
10.3.4.25
HKBCF is a new element
for the HZMB after 2008. It would involve large-scale reclamation near
the
10.3.4.26
Dive surveys for corals and other hard substrate
marine organisms were conducted in September 2008. The dive surveys
concentrated on shallow coastal waters that would be subject to direct loss of
marine habitats or indirect water quality impacts, including both natural and
artificial coastlines at the northeast of
10.3.4.27
Spot reconnaissance
dives were conducted 17 spot-check dives were conducted and covered: 1) along
the coastlines of Northeast Airport Island (8 spots), with focus concentrated
on the section opposite to the future BCF reclamation area, ; 2) as well as
within the future BCF reclamation area covering the entire proposed reclamation
site (9 spots). The locations for spot reconnaissance dives are shown in Figure 10.3 and Appendix 10D. Visual
reconnaissance was made of the area of each bounce dive point. The purposes of
the spot reconnaissance dives are to verify whether corals (including all hard
corals, octocorals and black corals) and other marine organisms with
conservation importance are present within the areas potentially subject to
direct impacts (e.g. the reclamation area and the fire station seawalls) and
indirect impacts (e.g. some sections of the Airport Island coastlines).
As the underwater visibility is low in
10.3.4.28
In accordance with the
findings from the spot-check dives, a REA was conducted along the seawall which
was found to be the only area with hard bottom substrate habitat within the
dive survey study area. Semi-quantitative Rapid Ecological Assessment
(REA) survey was conducted at the two major locations, i.e. where the BCF
connecting on
10.3.4.29 The purposes of the REA survey are to quantitatively record the habitat types and ecological values of the area by SCUBA diving and the application of Rapid Ecological Assessment (REA) approach. The REA approach aims at collecting data on the type of substrate and the abundance of marine organisms in particular the occurrence of corals and the extent of the coral distribution from the coastline, for ranking the ecological values. Other parameters to be recorded during the surveys included site conditions (e.g. observations regarding the degree of exposure of the sites to wave action), species list of corals and other marine organisms, coral sizes, coral health status, and translocation feasibility of corals.
10.3.4.30 Marine grab samplings for benthic communities were conducted at 9 stations within the BCF reclamation area (see Figure 10.3) during both wet season and dry season (September and December 2008). Five grab sample replicates of 0.1m2 were collected in each of the sampling stations by van Veen Grab. Collected samples were sieved by 0.5mm mesh sieve and then preserved in 5% buffered seawater formalin. Organisms inside the samples were sorted from the sediments by staining with Rose Bengal and then identified to the lowest practicable taxonomic level. Species diversity, abundance and biomass were reported for evaluating and ranking the ecological values.
10.3.4.31
Intertidal surveys for epifauna communities were
conducted on both natural and artificial coastlines at the northeast of
10.3.4.32
Horizontal transects at
three tidal levels (High, Middle and Low) were established on each of the
natural and artificial coastlines and cover the landing points of the
connecting roads on
10.3.4.33 In addition to the above quantitative surveys, walk-through surveys were also conducted in the survey extent to facilitate the smooth implementation of the ecological survey and to help audit the survey findings. Walk-through survey aimed at to find out the species present and their occurrence and hence facilitate the determination of representative sites for conducting quantitative surveys. Effort spent in walk-through surveys, such as number of surveyors involved and time-spend were recorded.
HKLR Marine Supplementary Survey
10.3.4.34
Intertidal surveys for epifauna communities were
conducted at four locations on the southeast shore of
10.3.4.35 In each location, horizontal transects (at least 50m in length) at three tidal levels (High, Middle and Low) were established. There were ten 0.5m x 0.5m quadrats on each transect. For hard shores, the epifauna in each quadrat were identified and their numbers/coverage percentages were recorded. For the soft shores, in addition to the epifauna, the infauna within the top 5cm sediment inside the quadrat as well as from one core (10cm diameter x 20cm depth) collected inside the quadrat were also identified and recorded. Species and abundance of biota in quadrats were reported. Diversity index, evenness index and other statistical analyses were provided for evaluating and ranking the ecological values.
10.3.4.36 In addition to the above quantitative surveys, walk-through surveys were also conducted in the survey extent to facilitate the smooth implementation of the ecological survey and to help audit the survey findings. Undertaking an initial observation along the shore, for example, could find out the species present and their occurrence and hence facilitate the determination of representative sites for conducting more detailed quantitative surveys. A walk-through survey along the transect during or after a quantitative sampling event could also help assess whether the sampling exercise has collected representative data (e.g. the number and type of species encountered) and whether the sampling effort is deemed adequate. Effort spent in such qualitative surveys, such as number of surveyors involved and time spent were recorded.
10.3.4.37
Dive surveys for corals and other hard substrate
marine organisms were conducted. The dive surveys focused on shallow coastal
waters within the survey extent, i.e. both natural and artificial coastlines at
the southeast of
10.3.4.38
Spot reconnaissance
dives were conducted along the coastlines of
10.3.4.39 Circular paths at each dive spots were adopted during the reconnaissance dives as the underwater visibility is found too low for continuous routes. Besides the biota, the habitat types present within the areas and their approximate proportions/distributions were also recorded. Photos of each spot dive locations, underwater photos, and underwater video footages were taken during the spot dive surveys.
10.3.4.40 In accordance with the findings of the spot dives, semi-quantitative Rapid Ecological Assessment (REA) surveys were conducted in two locations within the survey extent. The REA surveys were performed along 100m underwater transects horizontal to the coastlines. Transects perpendicular to the coastline of 50m to 100m (subject to the underwater visibility) were also performed. The depth and substrate along the perpendicular transects for REA were recorded at 3m intervals. The benthic cover, taxon abundance and ecological attributes of the transects were recorded in a swathe of 2m wide, 1m either side of the transects, following the REA technique. The exact locations and routes of the REA transects were recorded on site by GPS and map. Photos of each REA locations, underwater video footages and underwater photos along the transects and of the surveyed areas were taken during the REA dive surveys.
10.3.4.41 The purposes of the REA survey are to quantitatively record the habitat types and ecological values of the area by SCUBA diving and the application of REA approach. The REA approach aimed at collecting data on the type of substrate and the abundance of marine organisms in particular the occurrence of corals and the extent of the coral distribution from the coastline, for ranking the ecological values. Other parameters to be recorded during the surveys included site condition (e.g. observations regarding the degree of exposure of the sites to wave action), species list of corals and other marine organisms, coral sizes, coral health status, and translocation feasibility of corals. The conservation status of the recorded biota were provided.
10.3.4.42 Marine grab samplings on soft substrate seabed for benthic communities were conducted at eight stations within the survey extent during both wet season and dry season (December 2008 and May 2009). The survey extent and the indicative sampling locations are shown in Figure 10.3. Five grab sample replicas of 0.1m2 were collected in each of the sampling stations by van Veen Grab (or other sampling devices with equivalent surface area coverage). Collected samples were sieved by 0.5mm mesh-size sieve and then preserved in 5% buffered seawater formalin. Organisms inside the samples were sorted from the sediments by staining with Rose Bengal and then identified to the lowest practicable taxonomic level. Species composition, abundance and biomass were reported. Diversity index, evenness index and Abundance/Biomass Comparison (ABC) plots were provided for evaluating and ranking the ecological values. The conservation status of the recorded biota were provided.
TMCLKL Ecological Survey
10.3.4.43
TMCLKL ecological survey
programme covered a 9-month period. Besides the terrestrial surveys
conducted in Tuen Mun and Tai Ho (both are outside the current 500m terrestrial
assessment area for the present Project), the TMCLKL survey also included
marine and intertidal surveys in
10.3.4.44 Details of the methodology of the ecological surveys for TMCLKL are provided in the separate EIA Report for TMCLKL.
10.4 Baseline Conditions
10.4.1 Terrestrial Ecological Baseline within the EBS Study Area
10.4.1.1 The below Sections 10.4.1 and 10.4.2 cover fauna and flora in terrestrial habitats including freshwater streams.
Terrestrial Sites of Conservation Importance within the EBS Study Area and the current 500m Assessment Area
10.4.1.2
The original Assessment
Area for terrestrial ecological impact assessment of the Project (i.e. the
study area for the 9-month EBS) is located in
10.4.1.3 The recognised sites of conservation importance within this original assessment area include (Figure 10.2):
· Tai Ho Stream SSSI;
· Pok To Yan and Por Kai Shan SSSI;
·
· San Chau SSSI;
·
Lantau North
(Extension)
· San Tau Beach SSSI.
10.4.1.4 Other sites in the original assessment area that have been identified during the EIA as of conservation importance include:
· Bat roost in Tai Ho Wan;
· Pak Mong fung shui wood;
· San Tau fung shui wood;
· Sha Lo Wan fung shui wood; and
·
The Scenic Hill on
10.4.1.5
However a larger
portion of these sites of conservation importance are now outside the current
500m assessment area and far away from the HKLR footprint. Only three of the
above sites of conservation importance still fall within the current 500 m
assessment area, i.e. Lantau North (Extension)
10.4.1.6
Lantau North
(Extension)
10.4.1.7
Scenic Hill is a small
hill at the southeast end of
10.4.1.8
Before construction of
the airport, Chek Lap Kok was one of the few islands on which Romer’s Tree Frog
was found in
10.4.1.9 San Tau Beach SSSI is a seagrass site and is described in the sections on intertidal ecology below.
Habitats and Vegetations inside the EBS Study Area
10.4.1.10 The habitats recorded within the study area for the EBS include secondary woodland, plantation woodland, tall shrubland, shrubby grassland, cultivated land, mangrove and seagrass, salt marsh, stream, wasteland, and developed area (see Appendix 10A). The information of terrestrial habitats is given in the sections below, while intertidal habitats such as mangrove & seagrass and salt marsh are discussed under the sections on intertidal ecology.
Table 10-1 Coverage of Different Habitats within the Study Area for the EBS
Habitat Type |
Area (ha) |
No. of plant species recorded |
Secondary |
302.54 |
217 |
|
6.57 |
125 |
Tall Shrubland |
22.17 |
185 |
Shrubby Grassland |
191.8 |
153 |
Cultivated Land/Orchard |
59.9 |
126 |
Mangrove and Seagrass |
10.57 |
85 |
Salt Marsh |
1.63 |
74 |
Stream/riparian |
5.36 |
N/A |
Wasteland |
2.64 |
159 |
Developed Area |
483.9 |
129 |
10.4.1.11 A total of 475 plant species were recorded within the study area (Appendix 10A). The description of habitats below follows Appendix 10A unless otherwise specified.
Secondary
10.4.1.12 Notable woodland patches can be found at Tai Ho Wan headland and adjacent to Sha Lo Wan San Tsuen. This habitat is extensive and relatively rich in flora with a total of 217 recorded plant species.
10.4.1.13 Major/dominant plant species included trees Aporosa dioica, Bridelia tomentosa, Litsea glutinosa, Mallotus paniculata, Schefflera octophylla and Sterculia lanceolata. Dominant shrub species included Litsea rotundifolia, Ilex asprella and Psychotria rubra. Of the plant species recorded, only the shrub Pavetta hongkongensis was protected under the law but this species in considered common (Xing et al. 2000).
10.4.1.14 Woodlands within the study area also consisted of fung shui woods at Tung Chung near the villages of San Tau and Sha Lo Wan.
10.4.1.15
Tall Shrubland
10.4.1.16
Tall shrubland occurred
along the coast of
10.4.1.17 A total of 185 plant species were recorded in this habitat. Species found commonly in this habitat included trees such as Acronychia pedunculata, Cratoxylum cochinchinense, Schefflera octophylla, Rhus succedanea and Mallotus paniculatum, Sapium discolor; the shrubs Eurya japonica, Litsea rotundifolia, Melastoma sanguineum and Rhaphiolepis indica, the climbers Alyxia sinensis, Lygodium japonicum, Cassytha filiformis, Tetracera asiatica and Embelia ribes; as well as the herbs Dianella ensifolia and Dicranopteris pedata.
10.4.1.18 Carex tristachya is a rare sedge (Xing et al. 2000) recorded in this habitat in Hau Hok Wan and patches of the orchid Eulophia graminea were found near tall shrubland habitats at Hau Hok Wan and Sha Lo Wan. The locally protected Pavetta hongkongensis was also recorded in this habitat.
Shrubland-Grassland Mosaic
10.4.1.19 The shrubby grassland is composed of a range of plant species showing various growth forms (from herbaceous ferns to woody tree species) that are patchily distributed on the hill-slopes and mostly located at higher elevations. Generally, this habitat type is open in structure and has a vegetation height of less than 2m. Moreover, it is believed that part of this mosaic may be disturbed frequently by hill-fire as evidenced by the presence of patches of the fire-resistant fern Dicranopteris pedata, especially in the areas behind the burial grounds.
10.4.1.20
153 plant species were
recorded in this habitat. Trees were not particularly diverse and most common
species included Ficus variolosa, Aporosa dioica and Cratoxylum
cochinchinense. However, many shrub species were recorded including Baeckea
frutescens, Aster baccharoides, Breynia fruticosa, Melastoma
sanguineum and Helicteres angustifolia. Herbs included
Arundinella setosa, Eremochloa ciliaris, Eulalia spp.,
Grewia biloba, Inula cappa, Ischaemum rugosum together with
climbers, Alyxia sinensis, Cassytha filiformis, Lygodium
japonicum, Millettia nitida and Morinda umbellata. Plant
species in this habitat were similar to those present in the tall shrubland
although fewer tree species were recorded. Three protected orchids Acampe
rigida, Arundina chinensis and Cleisostoma simondii were recorded in
this habitat. Although all three species are common in Hong Kong (Siu 2000),
all members of the orchid family (Orchidaceae) are protected under the Forestry
Regulations in
Cultivated Field / Orchard
10.4.1.21 Cultivated field/orchards include both active, inactive cultivation and orchards. Cultivated fields are mainly scattered among the village areas and mostly distributed along the coast of the study area. These are planted with fruit trees and ornamental plants such as Litchi chinensis, Dimocarpus longan, Clausena lansium, Citrus sp., and some widespread herbs including Lantana camara, Solanum torvum and Lygodium japonicum. A total of 126 plant species were present in this habitat although no rare or protected plant species was recorded.
Stream / Riparian
10.4.1.22 Many stream courses in the EBS study area are seasonal, or of very low base flow. These low base-flow streams are considered of lower ecological value than the permanent streams with reliable discharge to support aquatic life year-round.
10.4.1.23 The streams in the study area pass through various vegetated habitats such as woodlands, grassland-shrubland mosaic and cultivated fields. Riparian vegetation is broadly similar to that of the surrounding habitats, comprising secondary woodland and shrubby grassland.
Wasteland
10.4.1.24 Wasteland is mostly found in heavily disturbed or previously developed areas. This habitat type is poorly represented within the EBS study area.
10.4.1.25 In general, the species diversity of this habitat is poor and its structural complexity is simple. The vegetation on wasteland is dominated by weedy herbaceous ruderal plants; such as the common herbs, Cynodon dactylon, Panicum maximum, Lygodium japonicum and the climbers Mikania micrantha and Pueraria lobata.
Developed Area
10.4.1.26 The developed area refers to urbanised areas including roads, buildings and villages that can be found in Chek Lap Kok, Tung Chung and some scattered in the western part of the study area. This habitat is man-made.
10.4.1.27
The vegetation is
predominantly composed of herbs and climbers, and occasionally with some planted
or orchard trees such as Casuarina equisetifolia, Bambusa sp., Clausena
lansium and Averrhoa carambola. Despite some observations of
restricted species, the 129 plant species recorded in the developed areas are
common and widespread in
Terrestrial Fauna inside the EBS Study Area
Mammals inside the EBS Study Area
10.4.1.28 Only two species of non-flying mammals were recorded in the EBS study area (Table 5.14 in Appendix 10A). These were the Indian Muntjac Muntiacus muntjak and Brown Musk Shrew Suncus murinus. Both are considered locally common (Appendix 10A). Sighting of Indian Muntjacs was made within the terrestrial study area of the EBS at tall shrubland at Sham Shek Tsuen in April 2004. Unidentified insectivorous bats were observed at Tai Ho Wan, Sham Wat and San Shek Wan during night surveys in February, April and May 2004 (ibid.).
10.4.1.29
Diversity of medium to
large non-flying mammals on Lantau is low. Three species of non-flying mammal,
i.e. the Chinese Ferret Badger Melogale moschata, Wild Boar Sus
scrofa and Indian Muntjac were recorded on
10.4.1.30 A number of rodents, including Sikkim Rat Rattus sikkimensis, R. rattus flavipectus, Norway Rat R. norvegicus and Bandicota indica were recorded at Chek Lap Kok by Chandrasekar-rao (1994). Rattus r. flavipectus was recorded at the back of the Tung Chung mangal, near cultivated land in July and August 2002 during the field surveys for the EIA of Tung Chung Cable Car Project (Mott 2003). Several burrows of the species were present in adjacent bunds at the backshore and in adjacent abandoned cultivated land.
10.4.1.31
A Least Horseshoe Bat Rhinolophus
pusillus roost was found near Pak Mong within the Terrestrial Study Area
(Ades 1999). Four bat species were reported in Tung Chung (Lin 2001).
These included Leschenault’s Rousette Bat Rousettus leschenaulti, Rufous
Horseshoe Bat Rhinolophus rouxi, Lesser Bamboo Bat Tylonycteris
pachypus and Hipposideros armiger (ibid.). The Lesser
Bamboo Bat was first discovered in
10.4.1.32
Two species of non-cave
dwelling bats were recorded in Tai Ho and nearby areas by AFCD (Shek and Chan
2006). These were Japanese Pipistrelle Pipistrellus abramus and
Brown Noctule Nyctalus noctula. Japanese Pipistrelle is very
common and Brown Noctule is common in
Birds inside the EBS Study Area
10.4.1.33
A total of 55 bird
species was reported in the EBS Study Area by Hong Kong Bird Watching
Society between 1993 and 1998 (Carey et al. 1998, 1999, 2001, 2002).
This included a number of rare/uncommon species (e.g., Crested Kingfisher Ceryle
lugubris) (Carey et al. 2001) and species protected by
regional/international regulation/convention (e.g., Pacific Reef Egret Egretta
sacra, Black Kite Milvus lineatus,
10.4.1.34 A total of 75 species was recorded in Tai Ho Wan during the field surveys for “Remaining Development in Tung Chung and Tai Ho Comprehensive Feasibility Study” (Mott 1998). Inter-tidal mudflat in Tai Ho Wan provides feeding habitat for a number of bird species (e.g., ardeids, kingfishers, terns, Osprey), but abundance was not high (ibid.).
10.4.1.35
A total of 118 bird species were
recorded in the EBS study area (Appendix 10A). Most of the
recorded species are common and widespread in
10.4.1.36 Bird abundance in secondary woodland, tall shrubland, shrubland-grassland mosaic and cultivated/agricultural land in the EBS study area were ranked very high. Bird abundance in wasteland and developed area were ranked high, while plantation habitat ranked low (Tables 7.1 to 7.8 in Appendix 10A).
10.4.1.37
The Project is basically
a marine project, while terrestrial habitats to be affected by this Project are
mainly developed areas on
10.4.1.38
No ardeid nesting
colony or nesting of
10.4.1.39
Black Kite, White-bellied
Sea Eagle, Osprey and Brown Fish Owl are Class 2 Protected Animals of PRC and
listed in Appendix 2 of CITES (Zheng and Wang 1998). Black Kite is common and
widespread in
10.4.1.40
Osprey and
Reptiles inside the EBS Study Area
10.4.1.41 Fourteen species of reptiles were recorded in the EBS study area (Table 5.17 in Appendix 10A). Uncommon/rare species included Blue-tailed Skink Eumeces quadrilineatus, Four-clawed Gecko Gehyra mutilata, Tokay Gecko Gekko gecko, Chinese Cobra Naja naja and Taiwan Kukri Oligodon formosanus. Locations of the sightings of these species were shown in Figure 13a of Appendix 10A.
10.4.1.42
Tokay Gecko is locally
rare and is Class 2 Protected Animal of China (Zhao 1998). It is mainly found
in thick bush and forest (Karsen et al. 1998). Chinese Cobra can be found
in many types of habitats throughout
10.4.1.43 Abundance of herpetofauna (reptiles and amphibians) was ranked high in secondary woodland, tall shrubland, shrubland-grassland mosaic and developed area, medium in wasteland and cultivated/agricultural land of the EBS study area (Tables 7.1 to 7.8 in Appendix 10A).
10.4.1.44
During the EIA study of
the Tung Chung – Ngong Ping Cable Car Project, Buff-striped Keelback was
recorded at Tung Chung (Mott 2003). This species is common and widespread in
10.4.1.45
Reptiles observed near
Tung Chung Valley area included Buff-striped Keelback Amphiesma stolata,
Large-spotted Cat Snake Boiga multimaculata , King Cobra Ophiophagus
hannah and Greater Green Snake Ophedrys major (Ridley 2001).
Buff-striped Keelback and Greater Green Snake are common in
Amphibians inside the EBS Study Area
10.4.1.46
Seven species of amphibian were recorded
within in the EBS study area (Appendix 10A). Lesser Spiny
Frog was the only species of conservation concern according to Fellowes et
al. (2002), and individuals were found in streams at two locations within
in the EBS study area (Figure 13a of Appendix 10A). This species is
the most common of the
10.4.1.47
Gunther’s Frog Rana
guentheri and Three-striped Grass Frog R. microdactyla were
recorded at abandoned cultivated land in Tai Ho Wan during the field surveys
for “Remaining Development in Tung Chung and Tai Ho Comprehensive Feasibility
Study” (Mott 1998). Both are common and widespread in
10.4.1.48
Ten amphibian species
were reported from the EBS study area by Lau and Dudgeon (1999). These
were Asian Common Toad Bufo melanostictus, Gunther’s Frog, Paddy Frog Rana
limnocharis, Three-striped Grass Frog R. macrodactyla,
Chinese Bullfrog R. rugulosa, Romer’s Tree Frog Philautus
romeri, Brown Tree Frog Polypedates megacephalus, Asiatic Painted
Frog Kaloula pulchra, Ornate Pigmy Frog Microhyla ornata and
Marbled Pigmy Frog M. pulchra. All except Chinese Bullfrog are
common and widespread in
10.4.1.49
Short-legged Toad Megophrys
brachykolos was recorded at
10.4.1.50 Romer’s Tree Frog was not recorded during the EBS study. However, several individuals and tadpoles were reported from Scenic Hill in the summer of 2004 by AFCD (Chan et al. 2005b).
Butterflies inside the EBS Study Area
10.4.1.51
Ninety species of
butterfly were recorded within the EBS study area (Table 5.16 in Appendix 10A).
Most are common and widespread in
10.4.1.52 Abundance of butterfly was ranked very high in secondary woodland, tall shrubland, shrubland-grassland mosaic, cultivated/agricultural land and developed area, high in wasteland (Tables 7.1 to 7.8 in Appendix 10A).
10.4.1.53
60 species of butterfly
were recorded at Tung Chung during the field surveys for “Remaining Development
in Tung Chung and Tai Ho Comprehensive Feasibility Study” (Mott 1998). This
included 13 uncommon and five rare species. Uncommon species included Yellow
Pansy Junonia hierta, Blue Pansy J. orithya, Plain Tiger Danaus
chrysippus, Common Cerulean Jamides celeno, Quaker Neopithecops
zalmora, Albocaerulean Udara albocaerules, Yellow Orange Tip Ixias
pyrene, Common Jay Graphium doson, Swallowtail Papilio xuthus,
Common Birdwing Troides helena, Bush Hopper Ampittia dioscorides,
Tree Flitter Hyarotis adrastus and Yellow Band Dart Potanthus parva.
Rare species included Red Lacewing Cethosia biblis, Forget-me-not Catochrysops
strabo, Painted Jezebel Delias hyparete, Common Brownie
10.4.1.54 Tree Flitter, Swallowtail, Common Jay, Bush Hopper, Plain Tiger, Yellow Band Dart, Lesser Band Dart, Common Pierrot and Yellow Orange Tip are found in abandoned cultivated lands (Bascombe et al. 1999, Yiu 2004). Red Lacewing, Yellow Pansy, Blue Pansy, Painted Jezebel, Common Birdwing, Albocaerulean, Quaker, Common Brownie and Common Cerulean are found in forest (Yiu 2004). Forget-me-not is found in low shrub and secondary growth (Bascombe et al. 1999).
10.4.1.55
A total of 40 species of
butterfly were recorded at Tai Ho Wan during the field surveys for “Remaining
Development in Tung Chung and Tai Ho Comprehensive Feasibility Study” (Mott
1998).
Dragonflies inside the EBS Study Area
10.4.1.56
Twenty-four species of
dragonfly were recorded in the EBS study area (Appendix 10A). All are common
and widespread in
10.4.1.57 Dragonfly abundance is ranked high in secondary woodland and shrubland-grassland mosaic, medium in tall shrubland, wasteland and developed area, low in cultivated/agricultural land in the EBS study area (Tables 7.1 to 7.8 in Appendix 10A).
10.4.1.58
19 species of dragonfly
were recorded at Tung Chung during the field surveys for “Remaining Development
in Tung Chung and Tai Ho Comprehensive Feasibility Study” (Mott 1998). Three
species of dragonfly were recorded at Tung Chung by
10.4.1.59 A total of 15 species of dragonfly were recorded in streams and agricultural lands in Tai Ho Wan during the field surveys for “Remaining Development in Tung Chung and Tai Ho Comprehensive Feasibility Study” (Mott 1998). Two uncommon species of damselfly were recorded at abandoned cultivated lands in Ngau Kwu Long (ibid.). These were Milky Midget Agriocnemis lacteola and Chinese Mountain Damsel Calicnemia sinensis. Milky Midget is found in abandoned cultivated lands, while Chinese Mountain Damsel inhabits small forested spate streams in low altitude (Wilson 2004).
Stream Fishes inside the EBS Study Area
10.4.1.60
Approximately 160
species of freshwater fish have been recorded in
10.4.1.61
Lowland freshwater streams
are considered one of the most endangered habitats in
10.4.1.62
Freshwater fish have
been relatively well-studied in the north Lantau area. Chong and Dudgeon (1992)
reported that the Tai Ho (46 species recorded between 1980-1991) and Tung Chung
(23 species recorded between 1980-1991) streams rank first and second in terms
of species-richness of all streams in
10.4.1.63 67 fish species were recorded during the EBS field surveys. Details are presented in the final EBS report (Appendix 10A). Survey results confirmed that the Tai Ho, Tung Chung and Sham Wat streams support high fish diversity and species of conservation interest. It should be noted, however, that only the estuaries of these three streams fall within the study area for the EBS, while the stream courses themselves are located outside the study area for the EBS.
10.4.1.64 Fish species of conservation concern recorded in the streams include the Acrossocheilus beijiangensis (in Tung Chung Stream), Anguilia marmorata (in Sham Wat Stream and Tai Ho Stream), Channa asiatica (in Pak Mong Stream, Sha Lo Stream, Sham Wat Stream, Tai Ho Stream and Tung Chung Stream), Oryzias curvinotus (in Tung Chung Stream), Plecoglossus altivelis (in Tai Ho Stream), Takifugu ocellatus (in Pak Mong Stream, San Tau Stream, Sham Wat Stream, Tai Ho Stream and Tung Chung Stream). Among these, Acrossocheilus beijiangensis, Anguilia marmorata and Oryzias curvinotus are of global concern and the remaining two species are considered locally/regionally restricted.
10.4.1.65 During the May 2004 survey, the Ayu Plecoglossus altivelis was recorded in the Tai Ho Stream. Declining populations of this species were reported locally, regionally and globally. This species is considered to be of immediate regional conservation concern (Fellowes et al., 2002) and only recorded once during the course of the surveys.
10.4.1.66
The Giant Mottled eel
Stream Invertebrates inside the EBS Study Area
10.4.1.67
The streams of
10.4.1.68 A total of twelve freshwater macroinvertebrate families/suborders consisting of 83 individuals were recorded during the EBS macroinvertebrate stream surveys conducted between September 2003 and January 2004 (Appendix 10A). The number of macrofauna species recorded in each stream was generally low except in the stream at San Shek Wan (Appendix 10A). The generally low species richness was probably caused by the lower water flow during the dry season.
10.4.1.69
It was found that the
water levels in stream courses with significant flows in wet season became much
lower in dry season, while many of the courses with low water flows in wet
season completely dried out during the dry season. This seasonal variation,
however, is typical of streams in
10.4.1.70 In order to determine the relative quality of each stream course, a BMWP (Biological Monitoring Working Party) biotic index was calculated for each stream. The BMWP biotic index for Pak Mong, Hau Hok Wan, Sha Lo Wan and San Shek Wan are 8, 0, 2 and 34, respectively. The biotic index indicated that there were large variations in the habitat quality of the streams within the study area. This, however, could be a reflection of stream flow variability and the percentage of taxa that does not have a score rather than pollution/disturbance.
10.4.2 Terrestrial Ecological Baseline within the 500m Assessment Area
Terrestrial Sites of Conservation Importance within the 500m Assessment Area
10.4.2.1
A larger portion of the
sites of conservation importance listed in Section 10.4.1 is now outside the
current 500m assessment area and far away from the HKLR footprint. Only three
of the above sites of conservation importance still fall within the current 500
m assessment area, i.e. Lantau North (Extension)
·
Lantau North
(Extension)
· San Tau Beach SSSI; and
·
The Scenic Hill on
10.4.2.2
Lantau North
(Extension)
10.4.2.3
Scenic Hill is a small
hill at the southeast end of
10.4.2.4
Before construction of
the airport, Chek Lap Kok was one of the few islands on which Romer’s Tree Frog
was found in
10.4.2.5 San Tau Beach SSSI is a seagrass site and is described in the sections on intertidal ecology below.
Vegetation and Habitats within the 500m Assessment Area
10.4.2.6
The coastal areas
between inner
10.4.2.7
The vast expanse of
terrestrial habitats (1,087 ha) between Siu Ho to Sham Wat, covering Tai Ho,
Tung Chung, San Tau, Sha Lo Wan, San Shek Wan, Airport Island and Scenic Hill,
were surveyed between September 2003 to May 2004 in the EBS.
Habitats recorded included developed area (e.g.
10.4.2.8
A large portion of the
current 500m Terrestrial Assessment Area (about 1600 ha) is currently sea area
(about 1,100 ha) (Figures 10.4a-c
& 10.5 & 10.6). Terrestrial habitats within
the elongated 500m assessment area are located in the middle to eastern parts
on
10.4.2.9
A total of 14 habitat
types were identified in the current 500m assessment area. Terrestrial
habitats recorded included woodland, shrubland, grassland, stream/channel,
plantation, and developed area (Figures 10.4a-c
& 10.5 & 10.6). Among these habitats,
developed area on
Table 10-2 Coverage of Different Habitats within the 500m Assessment Area
Habitat Type |
Area (ha) |
No. of plant species recorded |
Active Dry Agriculture |
0.05 |
NA |
Associated Mangrove |
0.80 |
20 |
Developed Area |
About 350 |
111 |
Grassland |
0.40 |
19 |
Grassland/ Shrubland |
15.22 |
96 |
Mangrove |
0.14 |
18 |
|
15.37 |
67 |
Mudflat |
0.14 |
NA |
Seasonally Wet Grassland |
0.64 |
85 |
Secondary |
17.73 |
90 |
Shrubland |
10.50 |
Included by grassland/shrubland |
Stream |
1.35 |
50 |
Tall Shrubland |
42.70 |
123 |
Young |
3.84 |
49 |
10.4.2.10 A total of 307 plant species were identified within the current 500m assessment area. Tall shrubland, secondary woodland, grassland/shrubland and developed area support higher plant species diversities, with 123, 90, 96 and 111 plant species respectively, than other coastal and riparian habitats.
10.4.2.11
Low numbers (3-5
individuals) of the tree Pavetta hongkongensis were identified in tall
shrubland close to Hau Hok Wan. This species is protected under the
Forestry Regulations (Cap. 96A) but it is a common tree species found in tall
shrubland and young woodland in
10.4.2.12
The insectivorous herb Drosera
indica was identified on the rock surface of a stream at Hau Hok Wan.
Approximately 40 individuals of D. indica were identified in both dry
and wet season surveys. This herbaceous plant is identified as a very rare
plant only found in Tung Chung (Xing et al. 2000) but receives no
protection by law in Hong Kong (South China Institute of Botany & AFCD
2003). It has been listed as “Least Concern” in
10.4.2.13
Around six individuals of
orchid Eulophia graminea were identified within the stone crevices along
a stream at Hau Hok Wan. This orchid species is a restricted terrestrial
herb found in the grassland and highly disturbed areas (Siu 2000, Xing et al.
2000). All wild native orchid species are protected under the Protection
of Endangered Species of Animals and Plants Ordinance (Cap. 586) and the
Forestry Regulations (Cap. 96A) in
10.4.2.14
Several tree specimens
and seedlings of Aquilaria sinensis were identified along the footpath
near the tall shrubland from Hau Hok Wan to Sha Lo Wan and within the secondary
woodland of the Scenic Hill in Chek Lap Kok Island. Due to potential threats of
habitat destruction and over-exploitation in
10.4.2.15
Numerous individuals of
tree Thespesia populnea were identified along the coastal and associated
mangrove habitats of the Study Area. This is a tree species restricted to
coastal habitats (Xing et al. 2000) and is regarded as a rare associate
mangrove species (present in only nine of 43 mangrove stands) in a
territory-wide mangrove study by Tam and Wong (1997). However, T. populnea has
no protection by law in
10.4.2.16
An individual of
shrub/small tree Drosera viscosa was recorded near the tall shrubland
close to the coastline at Sha Lo Wan. This is regarded as a rare species only
found in Ham Tin and Tung Chung (Xing et al. 2000), but it is not
protected by law in
10.4.2.17 Two seagrass species, Halophila sp. and Zostera japonica were recorded along the mangrove fringe within the San Tau Beach SSSI. The seagrass bed at San Tau mudflat and mangrove stands is regarded to be of high conservation value and its locality is designated as San Tau Beach SSSI for better protection by law (South China Institute of Botany & AFCD 2003). In addition, all established seagrass beds are considered to be an important habitat under the Environmental Impact Assessment Ordinances and any potential developmental disturbances and/or impacts should be avoided or minimized (Kwok et al. 2005).
10.4.2.18 Three natural habitats are of particular concerns, i.e. the young woodland in Sha Lo Wan headland, on which the viaduct will span over, the grassland/shrubland habitat on Scenic Hill where direct impact from the latest alignment is anticipated, and the secondary woodland on Scenic Hill, where remnant population of Romer’s Tree Frog was recorded previously and is potentially subject to direct impacts under some earlier alignment options.
10.4.2.19 The headland at Sha Lo Wan is young woodland habitat. Under natural succession, this young woodland has evolved from tall shrubland by developing a denser and more complex canopy coverage and structure. The young woodland is dominated by the trees Sterculia lanceolata, Microcos paniculata, Ardisia quinquegona, Myrsine seguinii, Schefflera heptaphylla and Garcinia oblongifolia, with the understorey containing shrubs such as Psychotria asiatica, Desmos chinensis, Ardisia crenata, Ilex asprella, Ilex pubescens and seedlings of tree species including Daphniphyllum calycinum, Archidendron clypearia and Archidendron lucidum.
10.4.2.20
The majority of the
grassland/shrubland habitat within the 500m Assessment Area is on North Lantau,
and typically dominated by grasses Panicum maximum, Imperata koenigii,
Ischaemum spp., Rhynchelytrum repens and Neyraudia reynaudiana,
herbs Bidens alba, Eupatorium catarium, Mimosa pudica, Aster
baccharoides, Inula cappa, isolated shrubs Melastoma candidum,
Rhaphiolepis indica, Rhodomyrtus tomentosa, Ilex asprella,
Osbeckia chinensis, Clerodendrum fortunatum, Baeckea
frutescens, Breynia fruticosa and Eurya chinensis and trees Zanthoxylum
avicennae, Litsea rotundifolia var. oblongifolia, Schefflera
heptaphylla, Aporusa dioica, Ficus hirta, Ficus variolosa
and Itea chinensis. The grassland/shrubland habitat on
10.4.2.21 Besides the above, there were also intertidal habitats (including artificial seawall, natural shore, mangrove and intertidal mudflat), marine waters, and other terrestrial habitats (agricultural land) recorded within the 500m boundary or inside Tai Ho area. These habitats would be covered in the later sections on intertidal ecology, marine ecology, and Tai Ho area.
Terrestrial Fauna within the 500m Assessment Area
10.4.2.22
The surveyed terrestrial
habitats within the 500m Assessment Area were urbanised/disturbed (including
artificial coastlines), stream/channel, woodland, grassland, and shrubland. The
recorded fauna were typical of disturbance tolerant, due to the high
disturbance level within the Assessment Area. More than 60% of the terrestrial
habitats within the 500m Assessment Area are Developed Area, which is under
high level of human disturbance. Grassland/shrubland made up 4.55% of total
area of terrestrial habitats. Fauna diversity in this type of habitat is
generally low (Dudgeon and Corlett 1994, 2004). Plantations of exotic
species made up only 4.59% of total area of terrestrial habitats. This type of
habitat, particularly young ones, generally supports low fauna diversity (Dudgeon
and Corlett 1994, 2004).
Birds within the 500m Assessment Area
10.4.2.23
A total of 77 species
was reported from Chek Lap Kok airport (Carey et al. 1998, 1999, 2002).
This high species richness was at least partially attributed to the fact that
birds are more visible at the airport, but does not indicate the ecological
importance of the Chek Lap Kok airport as a bird habitat. A total of 136 bird
species was recorded in the
10.4.2.24 Use of inter-tidal mudflats near San Tau by ardeids (e.g., Reef Egret, Little Egret) was reported in the EIA study of the Tung Chung – Ngong Ping Cable Car Project (Mott 2003).
10.4.2.25 A total of 61 bird species was recorded during the EVS study. Of these 61 species, 14 are listed by Fellowes et al. (2002) as species of conservation concern; 10 of the 14 species of conservation concern are also wetland dependant species, and were observed on the shoreline of northern Lantau and the artificial seawall of Chek Lap Kok. These species included Grey Heron, Great Egret, Little Egret, Pacific Reef Egret, Straited Heron, Black-crowned Night Heron, Little Ringed Plover, Whimbrel, and Grey-tailed Tattler. Birds utilizing coastal habitats should be of higher concern in the present Project as the majority of terrestrial habitats to be affected are the coastal areas along the Airport Channel and Airport eastern shore.
10.4.2.26
Apart from Pacific Reef
Egret, all are common and widespread in
10.4.2.27 Bird species that are locally rare or regional/global protected were considered of conservation concern. Among the water-dependent birds, only Pacific Reef Egret Egretta garzetta is Class 2 Protected Animals of PRC (Zheng and Wang 1998). Pacific Reef Egret is mainly found in rocky coastlines of widespread localities (Carey et al. 2001).
Mammals within the 500m Assessment Area
10.4.2.28 During the EIA study of the Tung Chung – Ngong Ping Cable Car Project, Indian Muntjac was observed in tall coastal shrub/ woodland off the coastal path near Hau Hok Wan in May 2002, and in woodland of the San Tau Valley and Ngau Au Area in early October 2002 (Mott 2003). Scats of Ferret Badger or civet were found near San Tau Valley (ibid.). Indian Muntjacs were recorded in tall shrubland of Sha Lo Wan in September 2003 and April 2004 during the EBS study. The common rat Rattus norvegicus was observed around San Tau village during the course of the survey during the field surveys for the EIA of Tung Chung Cable Car Project (Mott 2003).
10.4.2.29
Only three species of
mammal were recorded during the EVS study. A Red Muntjac Muntiacus
muntjac was seen in the village section of San Tau stream. In
addition, footprints of Muntjac deer, presumably Red Muntjac, were observed in
the soft sand at the beach close to the mouth of a stream at San Tau. Red
Muntjac (as Indian Muntjac) is listed as being of Potential Regional Concern
following Fellowes et al. (2002) and is protected under the Wild Animals
Protection Ordinance (WAPO). This small deer is widespread in
10.4.2.30
The skull of a Eurasian
Wild Pig Sus scrofa was found on the beach at Sha Lo Wan. This species
has a widespread distribution in
10.4.2.31
Four species of
non-cave dwelling bats were recorded in San Tau and nearby areas by AFCD (Shek
and Chan 2006). These were Japanese Pipistrelle Pipistrellus abramus,
Short-nosed Fruit Bat Cynopterus sphinx, Lesser Yellow Bat Scoptophilus
kuhlii and Whiskered Myotis Myotis muricola. Both Japanese
Pipistrelle and Short-nosed Fruit Bat are very common in
Reptiles within the 500m Assessment Area
10.4.2.32
Seven species of reptiles, all common and
widespread in
10.4.2.33
During the EIA study of
the Tung Chung – Ngong Ping Cable Car Project, Long-tailed Skink Mabuya
longicaudata and Copperhead Racer Elaphe radiata were recorded in
San Tau (Mott 2003). Both are common and widespread in
10.4.2.34
Checkered Keelback Xenochrophis
piscator was recorded at mangroves near San Tau (Mott 1998). This species
is common and widespread in lowland wetlands in
10.4.2.35
Two species of snakes
were reported from the Airport island (Chan et al. 2006a). These
were Large-spotted Cat Sanke Boiga multomaculata and Chinese Cobra Naja
atra. Both are common and widespread in
10.4.2.36
Chinese Gecko Gekko
chinensis and Bowring’s Gecko Hemidactylus bowringii were reported
from the Airport island and San Tau respectively (Chan et al.
2006b). Both species are very common in
Amphibians within the 500m Assessment Area
10.4.2.37
Four species of amphibians were recorded
during the EVS in the 500m Assessment Area (Appendix 10B), Chinese Bullfrog
Hoplobatrachus chinensis, Lesser Spiny Frog Paa exilispinosa,
Asian Common Toad Bufo melanostictus and Asian Painted Frog Kaloula
pulchra. Chinese Bullfrog is a Class II Protected Animal in
10.4.2.38
Tadpoles of Lesser
Spiny Frog were observed in the streams between San Tau and Hau Hok Wan.
This species is regarded as Vulnerable by IUCN Redlist (2009) and is
considered to be of Global Concern (Fellowes et al. 2002), although it
is widely distributed and common in suitable habitat in
10.4.2.39
Romer’s Tree Frog was
not recorded during the EBS study or the EVS study. The endemic
Romer’s Tree Frog was discovered on
10.4.2.40 Prior to the construction of Chek Lap Kok International Airport, populations of Romer’s Tree Frog on Chek Lap Kok were collected, captive bred and translocated to localities with suitable local habitats (Lau 1998) as a mitigation measure for the PADS project. Breeding of translocated populations was monitored between 1994 and 1997 (ibid.). Regular breeding was recorded at half of the translocated sites (ibid.).
10.4.2.41 While it was believed that the population on Chek Lap Kok would be exterminated by the construction of the new airport, a single specimen was caught at the abandoned village on the south side of the former island in July 2000 (Lynch 2001). The presence of old water tubs and pitchers maintain pools of rain water, which provide breeding habitats for Romer’s Tree Frog. This enabled survival of a small population.
10.4.2.42
Indeed Romer’s Tree
Frog has demonstrated a high adaptability elsewhere in
10.4.2.43
Besides the EBS
study and the EVS study, night survey conducted for Cable Car EIA study
at Scenic Hill aimed at verifying Lynch’s finding also failed to find any
evidence of Romer’s Tree Frog (Mott 2003). The general environment and
topography of Scenic Hill have not changed significantly since the discovery of
the frog in 2000. Breeding habitat of Romer’s Tree Frog is also present on
Scenic Hill (e.g., streams, old water tubs and pitchers). Tadpoles of
this species were seen earlier in 2008 as part of the on-going monitoring by
AFCD (Appendix 10B).
Therefore it is reasonable to adopt a precautionary approach assuming that some
individuals still survive in the area. This makes Scenic Hill the only location
on
10.4.2.44
Some amphibian species
were recorded in the Airport island by AFCD (Chan et al. 2005b).
These included Asian Common Toad Bufo melanostictus, Short-legged Toad Xenophrys
brachykolos, Asiatic Painted Frog Kaloula pulchra,
Dragonflies within the 500m Assessment Area
10.4.2.45 A common damselfly species Marsh Dancer Onychargia atrocyana was reported in Sha Lo Wan (Wilson 2004). This species occurs in wet abandoned cultivated lands (ibid.).
10.4.2.46 The dragonfly species, Small Hooktail Melliogomphus moluamis, which is considered globally threatened by Fellowes et al. (2002) was recorded at San Tau during the EBS (Appendix 10A). Very little is known about the habitat requirements of this species (Wilson 2004).
10.4.2.47
Only seven dragonfly
species were recorded during the EVS study, none of which are considered
to be of conservation concern. By far the most numerous and widespread
species recorded was the Wandering Glider Pantala flavescens, with many
hundreds seen across the site over all habitats. This is the most common
species in
Butterflies within the 500m Assessment Area
10.4.2.48 Danaid Eggfly Hypolimnas misippus, considered of conservation concern according to Fellowes et al. (2002), was found in shrubby-grassland in Scenic Hill during the EBS study.
10.4.2.49
A total of 58 butterfly
species was recorded during the EVS study. Most species occur in
shrubland (32) with 24 species recorded in woodland and 15 species recorded
from village habitats. Few records of butterflies were made from the intertidal
habitats (i.e. soft shore, hard shore and mangrove), as would be expected from
the paucity of suitable food plants in this habitat. Common Mormon Papilio
polytes was the most widespread species, occurring in various habitat
types. This species is very common and widespread in
10.4.2.50 The hillside along the coastline from Tung Chung to Tai O is a recommended butterfly watching route by the Lepidopterist’s Society (Young and Yiu 2002). Rare species such as Hainan Palm Dart Telicota besta and Common Awl Hasora badra are reported from this trail (ibid.).
10.4.2.51
Two locations within
the Study Area – San Tau and Sha Lo Wan – have been identified as important
sites for butterflies in
10.4.2.52 A total of 89 species of butterfly have been recorded in San Tau (Yiu 2004). Uncommon/rare butterfly species reported in this location include Golden Birdwing Troides aeacus, White Dragontail Lamproptera curius, Plain Cupid Chilades pandava, Falcate Oak Blue Mahathala ameria, Red Lacewing, White-edged Blue Baron Euthalia phemius (ibid.). Important butterfly habitats identified in San Tau include ravine woodland, fung shui forest and orchard (ibid.).
10.4.2.53 A total of 81 species of butterfly have been recorded in Sha Lo Wan (Yiu 2004). Uncommon/rare butterfly species reported in this location included Swallowtail, Red Lacewing, Yellow Orange Tip, Cornelian Deudorix epijarbus, Silver Streak Blue Iraota timoleon, Dark Blue Tiger Tirumala septentrions (ibid.). Important butterfly habitats in Sha Lo Wan include fung shui forest and abandoned cultivated land (ibid.).
Stream Fish within the 500m Assessment Area
10.4.2.54 Several species of conservation interest were recorded in streams within the 500m assessment area, including Beijiang Thick-lipped Barb Acrossocheilus beijiangensis, Dark-margined Flagtail Kuhlia marginata, Rice Fish Oryzias curvinotus, the Indo-Pacific Tropical Sand Goby Favonigobius reichei.
10.4.2.55
Beijiang Thick-lipped
Barb is a rare species and only appears in several locations including streams
on
10.4.2.56 Dark-margined Flagtail Kuhlia marginata was observed at the same stream. This species was regarded as locally endangered in a recent EIA Study Report (DSD 2005). It is regarded to be of Regional Concern by Fellowes et al. (2002), but its status was not evaluated by Lee et al. (2004) or AFCD (2009). Since freshwater streams are important nursery habitats for this catadromous species (Oka & Tachihara 2008), ST9 is considered to have potential to be a nursery habitat for this species.
10.4.2.57
Rice Fish Oryzias
curvinotus was found at three stream sites and is a species considered to
be of Global Concern (Fellowes et al. 2002) which is uncommon in the
wild in Hong Kong (Lee et al. 2004). Although it is generally considered
to be a freshwater species, it can inhabit brackish environments (Froses &
Pauly 2008) and a large population was seen in the mangrove area of
10.4.2.58
Predaceous Chub Parazacco
spilurus is common and widespread in Hong Kong (Lee et al. 2004), but is
regarded as a vulnerable species in Mainland
10.4.2.59
Populations of over 100
individuals of this species were seen in the middle sections of ST9 and
SL3. The Indo-Pacific Tropical Sand Goby Favonigobius reichei, which is
regarded as “Lower Risk/ Near Threatened” by IUCN (2009), was found in the
lower sections of several streams surveyed. Whilst it is regarded
globally as Near Threatened, this species is common and widespread in the
intertidal area in
Stream Invertebrates within the 500m Assessment Area
10.4.2.60
The Sesarmine Crab
species Chiromantes sereni was found in the lower sections of HH3 and
SL3. This species was first recorded in
10.4.2.61 Somanniathelphusa zanklon, another endemic crab species, was also found in the Current Study. Although this species has been found to be quite abundant in Lantau and other places in Hong Kong (DSD 2002, EPD 2007), it is regarded as an endangered species by IUCN due to its restricted distribution (IUCN Redlist 2009). Two juveniles of this species were recorded in ST12. This small stream has potential to provide a nursery habitat for this endangered species.
10.4.2.62
Greasyback Shrimp Metapenaeus
ensis juveniles were recorded in the lower section of the streams ST9 and
SL3. Shrimps belonging to the genus Metapenaeus are commercially important and
were extensively cultured in the Gei Wai of Mai Po in the past. They are
common in mangrove and estuarine areas in
10.4.3 Marine and Intertidal Ecological Baseline
Marine Recognized Sites of Conservation Importance and important habitats
10.4.3.1 Recognised Sites of Conservation Importance at intertidal zone are divided into two groups, i.e. those within the North Western and North Western Supplementary WCZs, and those within the marine ecological assessment area for the EIA Study.
Within the North Western and North Western Supplementary Water Control Zones
10.4.3.2 There are several Recognised Sites of Conservation Importance and important habitats located Within the North Western Water Control Zone:
· Site of Special Scientific Interest (SSSI) at San Tau Beach;
·
Horseshoe crab nursery
sites at Sham Wat, Hau Hok Wan, San Tau,
· Tai Ho Stream SSSI;
· Seagrass site at Yam O;
· Artificial reefs;
· Sha Chau and Lung Kwu Chau Marine Park;
· The proposed Marine Park at Fan Lau; and
· Marine waters in North and West Lantau waters as dolphin habitats (in particular dolphin hotspots).
Within the Marine Ecological Assessment Area of the EIA Study
10.4.3.3 There are further Recognised Sites of Conservation Importance and important habitats located at intertidal and subtidal zones within the marine ecological assessment area as follows:
·
The proposed Marine
Park at
·
Horseshoe crab nursery
site at Shui Hau: Shui Hau, which is the third identified horseshoe crab
nursery sites in
·
Pak Nai SSSI: Pak Nai
SSSI was designated in 1980 for its function as roost site for gulls and terns
in the
· Seagrass beds and Horseshoe crab nursery site in Pak Nai: Pak Nai is one of the three confirmed horseshoe crab nursery site (Chiu and Morton 1999) and also harbours the largest seagrass beds in Hong Kong (Fong 1998);
·
Mai Po and
· Inner Deep Bay SSSI; and
· Tsim Bei Tsui SSSI.
10.4.3.4
The coastal areas of
the southeast shore of
10.4.3.5
In addition to the
above recognised sites, another SSSI, i.e. The Lung Kwu Chau,
San Tau Beach SSSI
10.4.3.6
Tung Chung Bay is the
largest lowland and river mouth habitat on North Lantau, as well as within the
marine ecological assessment area except inner
Horseshoe
Crabs and Horseshoe Crab Nursery Sites at Sham Wat, Hau Hok Wan, San Tau,
10.4.3.7
Horseshoe crabs are an
ancient and taxonomically isolated group (class Merostomata, sub-class
Xiphosura) related to spiders, ticks and mites. Though not presently protected
under local law, Horseshoe crabs have been identified as a species of
conservation importance in
10.4.3.8
In an extensive study
of the distribution of horseshoe crabs in
10.4.3.9
Horseshoe crabs, most
commonly T. tridentatus, have been recorded in the HKSAR at Tap Shek
Kok, Sha Chau, Tai Po and Peng Chau, though there are no recent records from
any of these sites (Huang 1997). C. rotundicauda was recorded in 1997
from Ma Wan Chung, Lantau, at a site that would be lost to development of the
Tung Chung New Town (ibid.). The other areas where horseshoe crabs have
been recorded in the HKSAR are on the shores of
10.4.3.10
Horseshoe crabs are
currently more often found in western waters of Hong Kong, though they were
once thrived on many beaches in Hong Kong including
10.4.3.11 During the Crosslinks 2 study, horseshoe crabs were reported to have been recorded from trawl surveys at Tap Shek Kok, and beaches at Lung Kwu Sheung Tan and Lung Kwu Tan were thought once to be breeding grounds for horseshoe crabs, based upon information from the residents in Lung Kwu Tan (Mouchel 1999). It was also reported that spawning of horseshoe crabs was seen in Lung Kwu Sheung Tan many years ago (Huang et al. 1999).
10.4.3.12 Confirmed nursery sites for horseshoe crabs in recent years included Pak Nai, San Tau and Shui Hau (Huang et al. 1999), together with Tai Ho Wan (Fong 1999). Some other beaches on Lantau, including Tai O, Yi O, Sham Wat Wan, Sha Lo Wan and Tung Chung, are considered of high possibility due to the records that adult horseshoe crabs were frequently fished offshore (Huang et al. 1999).
10.4.3.13
At a territory-wide
study, three locations, i.e. Pak Nai in
10.4.3.14 Two species of horseshoe crab, Tachypleus gigas and Tachypleus tridentatus, have been recorded from trawl surveys at Tap Shek Kok just south of Lung Kwu Tan, and the beaches at Lung Kwu Sheung Tan and Lung Kwu Tan have been identified as potential breeding sites for T. gigas (ERL 1993, ERM 1996). Juvenile horseshoe crabs are seen by fishermen in the intertidal zone from Sheung Pak Nai to Ngau Hom Shek, but adults are seldom seen.
10.4.3.15
In Deep Bay the
preferred habitat was identified as sandy to muddy intertidal zones, which
appear to provide habitats for mating and egg laying, and for juveniles.
Currently, Ha Pak Nai in
10.4.3.16 T. tridentatus and C. rotundicauda have been recorded at Tai Ho Wan, Tung Chung Wan, San Tau and Sha Lo Wan and Sham Wat (Huang 1997; Chiu and Morton 1999; Fong 1999; Mouchel 2000 2002c; Mott 2003). Specimens of horseshoe crabs were also collected in north Lantau waters (ERM 1997; Chiu and Morton 1999).
Tai Ho Stream SSSI
10.4.3.17
The Tai Ho Stream SSSI
is about 5ha in area and comprises two main components: Tai Ho Stream and the
inner part of Tai Ho Wan. "Tai Ho Stream" includes several
tributaries that lie to the south and east of Tai Ho Wan, passing Tin Liu, Tai
Ho San Tsuen, and merging just below Ngau Kwu Long, and entering Tai Ho Wan at
its southern end. Tai Ho Stream is one of the most ecologically valuable
fresh water streams in
10.4.3.18 The importance of Tai Ho Stream to Hong Kong's freshwater fish fauna, and the linkages to other ecologically important intertidal habitats in Tai Ho Wan, qualify Tai Ho Stream as a habitat of high ecological value. Conservation and prevention of damage to the stream channel and riparian zone is essential. The Tai Ho Stream and part of its estuarine zone were designated as an SSSI in 1999 in recognition of the ecological importance of the stream and its fish fauna.
Seagrass site at Yam O
10.4.3.19
Seagrasses were
recorded in Yam O (
Artificial Reefs
10.4.3.20 Artificial
Reefs were deployed near the northeast corner of Airport Island within Marine
Exclusion Zone 3 and at Sha Chau and Lung Kwu Chau Marine Park. Both ARs
were deployed in 2000, with a footprint of 1,200 m2 (3,600 m3
in terms of volume) in the Marine Exclusion Zone, and a footprint of 3,660 m2
(3,600 m3 in terms of volume) in the
Sha
Chau and Lung Kwu Chau Marine Park
10.4.3.21
North Lantau waters
also contain Sha Chau and
Proposed
10.4.3.22
The waters off the southwest coast of
Lantau (i.e. Fan Lau) is considered a proposed
10.4.3.23
West Lantau and North
Lantau waters which are the most important dolphin habitats in Hong Kong.
Chinese White Dolphin is present commonly year-round in the waters north and
west of Lantau, and are found only seasonally or rarely in other places of
Other recognized sites of conservation importance/ important habitats
10.4.3.24
The proposed
10.4.3.25
Horseshoe crab nursery
site at Shui Hau: Shui Hau, which is the third identified horseshoe crab
nursery sites in
10.4.3.26
Pak Nai SSSI was
designated in 1980 for its function as roost site for gulls and terns in the
10.4.3.27
Seagrass beds and
Horseshoe crab nursery site in Pak Nai: Pak Nai is one of the three confirmed
horseshoe crab nursery site (Chiu and Morton 1999) and also harbours the
largest seagrass beds in
10.4.3.28
Mai Po and Inner Deep
Bay Ramsar Site is the only Ramsar Site in
10.4.3.29
Inner Deep Bay SSSI is
designated in 1986. It covers 2,300 ha of intertidal mudflats and
mangroves at the inner most part of inner
10.4.3.30
Tsim Bei Tsui SSSI is also
located in inner
Intertidal Ecological Baseline for the North Western Water Control Zone
10.4.3.31
Similar with the
terrestrial habitats, intertidal habitats relevant to the ecological impact
assessment are located in two main areas, i.e. the North Lantau coastlines near
the Airport Channel and the shores on
10.4.3.32 The North Lantau coastlines near the Airport Channel are mainly natural intertidal habitats, including undisturbed rocky shores and intertidal sandflats/mudflats, while all the original coastlines in Tung Chung New Town (the eastern end of the present project’s study area) have been lost to reclamation.
10.4.3.33
The coastlines of
Artificial Seawalls
10.4.3.34 The dominant intertidal habitat type within the 500m distance of the HKLR alignment was sloping boulder-form artificial seawall.
10.4.3.35
All the coastlines on
the southern
10.4.3.36
The intertidal habitats on the
artificial seawalls of
10.4.3.37
The sloping seawalls in
the Northeast of Airport Island, where direct impacts on intertidal zone from
the HKBCF reclamation are anticipated, were also surveyed during the HKBCF
ecological survey programme. The artificial seawalls were colonised
by intertidal fauna, but the abundance and diversity were low. The species
recorded were all common in
Rocky Shores
10.4.3.38 The remaining intertidal habitats within the 500m assessment area of the HKLR, except those inside embayments as explained in the next section, are rocky shores including 1) remnant rocky shores along the southeast coast and a small section at the northeast end of Airport Island, and 2) undisturbed natural rocky shores on North Lantau coastlines from Tung Chung Bay to Sham Wat.
10.4.3.39
Rocky shores are not
rare in
10.4.3.40 During the intertidal survey for the EBS between September 2003 to May 2004, all recorded species on hard intertidal shore are common and widespread in Hong Kong, such as rock oyster Saccostrea cucullata and littorinid gastropod Littoraria articulata.
10.4.3.41
Their survey results
revealed that only common intertidal species such as freshwater nerite (Clithon
cf. faba), top shell (Monodonta labio), nerite (Nerita spp.),
rock oyster (Saccostrea cucullata), the littorinid gastropod (Littoraria
articulata and Nodilittorina radiata), common whelk (Thais clavigera),
and acorn barnacle (Balanus sp.) were recorded on the rocky shores. In
addition, a few small shore crabs (Hemigrapsus sanguineus) and one
hermit crab were seen on pebbles or rocky bottom. All hard-bottom intertidal
species recorded are common and characteristic of intertidal habitats
throughout
10.4.3.42
The undisturbed natural
coastlines on
10.4.3.43
The remnant coastlines
at the southeast shore of Airport Island, which are originated from the old
Chek Lap Kok Island, were surveyed during the Marine Supplementary Survey (MSS)
for the HKLR. Four locations were investigated following the same hard
shore methodology applied in the EVS and the HKBCF survey
programme. Although not being completely converted to artificial
coastlines, these coastlines have been subject to disturbance and modification
of various extents, including the elimination of backshores and conversion to
seawalls, and thus should not be considered as natural coastlines. It was
also isolated from other natural shores. Only 26 taxa were recorded from
both quantitative and wall-through survey during wet and dry seasons. All
the species found are common and widespread intertidal fauna in
Intertidal Sandflats/Mudflats
10.4.3.44
The intertidal habitats
from
10.4.3.45
Intertidal mudflats,
together with the mangroves and seagrasses, were found to be the most
ecologically important intertidal habitats for the present EIA.
Ecological functions provided by these communities include energy cycling,
coastal stabilisation, and habitat for wildlife such as coastal birds and
horseshoe crabs.
10.4.3.46 Important species such as horseshoe crabs and seagrasses are present within certain intertidal sandflats/mudflats in the study area (ERM 2001; Mouchel, 2000, 2002b; Tam and Wong, 2000; Mott, 2003).
10.4.3.47
During the EBS
study, soft shores were surveyed, and quantitative transect survey were
performed in selected locations including
10.4.3.48 In the EVS study, six soft shore locations (Sham Wat (SW), Sha Lo Wan (SLW), Hau Hok Wan (HHW), Tung Chung Bay (TCB), San Tau (ST) and San Shek Wan (SSW)) along the northern coast of Lantau (The locations of these soft shore locations are shown in Appendix 10B) were surveyed to cover wet and dry seasons.
10.4.3.49 A total of 155 species from several faunal groups, including echinoderms (sea cucumber), arthropods (shrimp, crab and horseshoe crab), molluscs (bivalve, gastropod and tusk shell), annelids (segmented worm), sipunculids (peanut worm), nemerteans (ribbon worm), cnidarians (sea anemone) and poriferans (sponge), were recorded from these soft shore sites. Of these six sites, the highest species number was recorded at San Tau and Tung Chung B ay (76), and the lowest number was recorded at Sham Wat (57). Species numbers recorded at San Shek Wan, Sha Lo Wan and Hau Hok Wan were 69, 72 and 75, respectively.
10.4.3.50 During the transect and quadrat surveys, a total of 26,627 individuals belonging to 104 species were recorded, including a single horseshoe crab individual. A total of 1,019 individuals belonging to 56 fauna species were found in the core samples. Findings of quantitative surveys are summarized in the table below.
Table 10-3 Species
number, numerical abundance, Pielou's evenness index (J’) and
|
SW |
SSW |
SLW |
HHW |
ST |
TCB |
Epifauna |
||||||
Number of Species |
29 |
42 |
44 |
49 |
55 |
50 |
Abundance |
1259 |
4147 |
5079 |
3899 |
4222 |
8021 |
J’ |
0.46 |
0.49 |
0.47 |
0.53 |
0.55 |
0.43 |
H’ (Log e) |
1.56 |
1.82 |
1.79 |
2.07 |
2.20 |
1.67 |
Infauna |
||||||
Number of Species |
12 |
20 |
17 |
18 |
19 |
24 |
Abundance |
164 |
265 |
83 |
56 |
115 |
336 |
J’ |
0.45 |
0.52 |
0.74 |
0.86 |
0.81 |
0.48 |
H’ (Log e) |
1.11 |
1.56 |
2.10 |
2.47 |
2.38 |
1.51 |
10.4.3.51 Most species found during these surveys are common and widespread in Hong Kong. Six species considered of international or regional (China) conservation importance were recorded (Table 10-4), details of which are given in the following paragraphs.
Table 10-4 Species of international or regional conservation importance found in soft shore habitats
Species |
SW |
SSW |
SLW |
HHW |
ST |
TCB |
Indo-Pacific Tropical Sand Goby Favonigobius reichei |
+ |
+ |
+ |
+ |
+ |
+ |
Snowy Puffer Takifugu niphobles |
|
|
|
+ |
+ |
|
Predaceous Chub Parazacco spilurus |
|
+ |
|
|
|
|
Sea Cucumber Holothuria leucospilota |
+ |
|
|
|
|
|
Horseshoe Crab Tachypleus tridentatus |
+ |
|
|
|
+ |
+ |
Greasyback Shrimp Metapenaeus ensis |
+ |
|
+ |
+ |
+ |
|
10.4.3.52 The Indo-Pacific Tropical Sand Goby Favonigobius reichei, which has been regarded as “Lower Risk/Near Threatened” by IUCN (2009), was found to be very common at all the study sites. Although it is regarded globally as Lower Risk/Near Threatened, this species is common and widespread in intertidal areas in Hong Kong (Lee et al. 2004, Nip 2005).
10.4.3.53 Another fish species observed, Snowy Puffer Takifugu niphobles, is regarded as “Data Deficient” by IUCN (2009). This fish is, however, considered to be common in Hong Kong (Nip 2005, AFCD 2009b).
10.4.3.54 Two Predaceous Chub Parazacco spilurus were observed in a freshwater creek running across the shore in SSW. This species is considered to be Vulnerable in Mainland China (Yue & Chen 1998, CSIS 2008). This is primarily a freshwater species, however, and is not known to tolerate saline conditions; its presence on the surveys probably resulted from upstream populations having been washed into the lower reaches of the stream.
10.4.3.55 The Horseshoe Crab Tachypleus tridentatus was recorded at two of the soft shore sites, TCB and ST. Two records from TCB included a juvenile (max. width of prosoma = 40mm) and one dead subadult (max. width of prosoma = 150mm). The single crab at ST was one tiny juvenile (max. width of prosoma = 5mm). This Horseshoe Crab species is regarded as Vulnerable by CSIS (2008).
10.4.3.56 The Sea Cucumber Holothuria leucospilota was found on the shore of SW. This species is usually found in the low tide/subtidal zone of boulder shores (Morton & Morton 1983) and the soft shore at SW is not optimal habitat for this species. It is the most common holothuroid in Hong Kong (Lai et al. 2006) but is regarded as Endangered in Mainland China due to over-exploitation (CSIS 2008).
10.4.3.57 Although Metapenaeus spp. are common in mangrove and estuarine areas in Hong Kong (Leung 1999, Vance 1999), all four species found in Hong Kong (including M. ensis) are considered to be Vulnerable in Mainland China due to over-exploitation (CSIS 2009). In the Current Study, individuals of M. ensis were found in SW, SLW, HHW and ST.
10.4.3.58 All of the species recorded were typical soft shore intertidal fauna and can be found in similar habitats throughout Hong Kong. Mud snails (Cerithidea diadjariensis) were common representatives on the sand-flats of Tung Chung Bay. Survey results obtained at Tai Ho Wan also revealed that the mud snail (C. diadjariensis) was dominant. Common species including acorn barnacle (Balanus sp.), small shore crab (Hemigrapsus sanguineus) and the nerite (Nerita polita) were abundant on hard surfaces such as rocks and boulders present on the soft shores of the entire coastal study area. Species abundance was similar in wet and dry seasons. Besides the sandflats/mudflats, there are some patchy sandy beaches on the southeast shore of Airport Island. These patcthy sandy beaches are of very low abundance of intertidal fauna as recorded during the MSS, and no infauna was recorded in the sediment in these sandy beaches (see Appendix 10C).
10.4.3.59 Tai Ho Wan is located in the estuarine area and harbours intertidal mudflats and mangroves. It has been partly cut off from the sea by the construction of the North Lantau Highway. A culvert at the western end of the bay maintains tidal exchange within the bay. The southern end of the bay is dominated by mangroves and extensive mudflats where Tai Ho Stream enters the bay. Mudflats of this size are uncommon outside Deep Bay area and are becoming more and more scarce in the territory.
10.4.3.60 The intertidal habitats inside the embayment at Tai Ho Wan are dominated by intertidal mudflats, with patches of seagrass beds and mangroves along the coastline.
10.4.3.61 Intertidal mudflats, together with the mangroves and seagrasses, were ecologically important intertidal habitats. Ecological functions provided by these communities include energy cycling, coastal stabilisation, and habitat for wildlife such as coastal birds. Tai Ho Wan has extensive mudflats. Mudflats are important not only because they provide a habitat to infauna which are in turn the prey items of many waterfowls, but also they are the suitable substrate for the colonization of mangroves and seagrasses, both are important habitat types in Hong Kong. The seagrass beds are also an important nursery and feeding ground of horseshoe crabs (Fong 1999). AFCD recorded 20 C. rotundicauda individuals at Tai Ho Wan December 2003 (Appendix 10A). The structures of the mudflat habitat would be diversified by the colonizing vegetation. A large variety of microhabitat types may contribute to a diverse intertidal fauna. The high species richness of crabs in Mai Po, where 32 species of crabs were recorded, was also attributed to the large variety of microhabitats there (Lee & Leung 1999).
10.4.3.62 Tai Ho Wan provides an ecological linkage between marine habitats and freshwater habitats (Tai Ho Stream) of conservation importance. It is a movement corridor for anadromous and catadromous fishes moving between streams and the sea. The bay also provides additional habitat for the marine vagrant fish species recorded in Tai Ho Stream.
10.4.3.63 The Tai Ho area is notable for the fact that the hydrological system of streams, estuary and bay remains intact and little modified by human activity. Horseshoe crabs are known to prefer undisturbed beaches (Botton et al. 1998 in Chiu and Morton 1999). Chong and Dudgeon (1992) attributed the exceptional fish fauna they recorded in Tai Ho Stream to the relatively unaltered condition of the area. Tai Ho provides an example of a well-interlinked ecological landscape, dominated by sheltered bay, wetlands, woodlands and streams, that support a high diversity of plant and animal communities.
Mangrove Habitats
10.4.3.64 Mangrove communities are under threat from urbanisation and reclamation, and because many stands have been destroyed in Hong Kong they are considered to be a conservation priority (Tam and Wong, 2000). There is a large body of data on the mangal and seagrass habitats present in the EBS study area (e.g., Mouchel 2000; Tam and Wong 2000).
10.4.3.65 During the EBS study, mangroves in San Tau to Tung Chung Bay were surveyed. The Tung Chung and San Tau mangrove habitats have also been well studied previously (Tam and Wong 2000; Mott 2003). The mangrove habitat at San Tau is considered to be of particular ecological importance because of its size and seagrass beds. This habitat is dominated by the mangroves Aeigceras corniculatum, Kandelia candel and Bruguiera gymnorrhiza (which was previously thought to be rare but is now considered locally uncommon). Other mangroves Avicennia marina and Acanthus ilicifolius are also well represented.
10.4.3.66 During the EVS, mangrove was identified within the San Tau Beach SSSI, while two patches of associated mangrove were found along the coastlines of Tin Sam (just to the north of San Tau) and Hau Hok Wan. The mangrove habitat is dominated by a number of mangrove species, especially Aegiceras corniculatum, Avicennia marina, Bruguiera gymnorrhiza, Kandelia obovata and Acanthus ilicifolius. The associated mangrove habitats are dominated by herb Limonium sinense, shrubs Clerodendrum inerme, Suaeda australis, Scaevola sericea and Pandanus tectorius and trees Cerbera manghas, Hibiscus tiliaceus and Thespesia populnea.
10.4.3.67 There are also mangroves in Tai Ho Wan and Sham Wat. Mangroves in Sham Wat were also surveyed during the EBS, and different from the mangrove stands in Tung Chung Bay or Tai Ho, there were only small areas of mangroves fringing the eastern and western shores of Sham Wat, and no species of special concern were recorded.
10.4.3.68 Tam and Wong (1997) surveyed the main mangrove stand in Tai Ho Wan. They found this 1.86 ha stand to be the third largest mangrove on Lantau, after Tung Chung and San Tau. The Tai Ho Bay mangroves harboured all of Hong Kong's mangrove species except Lumnitzera racemosa and the extremely restricted Heritiera littoralis (ibid.). Tai Ho Wan also had the densest mangrove stand encountered in the study.
10.4.3.69 During the EBS, the number of floral species recorded in Tai Ho was fairly high. There were six true mangrove species including Lumnitzera racemosa, Kandelia candel, Bruguiera gymnorrhiza, Avicennia marina, Aegiceras corniculatum and Acanthus ilicifolius. In addition to these true mangrove species, a number of mangal-associated flora, such as Limonium sinense, Clerodendrum inerme and Acrostichum aureum were also recorded. Other common species recorded within the coastal or mangrove communities included Zoysia sinica, Suaeda maritime and Vitex rotundifolia.
10.4.3.70 During a field visit in 2005, it was verified that the mudflat in Tai Ho Wan consisted of isolated patches of mangrove stands at the estuary of Tai Ho Stream and some inlet. 13 mangrove and mangrove associate species were recorded.
Seagrass Beds
10.4.3.71 North Lantau harbours a few locations of seagrasses including Tung Chung Bay, San Tau, Tai Ho Wan and Yam O. Tung Chung Bay is the largest lowland and river mouth habitat on North Lantau, and has an extensive mudflat. San Tau, at the northwest of Tung Chung Bay mudflat, harbours the largest seagrass area on Lantau. Two species of seagrasses, Zostera japonica and Halophila ovalis (previously described as H. ovata), were recorded in San Tau Beach, and an area of 2.7 ha was designated a SSSI in 1994.
10.4.3.72 Both Zostera japonica and Halophila ovalis (previously described as H. ovata) are considered rare locally (Xing et al, 2000). Zostera japonica and Halophila ovata are usually found co-habiting the seaward margins of mangrove stands (AFCD 2003). San Tau is the only site in western waters among the five known sites in Hong Kong where Zostera japonica can be found (i.e. Lai Chi Wo, So Lo Pun, Siu Tan, Sheung Sze Wan and San Tau, see Kwok et al. 2005). Zostera japonica was previously thought to be limited to the temperate regions and is thus of special interest to plant biogeography.
10.4.3.73 Halophila ovalis is also considered to be of special scientific interest because it is one of the few marine flowering plants in Hong Kong (AFCD 2003). Apart from San Tau, Halophila ovalis (described as Halophila ovata) has been previously recorded in Tai Tam Bay, Ho Chung, Hoi Ha Wan, Wu Shek Kok and Lai Chi Wo (AFCD 2003). More localities for this species have been found in a territory-wide search of seagrass sites in Hong Kong, including Ham Tin, Kai Kuk Shue Ha, Nam Chung, Nim Shue Wan, Sheung Sze Wan, Siu Tan, To Kwa Peng, Tsam Chuk Wan and Yam O (Kwok et al. 2004).
10.4.3.74 These two seagrass species at San Tau were surveyed during some previous studies and was found that much of the seagrass beds lied outside the SSSI (Mott 1998).
10.4.3.75 During the EBS study, the field surveys for seagrass beds were undertaken between 2003-2004. Field survey results confirmed that the seagrass bed at San Tau Beach SSSI still supported the two seagrass species, Halophila ovalis (described as H. ovata in the EBS study) and Zostera japonica. (Appendix 10A).
10.4.3.76 It should be noted that the seagrass bed at San Tau has been subject to impacts associated with the reclamation works for the airport at Chek Lap Kok. The seagrass has, however, recovered since the works were completed.
10.4.3.77 During the field survey for TMCLKL in July 2008, however, no seagrass beds were found on the mudflat in Tung Chung Bay (Maunsell 2009). During the EVS study, a third species of seagrass, Halophila minor, was recorded in San Tau. Halophila minor was also previously recorded at Sunny Bay (previously called Yam O) in North Lantau (Yip & Lai 2006).
10.4.3.78 Patches of the seagrass Halophila beccarii were also recorded in Tai Ho Wan (Wu and Lee 1998, Fong 1998) and at the stream mouth within Tai Ho Stream SSSI (Mott 1998; Mouchel 2000). H. beccarii is widespread along the coast of various Southeast Asian countries (Hodgkiss and Morton 1978). H. beccarii was first recorded in Hong Kong at Tsim Bei Tsui in Deep Bay (ibid.). Besides Tsim Bei Tsui and Tai Ho, other sites where this species of seagrass was recorded included Starling Inlet (Wong 1998), Black Point (Xing et al. 2000), Sheung Pak Nai, Sha Kong Tsuen and Nam Chung Yeung Uk. (Kwok et al. 2005, with the largest H. beccarii bed in Ha Pak Nai (Fong 1999).). This seagrass species is considered locally rare (Xing et al. 2000). The seagrass beds are also an important nursery and feeding ground of horseshoe crabs. During the April 2004 survey, the seagrass Halophila beccarii habitat was found during low tide at Tai Ho Wan and supported more than 20 colonies each approximately 30cm X 30 cm in area. During the field survey for TMCLKL, however, no seagrass beds were found on the mudflat in Tai Ho Wan (Maunsell 2009). The Tai Ho seagrass beds are of importance due to the presence of a locally restricted seagrass species and also it is a horseshoe crab nursery site while horseshoe crabs are threatened by habitat loss in Hong Kong.
Horseshoe Crab
10.4.3.79 Horseshoe crabs are considered of conservation importance in Hong Kong. Three species have been reported in HKSAR waters: Tachypleus tridentatus, T. gigas and Carcinoscorpius rotundicauda (Chiu & Morton 1999). These represent all species known from the South China Sea, and three of four species known worldwide. All three species appear to be undergoing rapid population declines and are thought to be under severe pressure in the South China Sea, including Hong Kong waters, due to habitat loss, pollution and over exploitation (Huang 1997; Chiu and Morton 1999).
10.4.3.80 In an extensive study of the distribution of horseshoe crabs in Hong Kong conducted between March 1995 and June 1998, Tachypleus gigas was not recorded and its local status is uncertain (Chiu and Morton 1999.) It is likely that only two species of horseshoe crab (T. tridentatus and C. rotundicauda) are currently widely distributed in Hong Kong as no recent records of T. gigas are available (Chiu and Morton 1999; Mouchel 2002c).
10.4.3.81 Horseshoe crabs are currently more often found in western waters of Hong Kong, though they were once thrived on many beaches in Hong Kong including Tolo Harbour (Huang 1997; Huang et al. 1999). Conformed nursery sites for horseshoe crabs in recent years included Pak Nai, San Tau and Shui Hau (Huang et al. 1999), together with Tai Ho Wan (Fong 1999). Some other beaches on Lantau, including Tai O, Yi O, Sham Wat Wan, Sha Lo Wan and Tung Chung, are considered of high possibility due to the records that adult horseshoe crabs were frequently fished offshore (Huang et al. 1999). At a territory-wide study, three locations, i.e. Pak Nai in Deep Bay, San Tau near Tung Chung, and Shui Hau at south Lantau, are identified as important horseshoe crab nursery sites, all of which are located at western waters (Chiu & Morton 1999).
10.4.3.82 Horseshoe crabs are known to be sparsely distributed along the coastline of Lantau Island and most survey effort of the EBS was expended at bays within the study area where suitable microhabitats were present (typically well-aerated sediment substrates near to seagrass beds; substratum adjacent to streams). These areas included Hau Hok Wan, Pak Mong, San Shek Wan, San Tau, Sha Lo Wan, Sham Wat, Tai Ho Wan and Tung Chung Bay. Several embayments with confirmed records of horseshoe crab juveniles including Tai Ho Wan, San Tau, Hau Hok Wan, Sha Lo Wan, and Sham Wat were considered as ecological sensitive receivers in the present EcoIA (see Figures 10.1 & 10.2).
10.4.3.83 During the field surveys of the EBS, horseshoe crab juveniles were recorded in Tai Ho Wan and Pak Mong (fourteen live and three molts of Carcinoscorpius rotundicauda), San Tau (10 Tachypleus tridentatus and 1 Carcinoscorpius rotundicauda), Tung Chung Bay (26 Tachypleus tridentatus), Hau Hok Wan (Two T. tridentatus and one C. rotundicauda), and Sham Wat (one live and three molts of Tachypleus tridentatus). During the EVS study, Horseshoe Crab Tachypleus tridentatus was recorded at two of the soft shore sites, Tung Chung Bay and San Tau. Two records from Tung Chung B ay included a juvenile (max. width of prosoma = 40mm) and one dead subadult (max. width of prosoma = 150mm). The single crab at San Tau was one tiny juvenile (max. width of prosoma = 5mm). Besides seagrass beds, it is also one of the three recognized horseshoe crab nursery sites Hong Kong (Huang et al. 1999 ;Chiu and Morton 1999). During the TMCLKL study, two Tachypleus tridentatus and three Carcinoscorpius rotundicauda were recorded at San Tau in July 2008. In addition, two Carcinoscorpius rotundicauda were recorded at Tung Chung Bay.
Subtidal Ecological Baseline for the North Western Water Control Zone
Marine waters
10.4.3.84 The assessment area for marine ecology in the present EIA covers a large sketch of sea areas including 7 water control zones. As the areas outside North Lantau waters are far away and sheltered from the project site by Lantau Island, they would be unlikely to be impacted by the project. The present EcoIA would thus focus on North Lantau waters.
10.4.3.85 The HKLR alignment goes through the waters in Hong Kong western boundaries while the proposed reclamation site for HKLR is adjacent to the southeast shore of Airport Island and that for HKBCF is located near the Northeast corner of Airport Island, and are all surrounded by North Lantau waters. Water depths off the North Lantau reclamation range up to 20m, with the deepest waters in the swift tidal channel of Urmston Road. Water depths in the area just off the NLH are shallower, generally less than 5 m.
10.4.3.86 North Lantau waters also receive effluent from the Urmston Road, Pillar Point and Siu Ho Wan marine discharge outfalls as well as numerous small-scale outfalls. Quantities of effluent from all three major outfalls are predicted to rise continuously (Smith-Evans and Dawes 1996, Maunsell 1997).
10.4.3.87 The North Lantau waters between Tuen Mun and Airport Island are a spawning/nursery grounds for fish and shrimp (ERM 1998). The North and West Lantau waters are important habitats for Chinese White Dolphin in Hong Kong (detailed in below sections on Chinese White Dolphin).
Chinese White Dolphin
10.4.3.88 There are sixteen recorded cetacean species from Hong Kong waters (Jefferson and Hung 2007). And recently in March 2009, a humpback whale was reported in Hong Kong. This made the number of recorded cetacean to seventeen species. Only two of these recorded species, the Chinese White Dolphin (CWD in short form, also commonly known as Indo-Pacific humpback dolphin, Sousa chinensis) and Finless porpoise (Neophocaena phocaenoides) are resident. Chinese White Dolphin is present in the coastal and inshore waters throughout the Indo-pacific, from Australia and China in the east to South Africa in the west (Jefferson and Karczmarski 2001). Off the coast of south China, at least seven separate populations were identified from Guangxi up to the mouth of the Yangtze River, and all coincide with the presence of river mouths (Jefferson and Hung 2004).
10.4.3.89 One population of Chinese White Dolphin lives in the estuary of the Pearl River, where they inhabit waters of the Hong Kong SAR, Macau SAR and Guangdong Province of the People’s Republic of China (Zhou et al. 1995; Jefferson and Hung 2004). In Hong Kong, Chinese White Dolphin is also concentrated in the more estuarine-influenced waters, i.e. all the waters of western Hong Kong. They are present commonly year-round in the waters north and west of Lantau, and also occur seasonally or in small numbers to the south and east of Lantau Island, as well as in southern Deep Bay and to the west of Lamma Island (Jefferson 2000, Jefferson & Hung 2004). They are not present in the waters to the east of Lamma Island, except for occasional wanderings.
10.4.3.90 From September 1995 through November 1998, the Hong Kong Airport Authority and the Agriculture, Fisheries and Conservation Department (the then AFD) funded several studies on the biology of the population of Chinese White Dolphin in Hong Kong waters. The results of these early studies indicated that the dolphin population shared with mainland China (Pearl River Estuary) and probably Macao, was much larger than originally estimated, and was probably viable in the long term if appropriate conservation measures were taken (Jefferson 1998, 2000).
10.4.3.91 Chinese White Dolphin is also present in the rest of the Pearl River Estuary outside (to the west) of Hong Kong. Before systematic surveys for the Tonggu Waterway study began in late 1997, there were only sporadic and opportunistic records of CWD from Mainland waters of the Pearl River Estuary (Yang and Chen 1996). From the Tonggu systematic surveys as well as additional systematic surveys conducted in 1999-2000, it has been confirmed that the distribution of Chinese White Dolphin extends throughout the entire Pearl River Estuary from Hu Men in the north to Guishan Dao and Dong’ao Dao in the south (Jefferson & Hung 2004).
10.4.3.92 Through investigation on CWD individual movements and ranging patterns (Hung 2000; Hung & Jefferson 2004), it is confirmed that many identified CWD had ranges that spanned across the Hong Kong/Mainland boundary. A single population of CWD is therefore involved in Hong Kong and Pearl River Estuary, and the population size has been estimated using line-transect methods to be about 1300 – 1500 individuals, with roughly 200 individuals using Hong Kong waters on a regular basis (AFCD 2007).
10.4.3.93 There appears to be seasonal shifts of CWD occurrence with the extent of river influence, moving farther south and east from the Pearl River in the wet season, and farther into the estuary proper in the dry season (Jefferson 2000).
10.4.3.94 Calving seasonality was determined by computing an estimated birth date for each neonate and fetus in the sample, based on the average length at birth, along with fetal and early neonatal growth rates from the literature (Jefferson 2005). Breeding appears to occur throughout the entire year, but there is a peak in the occurrence of births between the months of March and August (Jefferson 2005).
10.4.3.95 Western and Northern Lantau waters are the most important range of the Chinese White Dolphin in SAR waters. This has been concluded from systematic boat surveys for Sousa chinensis in Hong Kong waters since 1996 (AFCD 2008). Several hotspots were consistently used by CWD since 2002, including the waters around Lung Kwu Chau, near Black Point, around the Brothers Islands, and the entire stretch of West Lantau waters from Tai O Peninsula to Fan Lau. These hotspots can be considered as the prime dolphin habitats in recent years in Hong Kong. The coast of West Lantau area is of particularly high dolphin density (with densities even higher than in the North Lantau area and around the Sha Chau and Lung Kwu Chau Marine Park), and there are also frequent sightings of young calves in this area.
10.4.3.96 West Lantau waters are currently the most important area in Hong Kong for dolphin conservation as the highest encounter rate of CWD as well as juveniles and calves were recorded in that area. A quantitative grid analysis was developed and has been applied to AFCD long-term monitoring programme to examine fine-scale habitat use by CWD (Hung 2008). According to the results from the long-term AFCD marine mammal monitoring surveys (AFCD 2009), dolphin usage was the highest west of Lantau Island, where most grids (each of 1 km2) had moderate to high dolphin densities. Densities of CWD engaged in feeding and socializing activities, as well as densities of mother-calf pairs, were particularly high in West Lantau and east of Lung Kwu Chau, indicating the importance of these sites. Chinese White Dolphin frequently uses the whole stretch of the West Lantau waters between Fan Lau to Sham Wat, and some of the sightings of juvenile CWD were even beyond Sham Wat. This finding has been further supported by an additional AFCD land-based dolphin survey in 2004-2005 on the shore between Tai O to Sham Wat, specifically for facilitating the assessment of HZMB on CWD in the West Lantau waters (AFCD 2005).
10.4.3.97
There are also frequent sightings of
young calves and juveniles in the coast of
10.4.3.98
Besides West Lantau
waters, the waters around Lung Kwu Chau are also a dolphin hotspot in Hong
Kong, and having high densities of unspotted calves. Also in North Lantau
waters, Sha Chau and Lung Kwu Chau Marine Park, a marine area of 12 km2,
was designated in November 1996 with the primary objective of protecting S.
chinensis and its habitat. Two set of artificial reefs were also
deployed by government at the marine park and the northeast corner of
10.4.3.99 Vessel dolphin surveys were conducted for the EIA study on Liquefied Natural Gas receiving terminal in Northwest Lantau waters and Deep Bay between July 2005 and May 2006. 109 sightings of Chinese White Dolphin were recorded in West Lantau waters, 79 in Southwest Lantau waters, 62 in Northwest Lantau waters, while only 25 sightings were made in Deep Bay. In Northwest Lantau waters, the encounter rate in autumn and winter are higher than those in spring and summer.
10.4.3.100 A systematic Chinese White Dolphin line-transect survey in the Pearl River Estuary and Hong Kong waters (covering all of Hong Kong’s waters and Pearl River Estuary from Hu Men in the north to Aizhou Dao (隘洲島) in the southeast and Sanzao Dao (三灶島) in the southwest) was conducted between February 2006 to January 2007 for the study on “Proposed Port Development at Northwest Lantau”. It covered the entire known range of the Chinese White Dolphin population in the Pearl River Estuary, and the waters at the exit of Modaomen(磨刀門), in order to calculate abundance and density in a 12-month period. In Hong Kong waters of the Pearl River Estuary, individuals of Chinese White Dolphin were frequently sighted along the narrow strip of coastal waters west of Lantau waters. Most sightings were made near Tai O Peninsula (大澳半島), Kai Kung Shan (雞公山), Peaked Hill (雞翼角) and Fan Lau (分流). The frequency of dolphin occurrence was slightly higher along the inshore transect lines than the offshore ones. The dense distribution of dolphin sightings throughout West Lantau was in accordance with results from AFCD’s long-term monitoring studies.
10.4.3.101 18 systematic line-transect dolphin vessel surveys were conducted from July 2008 to March 2009 for TMCLKL study. The survey area covered the central portion of North Lantau waters between Pillar Point and Brothers Islands. 30 groups of CWD numbering 100 individuals were sighted, with most sightings (22 sightings) made in the western section of Northeast Lantau survey area (the transect covering the Brothers Islands), while another eight sightings were made in the eastern section of Northwest Lantau survey area.
10.4.3.102 The waters to the east of Airport Island and the waters to the west of Airport Island were the potential areas for locating HKBCF during the early stage of the HKBCF EIA study. To facilitate the ranking of the options, a desk-top study on the dolphin use of both areas was conducted. Both the potential HKBCF locations at the eastern and western Airport were covered by dolphin vessel survey transect adopted for AFCD regular annual dolphin monitoring programme. The dolphin monitoring data thus provided relevant information for assessing the dolphin use in these two locations. Dolphin sightings in North and West Lantau waters during 2002-2008 were reviewed. Positions of on-effort sightings of Chinese White Dolphin from 2002-08 were retrieved from the long-term sighting database and then plotted onto 1 km2 grids in the waters around Lantau Island. It was found that during the 2,857 dolphin groups (or 11,189 individuals) sighted during vessel and helicopter surveys in North and West Lantau waters between year 2002 and 2008, only a few dolphin sightings overlapped with the potential location to the east of Airport, while more sightings overlapped with the potential location to the west of Airport. Moreover, for the section of transect to the south of the options, only a handful of sightings were made to the south of the eastern Airport option (the waters immediately to the east of Airport), while CWD were frequently sighted immediately south of the western Airport option. Furthermore, for the coastal waters, dolphin sightings were densely distributed along the coastal waters from Shum Wat to Tai O, while there are very limited sightings on Tung Chung coastlines except the waters around the Brothers Islands and Sham Shui Kok. For seasonal pattern, dolphin sightings were only recorded in the eastern Airport option during autumn months, while the sightings were made during all four seasons in the western Airport option though fewer sightings were made in spring months. The overall abundance of Chinese White Dolphin at several survey areas was estimated by Jefferson (2007), using line-transect analysis with vessel survey data collected during 2004-06. It was found that the area with highest dolphin density was the West Lantau waters, with exceptionally high densities in all four seasons of 159-219 individuals/100 km2. Moreover, dolphin density at Northwest Lantau was quite high with 52-107 individuals/100 km2, and the one at Northeast Lantau was relatively low with 6-34 individuals/100 km2 (Jefferson 2007). Since dolphin densities were much higher in West and Northwest Lantau than in Northeast Lantau among all four seasons, it appeared that dolphin usage at the western Airport option (which lies in between the Northwest Lantau and West Lantau survey areas) should be much higher than the one at the eastern Airport option (which lies in between the Northwest Lantau and Northeast Lantau survey areas).
10.4.3.103 Ranging patterns of 54 individuals of CWD re-sighted 10-123 times since 1995 and with their ranges spanning the Northeast, Northwest and West Lantau survey areas were examined. Of these 54 individuals, 49 of them (90.7%) had their ranges overlapped with the western Airport option, and 37 individuals (68.5%) had their ranges overlapped with the eastern Airport option. The eastern Airport option is thus preferred and has become the present proposed HKBCF.
10.4.3.104 Although the HKBCF lies within the range of dolphin activities and sightings, few sightings were made in the HKBCF reclamation site. Based upon the data from the AFCD dolphin surveys between 2002 and 2008, the mean SPSE values per grid of all 356 grids around Lantau Island was 4.1 ± 6.12, while the mean DPSE values per grid was 16.0 ± 25.77. A total of four grids in Northeast Lantau survey area overlapped with the HKBCF reclamation, and the mean SPSE and DPSE values among these four grids were 2.8 and 10.9 respectively, which were both below the overall means of all grids around Lantau.
10.4.3.105 For the HKLR, its reclamation along the southeast shore of Airport Island and the part of viaduct inside the Airport Channel are within areas with no dolphin sighting records. The waters to the east of Airport Island and offshore Tung Chung are rarely used by the Chinese White Dolphin. Even though a transect line (i.e. the westernmost transect line in Northeast Lantau) run through the area of HKBCF site extending toward Tung Chung, it is found from the desk-top study that only two dolphin sightings were made in this area (between Tung Chung and Airport eastern shore) from 2002-08.
10.4.3.106 The sections of viaduct between Sham Wat to the HKSAR boundary are (i.e. the HKLR marine section open sea part in the below impact assessment) in waters of various levels of dolphin densities, ranging from 0.1-20.0 DPSE to 61.0 – 80.0 DPSE. Only a section of viaduct offshore to Tai O Peninsula gets close to a grid cell with higher DPSE value (61.0-80.0 DPSE) at its northeast corner and this grid cell is the only one with relatively high dolphin density among all grid cells along the HKLR alignment.
10.4.3.107 In the vicinity of the proposed HKBCF reclamation site, the records of calves and juveniles were low in comparison with Lung Kwu Chau and West Lantau. During 2002-08, only two sightings of unspotted juveniles were made within the HKBCF reclamation footprint, while none for unspotted calves (Figures 10.9 & 10.10). During the 2008-2009 dolphin monitoring programme, no sighting of calves or unspotted juvenile was made inside or near the HKBCF reclamation footprint (Figure 10.11). The nearest sightings of calves and unspotted juveniles were made in the waters around the Brothers Islands,
10.4.3.108 For the HKLR alignment, as mentioned in above sections that its reclamation and viaduct inside the Airport Channel are not within dolphin habitats (areas with no dolphin sighting including adult and juvenile). During 2002-08, though only two sightings of unspotted calves were made on the HKLR alignment open sea part, there were over 11 sightings of unspotted juveniles along this section of alignment (Figures 10.9 & 10.10). There are three unspotted calves and unspotted juvenile sightings lie on or are very close to the HKLR alignment between Sham Wat to Tai O Peninsula during 2008-09 (Figure 10.11).
10.4.3.109 There was no frequent feeding activity of Chinese White Dolphin in the HKBCF reclamation site. During 2008-2009, no record of dolphin feeding behaviours was made in the site and its vicinity. While for HKLR, one feeding activity record and four socializing activity records were made on or close to its alignment offshore to Sham Wat.
10.4.3.110 It is noted that the waters around
Brothers Islands (to the east of the HKBCF reclamation site) are considered as
one of the dolphin hotspots in recent years. Although the HKBCF
reclamation is located outside the waters around
10.4.3.111The ecological values of marine waters in western
Finless Porpoise
10.4.3.112 Within Hong Kong Finless Porpoises occur in the waters to the south and east of Lantau Island, but have never been sighted north or west of Lantau. In addition, they occur in Hong Kong’s eastern waters, south of Lamma Island, Hong Kong Island, and in the Po Toi, Ninepins, Sai Kung, and Mirs Bay areas (Parsons et al. 1995; Jefferson & Braulik 1999; Jefferson et al. 2002a).
10.4.3.113 The total size of the local Finless Porpoise population is not known, but based on line transect analyses, there are estimated to be between 55 (the low season in autumn) and 152 (the peak season in spring) porpoises in Hong Kong’s waters in different seasons, and up to 217 finless porpoises occur in the area of Hong Kong plus Mainland waters immediately to the southwest that have been surveyed (Jefferson et al. 2002a). The minimum estimate of the population size is thus about 220 porpoises, although the true size of the population is likely to be much larger. Breeding is strongly seasonal, and although some may be born at other times of year, most calves are born from October to January (Jefferson et al. 2002b).
10.4.3.114 Nothing is known of ranging patterns for individual finless porpoises, as individual specimens cannot be identified at sea, and no tagging or marking studies have been done. Feeding habits are known only from examination of stomachs of dead, stranded specimens (Barros et al. 2002). Porpoise prey includes many different species of fish, several types of cephalopods and at least one kind of shrimp. Porpoises prey on reef-associated organisms, but these are not primary constituents of the Finless Porpoise diet. Although field observation is currently lacking, there is some indication from stomach contents that porpoises may also feed in association with fishing vessels.
10.4.3.115 Finless porpoises do not occur in North Lantau waters, and within Hong Kong waters, finless porpoise are widely distributed in the southern and eastern waters (Jefferson et al. 2002a). There was also no porpoise recorded within the proposed HKBCF reclamation area and its vicinity or the HKLR alignment during the AFCD regular marine mammal monitoring as well as the land-based cetacean survey mentioned above.
Soft substrate seabed
10.4.3.116 Seabed sediments in North Lantau waters display a range of types: those in deeper and swifter-moving waters such as Urmston Road are dominated by coarse material, while those in areas with slower-moving currents are dominated by mud, silt and clay (Greiner Maunsell 1991). This variety of benthic substrates was found to foster a diversity of burrowing infauna in grab samples conducted in 1990 (Greiner Maunsell 1991).
Benthos
10.4.3.117 There is no known macrofauna species of conservation interest in Hong Kong, other than the cephalochordate Branchiostoma belcheri. The species is regarded as living fossil link in the evolution of marine invertebrates to vertebrates and is, therefore, considered a potentially important species. The species, however, is typically recorded in the eastern waters of Hong Kong (CCPC 2002) and recently to the south of Cheung Chau (Mouchel, 2003). No species of conservation importance were recorded in the Western waters stratum.
10.4.3.118 Parts of the seabed off North Lantau (beyond the project footprint of the present project) have been used as marine borrow and spoil dumping sites. Contaminated spoil is dumped at the East Sha Chau dumping grounds, where benthic grab samples indicate a fauna low in species diversity, and highly variable due to natural and human disturbance (ERM 1996). More recent monitoring results in the mud pits also revealed similar conditions in the benthic and demersal communities (Mouchel 2002a).
10.4.3.119 Surveys of benthic fauna had been conducted off North Lantau for various studies. In a territory-wide benthic survey commissioned by AFCD (CCPC 2002), up-to-date information on the subtidal benthic communities, with respect to spatial distribution, abundance, and species composition, was collected at 120 sampling stations over the territorial waters of Hong Kong which was divided into 5 strata (regions). One of the strata, Western waters with 29 sampling stations, covers Urmston Road, Deep Bay and North Lantau, and is more relevant with the works areas of the Project. Station 18 is more relevant with the Project as this station is located in the vicinity of the Project footprint (Figure 10.7).
10.4.3.120 Station 18 is located in to the north of Airport Northeast corner. The water depth of Station 18 is 8m, and in summer the mean Total Organic Matter TOM was 3.64%, lower than the average in Hong Kong (6.04%). The species richness index (d) was 5.62, the species, individual and biomass density were 38 species, 1,444 individuals, and 1,347.68 g/m2 respectively. The diversity index, H’, was 1.52 and evenness, J, was 0.42. Common species in the group of stations covering Station 18 included annelids of Mediomastus sp., Aglaophamus distranchis and Apionsoma trichocephalus.
10.4.3.121 In winter, the mean TOM in Station 18 was 4.39%, lower than the average in Hong Kong (5.45%). A species richness (d) of 8.06 was recorded and the density of species, abundance and biomass were 52, 1,120 individual/m2 and 263.38 g/m2 respectively. H’ was 2.14 and J was 0.54. Common species in the group of stations covering Station 18 included annelids of Prionospio ehlersi, Mediomastus sp., Apionsoma trichocephalus, Aglaophamus distranchis and Neoxenophthalmus obscurus.
10.4.3.122 Species richness, diversity and evenness indices are inter-related. A diversity index integrates two components: the total number of species and the distribution of individuals among species, into a single number (H’). H’ is usually high (e.g. >3 or 4) in environmentally undisturbed benthic communities, and low (e.g. <1) in highly disturbed communities (Gray 1989). Values for richness, diversity, and evenness would be high, with d>10, H’>3 and J (evenness) >0.8 for a diverse community structure. In benthic habitats where organic matter is concentrated or dissolved oxygen is low, such values are low, with d<5, H’<2, and J<0.5. Results in above paragraphs show that Station 18 is of moderate species richness, low diversity, and low evenness in both summer and winter seasons. No species of conservation importance was recorded. The only known benthic macrofauna species of conservation interest in Hong Kong, the cephalochordate Branchiostoma belcheri was not found in this station. This area is therefore not of special conservation importance in terms of benthic communities.
10.4.3.123 The diversity and abundance of benthic infauna in North Lantau display a high level spatial variation. Among the four CCPC sampling stations around Airport Island (i.e. Station 18 at the northeast Airport Island described above, Station 19 at the Northwest of Airport Island, Station 20 to the east of Airport Island at Brothers Islands, and Station 21 to the west of Airport Island, the density of benthos in summer varied from 218 no./m2 (Station 20) to 1,444 no./m2 (Station 18), and the biomass varied from 11.52 g/m2 (Station 21) to 1,347.68 g/m2 (Station 18). During winter, similar spatial variations are observed, with the density of benthos varied from 36 no./m2 (Station 20) to 1,120 no./m2 (Station 18), and the biomass varied from 15.12 g/m2 (Station 19) to 263.38 g/m2 (Station 18).
Table 10-5 The number of species, density and biomass of benthic infauna from four CCPC benthic stations near Airport
Station |
|
Summer |
|
|
Winter |
|
|
No. of species (0.5m2) |
No. of Individual (m2) |
Wet weight (g/m2) |
No. of species (0.5m2) |
No. of Individual (m2) |
Wet weight (g/m2) |
18 |
38 |
1444 |
1347.68 |
52 |
1120 |
263.38 |
19 |
41 |
650 |
77.80 |
54 |
664 |
15.12 |
20 |
27 |
218 |
38.58 |
13 |
36 |
18.38 |
21 |
38 |
460 |
11.52 |
37 |
296 |
38.62 |
10.4.3.124 Grab sampling were conducted at 15 sampling stations in North Lantau inshore waters at both wet and dry seasons during the EBS study. 15 sampling stations were sampled from three zones, i.e. HKS (to the west of Airport Island), NLHC (within Airport Channel) and THW (to the east of Airport Island). In the wet season, species abundance and diversity was higher outside (32.6 individuals and 4.2 taxa grab-1) than inside Airport Channel (9.2 individuals and 2.4 taxa grab-1). In the dry season, conversely, species abundance and diversity was higher inside (46.2 individuals and 9.8 taxa grab-1) than outside (23 individuals and 5.6 taxa grab-1) Airport Channel (Appendix 10A). The marine benthic macrofauna was comprised of a high diversity of polychaete species, in which Sigambra hanaokai was the dominant species in the wet season, while Eunice indica and Prionospio sp. dominated in the dry season. Species diversity of other taxa (mainly crustaceans, echinoderms and molluscs) and the overall biomass were, however, low, which is typical in the North-western waters of Hong Kong (ERM 2000; CPCC 2002; Mouchel 2002). All the species recorded occur frequently in Hong Kong and no rare species were observed (CPCC 2002). The biotic index of ~ 2 – 3 and the dominant species recorded implies the community is slightly disturbed.
10.4.3.125During wet season, the recorded benthic species number in THW Area was 23 taxa including annelid (with the dominant families of Spionidae, Pilargiidae, Poecilochaetidae, and Capitellidae) and crustacean (with the most abundant group of amphipod Corophiidae), the individual number was 163, the density of benthos was 32.6 individual/grab (or 326 individual/m2), and the biomass was 0.76 g/grab (or 7.6 g/m2)
10.4.3.126 In dry season (winter), the recorded benthic species number in THW Area was 28 taxa also including annelid (with the dominant families of Spionidae and Capitellidae) and crustacean (with the most abundant group of amphipod Corophiidae), the individual number was 115, the density of benthos was 23.0 individual/grab (or 230 individual/m2), and the biomass was 0.54 g/grab (or 5.4 g/m2)
10.4.3.127 Infauna diversity to the east of Airport Channel was relatively low (H’ at THW = 0.97) compared to other areas in Hong Kong. The impoverished assemblages present is likely due to the proximity of Pearl River Estuary (estuarine areas are often less diverse owing to their highly dynamic physical and chemical nature) and possibly due to the predominantly silt-clay composition of the seabed that tends not to support high diversity (Shin 1998; Mouchel 2002b; CCPC 2002).
10.4.3.128 The major conclusion from other previous work in the North-western waters as summarised in Mouchel (2002b) was that benthic macrofauna present are impoverished and relatively similar throughout the North-western waters and are representative of the general study area.
10.4.3.129 Marine grab samplings of EVS study were conducted for benthic communities in soft substrate seabed at 9 stations along the mid 2008 HKLR alignment during both wet season and dry seasons (September 2008 and December 2008). The mid-2008 HKLR alignment and the sampling locations are shown in Figure 10.3 and Figure A1.1.3 in Appendix 10B. Three grab sample replicates of 0.1m2 were collected at each of the sampling stations by van Veen-type Grab and collected samples were sieved using a 0.5mm mesh-size sieve and then preserved in 70% ethanol. Organisms inside the samples were sorted from the sediments by staining with Rose Bengal and then identified to the lowest practicable taxonomic level. Species composition, abundance and biomass were reported and statistical analyses (Diversity index, evenness index and Abundance/Biomass Comparison (ABC) plots), were provided for evaluation and ranking of ecological values.
10.4.3.130 A total of 985 macro-faunal specimens, comprising 90 species from 59 families in 9 phyla (Annelida, Arthropoda, Branchiopoda, Chordata, Cnidaria, Echinodermata, Mollusca, Nemertea and Platyhelminthes), were recorded in the wet season. In the dry season, a total of 383 macro-faunal specimens comprising 58 species from 44 families in 6 phyla (Annelida, Arthropoda, Coelenterata, Echinodermata, Mollusca and Nemertea) were recorded. Only 28 species were found in both seasons. Polychaetes (Annelida) were collected at all stations and represented the highest species richness and abundance in both seasons.
10.4.3.131 The bivalves Donax sp. and Theora lata and the brittle star Macrophiothrix longipeda were the commonest species recorded in the wet season, whilst the polychaetes Notomastus latericens and Euclymene sp. and the pea crab Xenophthalmus sp. were the most abundant species recorded in the dry season. Detailed data are presented in Appendix 10B.
10.4.3.132 Species abundance and richness were higher in the wet season than in the dry season (using two-way ANOVA, p < 0.001), except in Station 7 where the species abundance and richness remained constant. The overall patterns were, however, similar in both seasons: higher in open waters (Stations 1-3, 8 & 9) and declining gradually towards the Airport Channel. In the wet season, Stations 2 and 3 possessed the highest species abundance and Station 1 had the highest species richness. The lowest species richness and abundance occurred in Station 7. In the dry season, the species abundance and richness were highest in Stations 2 and 3 and were lowest in Stations 5 and 6.
10.4.3.133 The Pielou’s Index was similar between seasons and stations (wet season: 0.75 – 0.93, dry season: 0.79 – 0.99). The Shannon-Wiener Diversity Index was slightly higher in the wet season than in the dry season, but the variation between stations is slight (wet season 2.68 – 3.37, dry season: 1.84 – 2.57).
10.4.3.134 The overall biomass was higher in the dry season than in the wet season (using two-way ANOVA, p < 0.05). The values in both seasons were, however, variable between stations and no general patterns could be deduced. Total biomass in the wet season was 30.94 g and was mainly due to the relatively high mass of molluscs (22.1 g) and arthropods (5.5 g). Juveniles (~1 – 5 mm length) of bivalves and gastropods were recorded. Total biomass in the dry season was 131.53 g and was mainly due to the relatively high mass of molluscs (67.92 g), echinoderms (40.77 g) and arthropods (20.77 g). The biomass of other taxa in both seasons was low because of their small sizes and/or low abundance. Detailed biomass data are presented in Appendix 10B.
10.4.3.135 The W statistics for the 9 stations during the wet season were all positive and generally similar (0.225 – 0.411), although Station 7 possessed the lowest value of 0.11 and Station 9 had the highest value of 0.556. The W-statistics for the 9 stations during the dry season were also positive and the values were higher than those recorded in the wet season (0.264 – 0.739).
10.4.3.136 In both wet and dry seasons, none of the species are mentioned in the IUCN Red List (IUCN 2009). One species is listed in the China Species Red List (CSIS 2008): the Greasyback Shrimp Metapenaeus ensis is listed as Vulnerable due to over-exploitation in China. This species indeed is commercially important in many Asian countries (Leung et al. 2004). In Hong Kong, Metapenaeus ensis is a common fisheries species, and is also one of the major species cultured in the tidal shrimp ponds “Gei Wais” in Mai Po, and commonly known as “Gei Wai Shrimp” in the local market.
10.4.3.137 The marine benthic macrofauna in North Lantau was composed of a high diversity of polychaete species and a low diversity of other taxa, which is characteristic in the North-western waters of Hong Kong (ERM 2000; Shin, 2002; Mouchel, 2002). There was, however, a distinct spatial and temporal pattern, suggesting the benthic macrofauna are sensitive as a biological indicator to reflect changes in environmental conditions (Shin, 2002).
10.4.3.138 Spatially, species abundance and richness were higher outside than inside the Airport Channel. The large error bars indicate that species abundance and richness varied considerably within sites.
10.4.3.139 Temporally, species abundance, richness and diversity (Shannon-Wiener Diversity Index) were higher in the wet season than in the dry season. The small individual sizes observed and the low biomass recorded in the wet season may suggest that the majority of the benthic macrofauna recruit during this time period. The decrease in species abundance and richness in the dry season is possibly an indication of post-recruitment mortality of the benthic macrofauna. The similarity in the Pielou’s Evenness between seasons and stations indicates the species evenness was constant over time alike among the 9 stations.
10.4.3.140 Infauna diversity in the North Lantau waters is relatively low when compared to other areas in Hong Kong. The impoverished assemblages present is likely due to the proximity of the Pearl River Estuary, leading to low salinity and possibly due to the predominantly silt-clay composition of the seabed which does not lend itself to supporting high diversity (Shin 1998). All the species recorded occur frequently in Hong Kong and no rare species were observed (Shin 2002).
10.4.3.141 The benthic communities in the waters offshore to the southeast coast of Airport Island were also investigated in the MSS study. From the 8 sampling stations, a total of 917 organisms from 83 taxa were identified from the dry season survey. The most diverse group was polychaetes (46 species). In terms of number of individuals, 43% of collected organisms were polychaetes, followed by crustaceans (35%).
10.4.3.142 During the dry season benthic survey under the MSS study, 345 organisms were identified from the sediment samples collected. In wet season, 58%, 15%, 12%, 8% and 7% of organisms collected were polychaetes, molluscs, crustaceans, echinoderms and other phyla, respectively. The total biomass was 130.87 g, in which 52%, 27%, 15% and 6% of total biomass were accounted by echinoderms, molluscs, crustaceans and other phyla, respectively.
10.4.3.143 The benthic communities inside the footprints of HKBCF reclamation (the waters offshore to the northeast coast of Airport Island) were also investigated in the HKBCF survey programme. 559 organisms from 80 taxa (210 individuals weighted 264.28g and 349 individuals weighted 179.73g from dry season survey) were collected from 9 sampling stations within the HKBCF reclamation area. Detailed results are presented in Appendix 10D. No species of special conservation importance was found. The results are basically similar with those from the grab sampling surveys of EVS and MSS.
10.4.3.144 During the TMCLKL study, benthic samplings were conducted at 8 stations along the alignment in October 2008 and February 2009. 917 individuals from 50 families comprising 8 different phyla. The total recorded biomass was 58.0 g due to the high mass of molluscs, echinodermata, annelida and arthropoda. The infauna density was 382 individuals/m2, and the average biomass was 24.2g/m2. The dry seasons survey collected 1,579 individuals from 50 families comprising 7 different phyla. The total recorded biomass was 73.1g. The density was 658 individuals/m2 and the average biomass was 30.46 g/m2.
10.4.3.145 The soft substrate seabed of the vast Hong Kong western waters also provides a habitat for adult horseshoe crab. Though the available habitats are abundant, but the density of the adult horseshoe crabs is not high as this species is not a regular fishing catch. Adult horseshoe crabs are only occasionally collected during bottom trawling.
Hard substrate seabed
Corals
10.4.3.146 Recent information on coral ecology in North Lantau waters is provided by several studies as well as field survey programmes including the EBS, EVS, MSS, and the HKBCF.
10.4.3.147 Hard corals are protected in Hong Kong by the Protection of Endangered Species of Animals and Plants Ordinance (Cap 586) which includes the protection of all stony (hard) corals. Established coral communities of any size are regarded as important habitat types in Hong Kong as defined in Annex 8 of EIAO-TM.
10.4.3.148 Corals in Hong Kong exhibit strong gradients in distribution, species diversity and abundance. Hard corals are more vulnerable to water quality such as salinity and suspended solid and prefer clear oceanic water, and their geographical distribution in Hong Kong is affected by the salinity of the water. Hard coral coverage and diversity decrease from east to west, toward the influence of the Pearl River (Scott 1984). The estuarine environment of the western Hong Kong waters was thought unsuitable for the existence of scleractinians (reef-building corals)(Scott 1984). A later study demonstrated that water quality, particularly elevated freshwater and suspended sediment levels which are characteristic of estuarine environment, prevent substantial hard coral growth (Hodgson and Yau 1997). The vertical distribution of hermatypic corals is largely controlled by the requirements of their photosynthesising zooxanthellae which require strong light and hence shallower water, whereas many of the soft corals that do not possess symbiotic algae can survive at greater depths (Morton and Morton 1983; Morton 1994).
10.4.3.149 The North Lantau waters are within the estuarine western waters. In contrast to the oceanic eastern waters, the abundance and diversity of corals are low in western Hong Kong waters (in particular North-western waters which are closer to Pearl River Estuary). North Lantau waters are thus characterized by domination of gorgonian and soft corals. Soft corals, sea pens and gorgonian corals (sea fans) were reported to be present throughout the North-western waters (Mouchel 2002b, 2004).
10.4.3.150 AFCD commissioned intensive underwater surveys in 2001-2002 to survey corals at 240 sites covering about 70 km of coastline in territorial waters (AFCD 2004). Hard corals were found in western waters of Hong Kong, but in southern Lantau waters (Tong Fuk, Soko Islands) and eastern (Cheung Chau, Hei Ling Chau) Lantau waters, and only sparse colonies or low-coverage communities, composed of extremely tolerant and hardy species were found.
10.4.3.151 The coverage of corals in this region is very low (less than 5%, and usually < 1%, the lowest compared with other regions in Hong Kong). The “near-total or complete absence” of reef-building hard corals was considered attributable to the high turbidity and low salinity.
10.4.3.152 A dive survey targeting on corals
was conducted along the coastline from Sham Wat to Kei Tau Kok (to the east of
Tung Chung near Tai Ho) during the EBS. No hermatypic hard coral was
found at any of the 27 dive sites. Although ahermatypic corals were
recorded, but they were concentrated in sites to the west of the airport
island. The only widespread and common coral recorded in the survey was
one species of gorgonians Echinomuricea sp. which was found both to the
east and to the west of the airport island, but not inside the Airport
Channel. The species composition at the dive sites near the HKLR
reclamation for the at-grade road (the southeast coast of
10.4.3.153 A dive survey was conducted at the artificial seawalls near MTR depot at Siu Ho during the LLP EIA study. The survey site is basically facing to the Brothers in North Lantau waters. It is to the east of the outlet of Tai Ho Wan. Freshwater input from Tai Ho Stream is discharged into the nearby waters through this only outlet of Tai Ho Wan with the open sea.
10.4.3.154 It was found from the LLP dive survey that the topography of the subtidal habitats within the proposed LLP site is generally flat. The coastline is all sloping boulder artificial seawall.
10.4.3.155 The horizontal transect covered the seawall adjacent to the MTR depot. Along the transect the seabed composition was all boulders. The boulders on the seawalls were also heavily covered by fine sediment.
10.4.3.156 Though no alive or dead hard corals, colonies of gorgonian were found on the boulders of the artificial seawalls. They were all of small sizes (less than 10 cm in length) and scattered on the boulders, resulting in a low coverage (<1%). Partially mortality was also observed in many colonies, which indicated that these gorgonians were under stress. Other marine fauna species found during the survey included Fan Shell, Green Mussel, and Oyster, and they were common and of no special conservation importance in Hong Kong. The results from the present dive survey were basically consistent with those from the EBS dive survey, in particular the coral composition and coverage.
10.4.3.157 Dive surveys were conducted at seven dive survey sites (with DS1 near Sham Wat, DS2 at the western shore of Sha Lo Wan headland, 3 sites DS3, DS4, DS5 inside the Airport Channel, DS6 on the southeast shore of Airport Island, and DS7 on Tung Chung New Town) in 2008 during the EVS study. The results revealed that no coral was found within the Channel while the diversity and abundance of hard and soft corals outside the Airport channel were low. Most hard substrates were dominated by barnacles, mussels and rock oysters. At the western shore of Sha Lo Wan headland, i.e. DS2, the subtidal hard substrate extends less than 10m from the shore.
10.4.3.158 Only one genus of ahermatypic cup coral Balanophyllia (Dendrophylliidae) and one genus of octocoral, Echinomuricea sp. (Plexauridae) were recorded from two (DS1 and DS2) and four (DS1, DS2, DS6 and DS7) of the seven survey sites, respectively. Both the hard and soft corals were only present outside the Airport Channel. No coral was found within the Channel (i.e. DS3, DS4 and DS5).
10.4.3.159 No other taxa of high conservation interest were recorded in the seven survey sites. Full details of substrate type and fauna recorded are shown in Appendix 10B.
10.4.3.160 Compared with the EBS study, the spot dive in 2003 generated similar qualitative data as the EVS study. In the EBS study, the ahermatypic cup coral Balanophyllia sp. was only recorded outside the Airport Channel at site SD5 (DS1 in the EVS study), SD9 (DS2 in the EVS study) and SD22 (DS6 in the EVS study). In the EVS study, this cup coral was also recorded in DS1 and DS2 but not in DS6, which is probably due to the very low abundance and patchy distribution of the coral within same area. For the octocoral Echinomuricea sp., the results in the EVS study agree with the finding in the EBS study.
10.4.3.161 In Hong Kong context, the low salinity and murky water at the western Hong Kong limit the development of hard coral to few thriving species such as ahermatypic cup corals, Oulastrea crispata, Plesiastrea versipora and selected Favia species. At north and northwest Lantau, only Oulastrea crispata and ahermatypic cup corals have been reported. The low diversity and low abundance of corals in the present survey is typical for the western Hong Kong waters.
10.4.3.162 During the MSS study, 8 locations along the southeast shore of Airport Island were investigated by spot dive and two of them were further surveyed with REA technique. In the HKBCF survey programme, dive surveys were conducted at 7 locations along the northeast shore of Airport Island and 9 locations within the HKBCF reclamation site, with two shore locations where direct impacts are anticipated further studied by REA technique.
10.4.3.163 Only 2 out of the 8 dive locations in the MSS study had records of gorgonian coral Echinomuricea sp., and both sites (D1 and D8) are sloping boulder seawalls. The percentage cover of the gorgonian recorded was less than 1% and the gorgonians were of fair condition. The seabed within the HKBCF reclamation site was quite homogeneous, of all muddy seabeds, lacking the hard bottom substrate required for coral colonization and thus was not a habitat for corals. The sediment was very fine and no demersal fauna was sighted. As no hard substrate in these locations, no coral (both hard and soft) was found in the seabed within the reclamation site. The only hard bottom substrate in the area was the artificial seawalls which laid along the Airport Island shoreline, to the west of the HKBCF reclamation site. No hermatypic hard corals were found, but sparsely distributed small-sized gorgonian colonies (Echinomuricea sp.) were found at all seawall bounce dive points. The existing artificial sloping seawalls is comprised of both vertical (at Marine Cargo Terminal and Sky Pier) and sloping seawalls (Fire station and to the south of MCT). The vertical seawalls had no hard corals and very little soft corals, but with more common epifauna such as rock oysters. The seawall surveyed by REA was sloping boulder form. To further investigate the epifauna fauna on the seawall which was the only hard bottom substrate habitat in the area, two sections of 100m seawall was surveyed by REA in a horizontal transect pattern. The slope of the sloping artificial seawall maintained the gradient (about 45 degree gradient) in the subtidal zone and extended till it met the seabed. The boulders of the sloping seawalls were all irregular in shape and the largest ones were close to 1m in size. On the boulders of the sloping seawalls, there was no hermatypic hard coral, but a low coverage percentage of small-sized gorgonian colonies (Echinomuricea sp.) which is common in Hong Kong western waters and not of special conservation importance. Furthermore, partially mortality was observed on some branches of the gorgonian colonies, demonstrating the poor conditions of the gorgonians. Very low coverage of ahermatypic cup corals Balanophyllia sp. was found at the Northern REA transect at the Fire Station sloping seawall. Other epifauna on the boulders were mainly sessile bivalves including Green mussel Perna viridis and Oyster Ostrea sp., and predatory snail Thais sp. except the boulders at the seawalls, the seabed in the area was almost solely muddy substrate. Other fauna recorded on both the muddy seabed and the boulders of the seawall were also of low conservation importance including green mussels and oysters.
10.4.3.164 The hard substrate seabed along North Lantau coastlines were also surveyed during the dive survey of TMCLKL study. Low coverage of populations of soft coral Guaiagorgia sp. (< 10%) and ahermatypic coral Paracyathus rotundatus (< 5%) were found along the seawalls. Partial mortality (about 20%) of the population of Guaiagorgia sp. was recorded during the REA survey at this coastline. Other organisms recorded were common in Hong Kong, such as sponges, barnacles, oysters, coralline algae. No taxa of high conservation interest were recorded. It is expected that the salinity in the HKBCF site is diluted by the flow from Pearl River as in other locations in North Lantau waters, and it might explain the absence of hard corals in the HKBCF site. This might also explain the similarity in the results from the present study and those from EVS and MSS in which many dive sites near Tung Chung Bay which is the outlet of Tung Chung River and Wong Lung Hang Stream.
10.4.3.165 Basically, the marine communities showed no particular trend within the several study areas of different surveys in terms of diversity and abundance. The northeast and southeast coastlines of Airport Island are exposed to the open sea and no hermatypic coral coverage was found there. These results matched the results from the EBS during 2003-04. From the information presented in the previous sections, it is clear that the hard substrate subtidal habitats in the area can be considered as of low ecological value due to the absence of hermatypic coral, the low coverage and the small sizes of gorgonian and ahermatypic corals, and their poor conditions (with partial mortality on the branches of gorgonians).
Artificial Reefs
10.4.3.166 Artificial Reefs were deployed near the northeast corner of Airport Island within Marine Exclusion Zone 3 and at Sha Chau and Lung Kwu Chau Marine Park. Both ARs were deployed in 2000, with a footprint of 1,200 m2 (3,600 m3 in terms of volume) in the Marine Exclusion Zone, and a footprint of 3,660 m2 (3,600 m3 in terms of volume) in the Marine Park. The artificial reef units in the Marine Exclusion Zone comprised Ferro-cement vessels (build-up river barge) and natural materials (quarry rock), while the units in the Marine Park comprised Ferro-cement vessels (river barge) and concrete-coated materials (Steel Container). Primarily postulated as feeding stations for Chinese White Dolphin, these artificial reefs also help to enhance habitat quality and marine resources. As both sites are restricted, for either fishing or marine traffic, the undisturbed environment should facilitate a better development of the reef community and enhancement functions. The enhancement functions of artificial reefs deployed in Eastern waters were demonstrated by monitoring surveys, and it was recorded that juvenile fish were found to have settled after artificial reef vessels were deployed (Wilson 2003). While the ARs in the Marine Park is quite distant (approximately 7 km from HKBCF), the ARs in Marine Exclusion Zone is the nearest marine ecological sensitive receiver and is approximately 300m from the HKBCF reclamation and 1.5km from HKLR reclamation.
10.4.4 Evaluation of Ecological Importance of Habitats
10.4.4.1 The ecological importance of different parts of the assessment areas are evaluated based primarily on the criteria set forth in Table 2, Annex 8 of the EIAO-TM:
· naturalness;
· size;
· diversity;
· rarity;
· re-creatability;
· fragmentation;
· ecological linkage;
· potential value;
· nursery/breeding ground;
· age; and
· abundance/richness of wildlife.
Table 10-6a Ecological value of different habitats along HKLR and HKBCF
|
|
Terrestrial |
|
|
Criteria |
Woodland |
Shrubland |
Plantation |
Agricultural |
Naturalness |
Semi-natural |
Semi- natural |
Artificial |
Artificial |
Size |
About 22 ha |
About 67 ha |
23.5 ha |
About 0.05 ha |
Diversity |
Moderate |
Moderate |
Moderate |
Low |
Rarity |
Common habitat in Hong Kong |
Common habitat in Hong Kong |
Common habitat in Hong Kong |
Common habitat in Hong Kong |
Re-creatability |
Creatable through planting |
Creatable through planting |
Creatable through planting |
Readily creatable |
Fragmentation |
Unfragmented, except the woodland in Scenic Hill. |
Unfragmented, except the shrubland in Scenic Hill.. |
Unfragmented. |
Fragmented to a certain extent by paths and houses. |
Ecological linkage |
Generally linked with adjacent natural habitats except the woodland in Scenic Hill. |
Generally linked with adjacent natural habitats except the shrubland in Scenic Hill. |
No significant linkage |
Generally linked with adjacent natural habitats |
Potential value |
Low. Already a natural habitat. |
Low. |
Low. |
Low |
Nursery/breeding ground |
No special nursery/breeding ground function observed |
No special nursery/breeding ground function observed |
No special nursery/breeding ground function observed |
No special nursery/breeding ground function observed |
Age |
N/A |
N/A |
N/A |
N/A |
Abundance/Richness of wildlife |
Moderate |
Moderate |
Low |
Low |
Overall Ecological value |
High for Scenic Hill; Moderate –high for other woodlands Low-moderate for young woodland |
Moderate-high for tall shrubland and shrubland; moderate for grassland /shrubland; low for grassland/shrubland on Scenic Hill |
Low-moderate |
Low-moderate |
Table 10-6b Ecological value of different habitats along HKLR and HKBCF
|
|
Terrestrial |
|
Criteria |
Grassland/Seasonally wet grassland |
Developed area |
Streams |
Naturalness |
Natural. |
Artificial |
Basically natural. |
Size |
About 1 ha |
Over 300 ha |
NA |
Diversity |
Low |
Low |
Moderate |
Rarity |
Common habitat in Hong Kong |
Common and abundant in Hong Kong |
Common habitat in Hong Kong |
Re-creatability |
Re-creatable. |
Re-creatable. |
Difficult to re-create. |
Fragmentation |
Unfragmented. |
Unfragmented. |
Unfragmented. |
Ecological linkage |
Generally linked with adjacent natural habitats |
No significant linkage |
Linked with open sea |
Potential value |
Low. |
Low. |
Low. Already a natural and undisturbed habitat. |
Nursery/breeding ground |
No special nursery/breeding ground function observed |
No special nursery/breeding ground function observed |
No special nursery/breeding ground function observed, but some marine species might use estuarine areas as nursery grounds. |
Age |
N/A |
N/A |
N/A |
Abundance/Richness of wildlife |
Low |
Low |
Low to moderate |
Overall Ecological value |
Low |
Low |
Ranging from low to Moderate-high |
Table 10-6c Ecological value of different habitats along HKLR and HKBCF
|
|
Intertidal |
|
|
Criteria |
Hard shore - Rocky shore |
Sandy beach/ sandflat/ mudflat (including seagrass beds) |
Mangroves |
Hard shore - Artificial seawalls |
Naturalness |
Basically natural. |
Basically natural. |
Basically natural. |
Artificial |
Size |
About 6km |
NA |
0.94 ha within the 500m assessment area |
About 5.5km |
Diversity |
Low |
Low for sandy beaches; Low to moderate for San Shek Wan, and Moderate for other soft shores |
Low |
Low |
Rarity |
Common habitat in Hong Kong |
Common in Hong Kong for sandy beach; For the soft shores, limited in Hong Kong, with records of seagrasses and horseshoe crabs. |
Common habitat in Hong Kong waters. |
Common habitat in Hong Kong |
Re-creatability |
Not re-creatable. |
Re-creatable for sandy beach; Difficult to recreate for sandflat/mudflats. |
Creatable through planting |
Readily creatable |
Fragmentation |
Unfragmented. |
Unfragmented. |
Unfragmented. |
Unfragmented. |
Ecological linkage |
Generally linked with the open sea. |
Generally linked with the open sea and/or mangroves. |
Generally linked with sandflats/mudflats and the open sea. |
Generally linked with the open sea. |
Potential value |
Low. |
Low for sandy beaches; Moderate for other soft shores which are currently disturbed by the clam harvesting activities |
Low. Already a natural habitat. |
Low |
Nursery/breeding ground |
No special nursery/breeding ground function observed |
Sandflat/mudflats provide horseshoe crab nursery ground |
Breeding/nursery ground for marine species. |
No special nursery/breeding ground function observed |
Age |
N/A |
N/A |
N/A |
N/A |
Abundance/Richness of wildlife |
Generally low – moderate; low in the remnant rocky shore on Airport Island |
Low for sandy beach; Moderate for other soft shores |
Low to moderate |
Low |
Overall Ecological value |
Low – moderate for rocky shore on North Lantau ; Low for remnant rocky shore on Airport Island |
Low to moderate for San Shek Wan; Moderate to High for Sham Wat, Sha Lo Wan, Hau Hok Wan, San Tau, Tung Chung Beach and Tai Ho |
Moderate |
Low |
Table 10-6d Ecological value of different habitats along HKLR and HKBCF
|
|
Marine waters |
|
|
Criteria |
To the west of Airport Island |
Airport Channel |
Near eastern shore of Airport Island |
Northeast Airport Island |
Naturalness |
Natural |
Natural |
Natural |
Natural |
Size |
NA |
NA |
NA |
NA |
Diversity |
Low |
Low |
Low |
Low |
Rarity |
Common habitat in Hong Kong waters. Dolphin habitat. |
Common habitat in Hong Kong waters. No dolphin records. |
Common habitat in Hong Kong waters. No dolphin records |
Common habitat in Hong Kong waters. Dolphin habitat. |
Re-creatability |
Not re-creatable. |
Not re-creatable. |
Not re-creatable. |
Not re-creatable. |
Fragmentation |
Unfragmented. |
Unfragmented. |
Unfragmented. |
Unfragmented. |
Ecological linkage |
Potentially a corridor for dolphin movement between Sha Chau and Lung Kwu Chau Marine Park and West Lantau waters |
Generally linked with the open sea. Connect to soft shore habitats along the channel |
Not functionally linked to any high value habitats (e.g. mudflat) in close proximity. |
Potentially a corridor for dolphin movement between the Sha Chau and Lung Kwu Chau Marine Park and the Brothers Islands |
Potential value |
Low. Already a natural habitat. Development of coral colonies constrained by water quality |
Low. Already a natural habitat. Development of coral colonies constrained by water quality |
Low. Already a natural habitat. Development of coral colonies constrained by water quality |
Low. Already a natural habitat. Development of coral colonies constrained by water quality |
Nursery/breeding ground |
Potential breeding/nursery ground for marine species. |
Potential breeding/nursery ground for marine species. |
Potential breeding/nursery ground for marine species. |
Potential breeding/nursery ground for marine species. |
Age |
N/A |
N/A |
N/A |
N/A |
Abundance/Richness of wildlife |
Low to Moderate |
Low |
Low |
Low to Moderate |
Overall Ecological value |
Moderate-high |
Low |
Low |
Moderate |
Table 10-6e Ecological value of different habitats along HKLR and HKBCF
Criteria |
Hard substrate seabed |
Artificial reefs in Northeast Airport |
Soft substrate seabed |
Naturalness |
Partially natural, and partially artificial. |
Artificial |
Basically natural. |
Size |
NA |
1,200 m2 |
NA |
Diversity |
Low Colonised by low coverage of common gorgonians and ahermatypic corals |
Moderate |
Low |
Rarity |
Common habitat in Hong Kong waters.
|
Deployed in at least 8 locations within Hong Kong waters. |
Common habitat in Hong Kong waters.
|
Re-creatability |
Re-creatable. |
Re-creatable. |
Not re-creatable. |
Fragmentation |
Unfragmented. |
Unfragmented. |
Unfragmented. |
Ecological linkage |
Generally linked with the open sea. |
Generally linked with the open sea. |
Generally linked with the open sea. |
Potential value |
Low. Development of coral colonies constrained by estuarine environment |
Moderate. |
Low. Limited by the mobile nature of the sediment. Already a natural habitat. |
Nursery/breeding ground |
Breeding/nursery ground for marine species. |
Breeding/nursery ground for marine species. |
Breeding/nursery ground for marine species. |
Age |
N/A |
Deployed in 2000 |
N/A |
Abundance/Richness of wildlife |
Low |
Moderate |
Low |
Overall Ecological value |
Low-moderate |
Moderate |
Low |
Table 10-6f Ecological value of recognised sites of marine conservation importance within North Western and North Western Supplementary WCZs
Criteria |
Sha Chau and Lung
Kwu Chau Marine Park |
Proposed
|
San Tau Beach SSSI |
Tai Ho Stream SSSI |
Naturalness |
Natural |
Natural |
Basically Natural |
Basically Natural l |
Size |
1,200 ha |
N/A |
2.7 ha |
5 ha |
Diversity |
Moderate |
Moderate |
Moderate |
High |
Rarity |
One of the two most important sea areas for CWD in Hong Kong |
One of the two most important sea areas for CWD in Hong Kong |
San Tau harbours the largest seagrass area on Lantau; one of the three recognized horseshoe crab nursery sites Hong Kong. |
Support the greatest diversity of fresh water and brackish-water fish in Hong Kong. |
Re-creatability |
Not re-creatable. |
Not re-creatable. |
Not re-creatable. |
Not re-creatable. |
Fragmentation |
Unfragmented. |
Unfragmented. |
Unfragmented. |
Unfragmented. |
Ecological linkage |
Generally linked with the open sea |
Generally linked with the open sea. |
Connect to soft shore habitats along the channel |
Generally linked with the open sea. |
Potential value |
Low. Already a natural habitat. |
Low. Already a natural habitat. |
Low. Already a natural habitat. |
Low. Already a natural habitat. |
Nursery/breeding ground |
Nursery ground for CWD. |
Nursery ground for CWD.. |
Nursery ground for horseshoe crab |
Nursery ground for horseshoe crab |
Age |
N/A |
N/A |
N/A |
N/A |
Abundance/Richness of wildlife |
High for CWD |
High for CWD |
Moderate |
High |
Overall Ecological value |
High |
High |
High |
High |
10.4.4.2 Based upon the evaluation, discussions are concentrated on the habitats that are simultaneously more important to the species/habitats of conservation importance and relevant to the Project.
10.4.4.3 West Lantau and North Lantau waters which are the most important dolphin habitats in Hong Kong. The CWD are present commonly year-round in the waters north and west of Lantau, and are found only seasonally or rarely in other places of Hong Kong.
10.4.4.4 In accordance with Table 3, Annex 8 of the EIAO-TM, the ecological value of species was assessed in terms of:
· Protection status;
· Species distribution; and
· Rarity.
10.4.4.5 12 floral species of conservation interest have been identified. Eight species were identified in both EBS and EVS studies, while sedge Carex tristachya and orchid Arundina chinensis were not recorded in the EVS. These two species were previously recorded in tall shrubland and shrubby grassland. Among them, three species of seagrasses are considered relevant to the impact assessment as they colonise intertidal zone and potentially subject to water quality impacts.
10.4.4.6 A total of 51 faunal species of conservation interest or restricted range, based on Fellowes et al. (2002), IUCN redlist, China Redlist, and Hong Kong legislations, have been recorded during the EBS and EVS. Among them, a total of 22 fauna species of conservation concern is considered relevant to the impact assessment of this Project, as they were recorded in habitats potentially subject to direct or indirect impacts from the HKLR and HKBCF, including marine mammal, wetland dependent birds, terrestrial fauna recorded in Scenic Hill, soft shore intertidal fauna.
10.4.4.7 This project would only affect limited area of terrestrial habitats within the terrestrial study area. In addition, terrestrial habitats would be affected are mainly disturbed/developed areas, which are of low ecological importance. Most terrestrial fauna of conservation concern were recorded at locations distant from the proposed alignment. Therefore not all the 51 fauna species utilize the habitats relevant to the Project. Only 22 species are considered relevant to the impact assessment.
10.4.4.8 The proposed alignment would span over coastal waters. Therefore, fauna relevant to the impact assessment for the Project are those foraging in coastal habitats, in particular avifauna. This included 9 water dependent bird species.
10.4.4.9 Romer’s Tree Frog, though not recorded during the EBS or the EVS, was reported by AFCD in Scenic Hill (Chan et al. 2005b). The proposed alignment would encroach part of the Scenic Hill and potentially disturb the nearby habitats of this endemic frog species. This species is protected under the Wild Animals Protection Ordinance (Cap. 170) and considered of potential global concern. This species is therefore also put into the list of species of conservation concern.
10.4.4.10 Chinese White Dolphin is a Class I protected species in the Mainland. In the SAR, it is protected from capture or direct harm under the Wild Animals Protection Ordinance. The degree of threat to the global population is also ranked as Near Threatened by IUCN World Conservation Union.
10.4.4.11 Of the fauna species of conservation concern within the Assessment Area reported from literature reviews and field surveys, only Pacific Reef Egret mainly forages in coastal habitats. The artificial coastline of Airport Island is not considered to be important habitat of Pacific Reef Egret, due to the deep water and poor food base. More important habitat is present in the inter-tidal mudflats.
10.4.4.12 Though not presently protected under local law, Horseshoe crabs have recently been identified as a species of conservation importance in Hong Kong.
10.4.4.13 Established coral communities of any size are regarded as important habitat types in Hong Kong as defined in Annex 8 of EIAO-TM.
10.4.4.14 The list and evaluation of the floral and faunal species of conservation interest recorded within the Assessment Area, according to the TM-EIAO, are given in Tables 10-7 and 10-8. Relevant species are in bold form.
Table 10-7 Evaluation of floral species of conservation concern within the Assessment Area
Species |
Protection status/China Red Data Book |
Locations/Habitats recorded |
EBS |
EVS |
Rarity |
Relevant to the assessment |
Dwarf
Eel Grass Zostera japonica |
|
San Tau Beach SSSI |
P |
P |
Locally Rare (Hu et al. 2003) |
Potentially subject to water impacts |
Halophila minor |
|
San Tau Beach SSSI |
|
P |
Not previously recorded at San Tau. Locally Rare (Hu et al. 2003) |
Potentially subject to water impacts |
Halophila ovalis |
|
San Tau Beach SSSI |
P |
|
Locally Rare (Xing et al. 2000) |
Potentially subject to water impacts |
Hong
Kong Pavetta Pavetta
hongkongensis |
Cap. 96 |
Tall Shrubland |
P |
P |
Common (Xing et al. 2000) |
No, on North Lantau |
Indian Sundew Drosera indica |
|
Stream (HHW) |
P |
P |
Rare (Xing et al. 2000) |
No, on North Lantau |
Pale Purple Eulophia Eulophia graminea |
Cap. 586; Cap. 96 |
Stone crevices in Stream (HHW) |
P |
P |
Restricted (Siu 2000) |
No, on North Lantau |
Incense Tree Aquilaria sinensis |
Cap. 586; Cap. 96;Near Threatened**; Class II Protected* |
Tall Shrubland, Secondary woodland |
P |
P |
Common (Xing et al. 2000) |
No, on North Lantau |
Portia Tree Thespesia populnea |
|
Coastline, Mangrove associate. |
P |
P |
Limited range; coastal areas (Xing et al. 2000) |
No, on North Lantau |
Clammy Hop Seed Dodonaea viscosa |
|
Coastal habitat (SLW) |
P |
P |
Rare (Xing et al. 2000)
|
No, on North Lantau |
Carex tristachya, |
|
Tall Shrubland (HHW) |
P |
|
Very
rare (Xing et al. 2000) |
No, on |
White-green sedge (Carex leucochlora) |
|
Not in present study |
|
|
Very
rare (Xing et al. 2000) |
No, on |
Bamboo Orchid Arundina chinensis |
Cap. 586; Cap. 96 |
Shrubby grassland |
P |
|
Very Common (Siu 2000); Common (AFCD 2001) |
No, on North Lantau |
* Species relevant to impact assessment are bolded.
Table 10-8 Evaluation of fauna species of conservation concern within the Assessment Area (Species relevant to impact assessment are bolded.)
Species |
Species of Conservation Interest* |
Protection status**/China Red Data Book*** |
Locations/Habitats recorded |
EBS |
EVS |
Rarity**** |
Relevant to assessment |
Mammals |
|||||||
Chinese White Dolphin (Indo-pacific Humpback Dolphin) Sousa chinensis |
- |
WAPO; Cap. 586; CITES App. 1; China Class I protected; IUCN Redlist (Near Threatened) |
Mostly in waters north and west of Lantau, Seasonally in waters south and east of Lantau |
# |
# |
Locally found in western waters, especially the North and West Lantau waters; some 103-193 individuals inhabit Hong Kong waters in various time of the year. |
Yes. Habitat loss and potential water impacts |
Red Muntjac Muntiacus muntjac |
PRC |
WAPO |
Scrubland, Streams |
P |
P |
Widespread (Shek 2004) |
No, on North Lantau |
Birds |
|||||||
Little Grebe Tachybaptus ruficollis |
LC |
- |
Open water |
P |
|
Locally common |
No, not recorded in the EVS |
Grey Heron Ardea cinerea w |
PRC |
- |
Soft Shore; Hard shore |
|
P |
Abundant winter visitor |
Yes. Waterbirds, |
Great Egret Egretta alba w |
PRC (RC) |
- |
Soft Shore; Hard shore |
|
P |
Common to abundant resident |
Yes. Waterbirds, |
Little Egret Egretta garzetta w |
PRC (RC) |
- |
Soft Shore; Hard shore |
|
P |
Abundant resident |
Yes. Waterbirds, |
Pacific Reef Egret Egretta sacra w |
(LC) |
Class II Protected* Rare*** |
Hard Shore |
|
P |
Locally uncommon resident |
Yes. Waterbirds, |
Cattle Egret Bubulcus ibis |
(LC) |
- |
Soft Shore |
P |
|
Uncommon to common resident |
No, on North Lantau |
Chinese Pond Heron Ardeola bacchus |
(LC) |
- |
Hard Shore |
P |
|
Common resident |
No, on North Lantau |
Striated Heron Butorides striatus w |
(LC) |
- |
Intertidal; Streams |
|
P |
Uncommon in summer, scare in winter |
Yes. Waterbirds, |
Black-crowned Night Heron Nycticorax nycticorax w |
(LC) |
- |
Intertidal; Streams |
|
P |
Common to abundant resident |
Yes. Waterbirds, |
Black Kite Milvus migrans |
(RC) |
Class II Protected* |
Overhead |
|
P |
Abundant winter visitor and resident |
No, |
Peregrine Falcon Falco peregrinus |
LC |
- |
Overhead |
P |
|
Scare resident and winter visitor |
No, not recorded in the EVS. |
Black-winged Stilt Himantopus himantopus |
RC |
- |
Soft Shore |
P |
|
Common to uncommon winter visitor |
No, not recorded in the EVS. |
Little Ringed Plover Charadrius dubius w |
(LC) |
- |
Soft Shore |
|
P |
Locally common winter visitor, scarce breeding. |
Yes. Waterbirds, |
Whimbrel Numenius phaeopus w |
LC |
- |
Soft Shore |
|
P |
Common passage migrant |
Yes. Waterbirds, |
Grey-tailed Tattler Heteroscelus brevipes w |
LC |
- |
Soft Shore |
|
P |
Passage migrant |
Yes. Waterbirds, |
Eurasian Woodcock Scolopax rusticola |
LC |
- |
Secondary Woodland |
P |
|
Scare winter visitor |
No, not recorded in the EVS. |
Collared Scops Owl Otus bakkamoena |
- |
Class II Protected* |
Tall Shrubland |
|
P |
Common and widespread resident |
No, on North Lantau |
Pacific Swift Apus pacificus |
(LC) |
- |
Overhead |
P |
|
Common spring migrant, localized summer visitor, scarce and irregular in autumn and winter |
No, not recorded in the EVS. |
White-throated Kingfisher Halcyon smyrnensis |
(LC) |
- |
Soft Shore, Hard Shore |
P |
|
Resident, locally common in autumn and winter |
No, not recorded in the EVS. |
Emerald Dove Chalcophaps indica |
- |
Near Threatened**; Vulnerable*** |
Tall Shrubland |
|
P |
Scarce but widespread resident |
No, on North Lantau |
Hwamei Garrulax canorus |
- |
Near Threatened** |
Shrubland |
|
P |
Common and widespread resident |
No, on North Lantau |
Blyth’s Leaf Warbler Phylloscopus reguloides |
LC |
- |
Shrubland |
|
P |
Scarce winter visitor
|
No, on North Lantau |
Common Rosefinch Carpodacus erythrinus |
LC |
- |
Village/farmland |
|
P |
Rare winter visitor |
No, on North Lantau |
Red-billed Starling Sturnus sericeus |
GC |
- |
Coastal habitat, secondary woodland |
|
P |
Abundant but localized winter visitor |
No, on North Lantau |
White-shouldered Starling Sturnus sinensis |
(LC) |
- |
Village/farmland |
|
P |
Common passage migrant, scare and localized breeding summer visitor and winter visitor |
No, on North Lantau |
Black-naped Oriole Oriolus chinensis |
LC |
- |
Plantation |
|
P |
Scarce autumn migrant and irregular breeder |
No, on North Lantau |
Brown Fish Owl |
|
|
Tai Ho Stream |
|
|
Rare |
No, at Tai Ho on North Lantau |
Reptiles |
|
|
|
|
|
|
|
Tokay Gecko Gekko gecko |
RC |
- |
San Tau Village |
P |
|
Rare (Karsen et al. 1998)
|
No, on North Lantau |
Amphibians |
|||||||
Chinese Bullfrog Hoplobatrachus chinensis |
PRC |
IUCN Least Concern Class II Protected* |
Scenic Hill – concrete drainage system |
|
P |
Fairly common and widespread in NT and Lantau (Chan et al. 2005) |
Yes, at Scenic Hill |
Lesser Spiny Frog Paa exilispinosa |
GC |
IUCN Vulnerable |
Streams |
P |
P |
Common & Widespread in protected areas (Chan et al. 2005). |
No, on North Lantau |
Romer’s Tree Frog Philautus romeri |
PGC |
IUCN Endangered |
Literature review and AFCD (Pers. comm.) |
|
|
Endemic to Hong Kong. Locally Common in protected areas (Chan et al. 2005) |
Yes, at Scenic Hill |
Fish |
|||||||
Beijiang Thick-lipped Barb Acrossocheilus beijiangensis |
GC |
- |
Stream (ST9) |
|
P |
Rare (Lee et al. 2004) |
No, on North Lantau |
Indo-Pacific Tropical Sand Goby Favonigobius reichei |
- |
IUCN Lower Risk/Near Threatened |
Estuaries of Streams (ST9, HH5, SL3) |
|
P |
Common and widespread (Lee et al. 2004, Nip 2005) |
Potentially subject to water impacts |
Dark-margined Flagtail Kuhlia marginata |
RC |
- |
Stream (ST9) |
|
P |
Status
unknown (Lee et al. 2004) |
No, on |
Rice Fish Oryzias curvinotus |
GC |
- |
Stream (ST9, HH3, HH5) |
|
P |
Uncommon (Lee et al. 2004) |
No, on North Lantau |
Predaceous Chub Parazacco spilurus |
- |
Vulnerable*** |
Stream (ST9, SL3) |
|
P |
Common and widespread (Lee et al. 2004) |
Potentially subject to water impacts |
Snowy Puffer Takifugu niphobles |
- |
IUCN “Data Deficient” |
Soft Shore (San Tau) |
|
P |
Considered to be common in Hong Kong (AFCD 2008). |
Potentially subject to water impacts |
Takifugu ocellatus |
LC |
- |
Stream (ST9) |
P |
|
- |
No, on North Lantau |
Butterflies |
|||||||
White Dragontail Lamproptera curius |
LC |
- |
Stream At San Tau (ST9)) |
|
P |
Limited Distribution (Lo 2005) |
No, on North Lantau |
Common Albatross Appias albina |
LC |
- |
Cultivated field at San Tau |
P |
|
Rare (Lo 2005) |
No, on North Lantau |
Danaid Eggfly Hypolimnas misippus |
LC |
- |
Shrubland at Scenic Hill |
P |
|
Uncommon (Lo 2005) |
Yes, at Scenic Hill |
Crustaceans |
|||||||
Sesarmine Crab Chiromantes sereni |
- |
- |
Stream (HH3, SL3) |
|
P |
Endemic. Only known from four sites(Kwok & Tang 2005) |
No, on North Lantau |
Greasyback Shrimp Metapenaeus ensis |
- |
Vulnerable*** |
Stream (ST9, SL3) |
|
P |
Found on sandy-mud or muddy bottoms. Major species cultivated at Mai Po Marshes Nature Reserve (AFCD 2004) |
Potentially subject to water impacts |
Freshwater Crab Somanniathelphusa zanklon |