This section of the EIA report presents an assessment of the potential impacts on the terrestrial and marine ecological resources associated with the proposed Project. The Project (as described in Section 2) will include the construction of towers, terminals, angle stations and an emergency rescue trail for the proposed Cable Car System. The assessment follows the methodology set out in Annexes 8 and 16 of the Technical Memorandum on the Environmental Impact Assessment Process (TMEIA).
The Study Brief (ESB 068/2001) requires that an ecological impact assessment is carried out to examine the flora, fauna and other components of the ecological habitats within the assessment area, including the Lantau North Country Park and proposed Lantau North (Extension) Country Park. The Study Brief states that the assessment area for the ecological impact assessment should cover 500m from the project boundary and shall identify and quantify, as far as possible the potential ecological impacts associated with the project, including the potential impacts from human disturbance on the sensitive ecological habitats at Ngong Ping area and any impacts of haul roads and temporary access.
Discussions have been held with Green Groups (Conservancy Association, Friends of the Earth, Green Lantau Association, Kadoorie Farm and the Worldwide Fund for Nature Hong Kong) and government departments as part of this assessment and the comments have been taken into account in the development of practical solutions and the Nature Conservation Policy (refer to Annex F – Part A).
This section describes the baseline ecology of the Study Area, predicts and evaluates potential ecological impacts and recommends mitigation measures where appropriate. The objectives of the this section are to:
· establish an ecological baseline for the Study Area, focusing on identifying key areas and key species present;
· assess the ecological impacts of the cable car alignment;
· develop feasible and effective mitigation measures for significant impacts;
· determine whether residual, post mitigation impacts are acceptable; and
· assess the post mitigation acceptability of the alignment
Government legislation, guidelines and international agreements relevant to the consideration of terrestrial and aquatic ecology under this study include the following:
1. Animals and Plants (Protection of Endangered Species) Ordinance (Cap 187);
2. Country Parks Ordinance (Cap. 208) and associated subsidiary legislation;
3. Environmental Impact Assessment Ordinance (Cap 499), the associated TMEIA (Annex 8 and Annex 16) and Guidance Notes;
4. Forests and Countryside Ordinance (Cap. 96) and its subsidiary legislation the Forestry Regulations;
5. Town Planning Ordinance (Cap. 131);
6. Wild Animals Protection Ordinance (Cap. 170);
7. Environment, Transport and Works Bureau Technical Circulars
a. Works Bureau Technical Circular No. 14/2002 on Management and Maintenance of Natural Vegetation and Landscape Works, and Tree Preservation; and
b. Works Branch Technical Circular No. 4/97 (Planning, Environment and Lands Branch Technical Circular No. 1/97) Guidelines for Implementing the policy on Off-site Ecological Mitigation Measures;
8. Hong Kong Planning Standards and Guidelines, Chapter 10 ‘Conservation’;
9. Sites of Special Scientific Interest Register;
10. Convention on International Trade in Endangered Species of Wild Flora and Fauna (CITES);
11. Convention on the Conservation of Migratory Species of Wild Animals (the Bonn Convention);
12. Convention on Wetlands of International Importance Especially as Waterfowl Habitat (the Ramsar Convention);
13. United Nations Convention on Biodiversity (1992);
14. China and Australia Migratory Bird Agreement (CAMBA);
15. Agreement on the protection of Migratory Birds and their Habitats by the Governments of Japan and the PRC;
16. Asia-Pacific Migratory Waterbird Conservation Strategy: 2001-2005
17. IUCN Red Data Books; and
18. PRC Wild Animal Protection Law.
Animals and Plants (Protection of Endangered Species) Ordinance
The purpose of the Animals and Plants (Protection of Endangered Species) Ordinance is to restrict the import and export of scheduled species. The Ordinance is primarily related to controlling trade in threatened and endangered species and restricting the local possession of them.
Country Parks Ordinance
The Country Parks Ordinance provides for the designation and management of Country Parks and Special Areas. Country Parks are designated for the purpose of nature conservation, countryside recreation and outdoor education. Special Areas are created mainly for the purpose of nature conservation.
Environmental Impact Assessment Ordinance, the associated TMEIA (Annex 8 and Annex 16) and Guidance Notes
The Environmental Impact Assessment Ordinance (EIAO) was implemented on 1 April 1998. Its purpose is to avoid, minimise and control the adverse impact on the environment of designated projects, through the application of the EIA process and the Environmental Permit (EP) system.
Annex 16 of the TMEIA sets out the general approach and methodology for assessment of ecological impacts arising from a project or proposal, to allow a complete and objective identification, prediction and evaluation of the potential ecological impacts. Annex 8 lists the criteria that can be used for evaluating ecological impacts.
EIAO Guidance Note No. 6/2002 Ecological Assessment
The guidance note elaborates on Annexes 8 and 16 of the TM to clarify the requirements for ecological assessment.
EIAO Guidance Note No. 7/2002 Ecological Baseline Survey For Ecological Assessment
The guidance note elaborates on Annex 16 of the TM to provide information on the requirements of ecological baseline study. The note provides general guidelines for conducting an ecological baseline survey in order to fulfil the requirements stipulated in the TM in respect of ecological assessment for a proposed development.
Forests and Countryside Ordinance
The Forests and Countryside Ordinance prohibits felling, cutting, burning or destroying of trees and growing plants in forests and plantations on Government land. The subsidiary Forestry Regulations prohibit the picking, felling or possession of listed rare and protected plant species. The list of protected species in Hong Kong (under the Forestry Regulations) listed in Section 3 of the Forests and Countryside Ordinance (was last amended on 11 June 1993 under the Forestry (Amendment) Regulation 1993).
Town Planning Ordinance
The Town Planning Ordinance provides for the designation of Conservation Areas, Coastal Protection Areas, Sites of Special Scientific Interest (SSSIs), Green Belt or other specified uses that promote conservation or protection of the environment. The authority responsible for administering the Town Planning Ordinance is the Town Planning Board.
Wild Animals Protection Ordinance
The Wild Animals Protection Ordinance protects designated wild animals from being hunted, and their nests and eggs from destruction and/or removal. All birds and most mammals including all cetaceans (i.e. whales, dolphins and porpoises) are protected under this Ordinance, as well as certain reptiles, amphibians and invertebrates. The Schedule Two of the Ordinance lists protected animals (last revised in June 1992).
Environment, Transport and Works Bureau Technical Circulars
Works Bureau Technical Circular No. 14/2002 Management and Maintenance of Natural Vegetation and Landscape Works, and Tree Preservation
This Circular defines the management and maintenance responsibilities for natural vegetation and landscape works, including both softworks and hardworks, and the authorities for tree preservation and felling. This Circular has the agreement of the Secretary for the Environment and Food, the Secretary for Home Affairs, the Secretary for Planning and Lands and the Director of Housing.
Works Branch Technical Circular No. 4/97 (Planning, Environment and Lands Branch Technical Circular No. 1/97) Guidelines for Implementing the policy on Off-site Ecological Mitigation Measures
This circular sets out guidelines for the implementation of the Government’s policy on off-site ecological mitigation measures which, in brief, requires that where such a measure is required, it would be provided to the extent that it is practicable, on a ‘like for like’ basis and within the boundaries of Hong Kong.
Hong Kong Planning Standards and Guidelines, Chapter 10 ‘Conservation’
HKPSG (Chapter 10) covers planning considerations relevant to conservation. Chapter 10 details the principles of conservation, the conservation of natural landscape and habitats, historic buildings and archaeological sites. It also addresses the issue of enforcement. The appendices list the legislation and administrative controls for conservation, other conservation related measures in Hong Kong, and Government departments involved in conservation.
Sites of Special Scientific Interest Register
A Sites of Special Scientific Interest (SSSI) is designated according to the site's special faunal, floral, ecological or geographical features. SSSIs are designated for protection under the Town Planning Ordinance. These are less well protected than country parks and are not actively managed. A register of sites is held by Agriculture, Fisheries and Conservation Department.
Convention on International Trade in Endangered Species of Wild Flora and Fauna (‘CITES’)
CITES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora) is an international agreement between Governments. Its aim is to ensure that international trade in specimens of wild animals and plants does not threaten their survival.
Convention on the Conservation of Migratory Species of Wild Animals (the ‘Bonn Convention’)
The Convention on the Conservation of Migratory Species of Wild Animals (also known as CMS or the Bonn Convention) aims to conserve terrestrial, marine and avian migratory species throughout their range. It is one of a small number of intergovernmental treaties concerned with the conservation of wildlife and wildlife habitats on a global scale.
The Convention on Wetlands, signed in Ramsar, Iran, in 1971, is an intergovernmental treaty, which provides the framework for national action and international co-operation for the conservation and wise use of wetlands and their resources. There are presently 133 Contracting Parties to the Convention, with 1224 wetland sites, totalling 105.8 million hectares, designated for inclusion in the Ramsar List of Wetlands of International Importance.
United Nations Convention on Biological Diversity of 1992
The Peoples’ Republic of China (PRC) is a Contracting Party to the United Nations Convention on Biological Diversity of 1992. The Convention requires signatories to make active efforts to protect and manage their biodiversity resources. The Government of the Hong Kong Special Administrative Region has stated that it will be ‘committed to meeting the environmental objectives’ of the Convention (PELB, 1996).
China and Australia Migratory Bird Agreement (CAMBA)
The PRC is a signatory to the 1986 China-Australia Migratory Birds Agreement (CAMBA). Among other things, the agreement requires that consideration be given to habitat conservation. The two countries are developing a Migratory Waterbird Conservation Strategy.
Agreement on the protection of Migratory Birds and their Habitats by the Governments of Japan and the PRC
The PRC is a signatory to the 1981 Agreement on the protection of Migratory Birds and their Habitats. The agreement requires that consideration be given to the protection of migratory species bwteen China and Japan.
Asia-Pacific Migratory Waterbird Conservation Strategy: 2001-2005
The Strategy aims to enhance the long-term conservation of migratory waterbirds and their habitats in the Asia-Pacific region. The Strategy calls for action to be undertaken at the international, regional and national level. An international consultative committee - the Asia-Pacific Migratory Waterbird Conservation Committee (MWCC) oversees the promotion and implementation of the Strategy. The State Forestry Administration, PRC is one of 16 members of the MWCC.
IUCN Red Data Books
The IUCN Data Books (and Red List)is an inventory of the global conservation status of plants and animals. It uses a set of criteria to evaluate the extinction risk of species. These criteria are relevant to all species and regions of the world.
PRC Wild Animal Protection Law
The PRC in 1988 ratified the Wild Animal Protection Law of the PRC, which lays down basic principles for protecting wild animals. The Law prohibits killing of protecting animals, controls hunting, and protects the habitats of wild animals, both protected and non-protected. The Law also provides for the creation of lists of animals protected at the state level, under Class I and Class II. There are 96 animal species in Class I and 156 in Class II. Class I provides a higher level of protection for animals considered to be more threatened.
A Conservation Strategy for Lantau (Green Lantau Association) is a voluntary sector paper, which identifies priorities for conservation on Lantau and surrounding islands and the main biodiversity resources of Lantau. The strategy has been used a guide for predicting and evaluating ecological impacts and the avoidance, minimisation and mitigation of impacts.
The ecological assessment of the proposed cable car alignment and the Study Area has been based on a number of ecological investigations outlined below.
1. Agreement No. CE 1/97 Remaining Development in Tung Chung and Tai Ho Comprehensive Feasibility Study Working Paper No. WP10, Review of Cable Car Proposal (Mott Connell Ltd, 1998)
A preliminary ecological assessment which highlighted the ecological concerns of the Project including implications for the Country Park and ecological impacts during construction and operation for proposed alignment options. This Study evaluated impacts associated with each of six alignment options and Project alternatives.
2. Consultancy Agreement NEX/034 Tung Chung Cable Car Feasibility Study: Final EIA Report (Mott Connell Ltd, 1999)
A detailed ecological assessment, which discusses the ecological implication of constructing and operating a Cable Car route between Tung Chung and Ngong Ping. Based on field surveys conducted from July to October 1999 and a literature review, existing baseline ecological conditions of the site are described and the key ecological resources of the area highlighted. Potential ecological impacts arising from the proposed cable car are identified and their significance evaluated.
3. Agreement No. HKI 1/2002 Tung Chung Cable Car Project: Ecological Baseline Survey
A detailed ecological baseline survey, based on the final proposed alignment (and associated infrastructure). This report presents the findings of a literature review and focused field surveys that were undertaken within the Study Area from May 2002 to January 2003. BMT Asia Pacific Limited (BMT) were commissioned by the Territory Development Department (TDD) to undertake an Ecological Baseline Survey on the 9th May 2002 for the proposed Project.
4. Rapid surveys of selected tower locations, helicopter touch down points and the proposed emergency rescue route (Mott Connell Ltd, November/ December 2002)
Field surveys carried out by Mott Connell ecologists at selected locations and minor modifications to tower locations.
These reports review literature of ecological resources within and in proximity to the Study Area, which guided survey methodologies and fieldwork locations. Key documents and publications that were primarily reviewed for information on flora and fauna include:
· Agreement No. CE 1/97 Remaining Development in Tung Chung and Tai Ho Comprehensive Feasibility Study Working Paper No. WP10, Review of Cable Car Proposal (Mott Connell Ltd, 1998);
· Consultancy Agreement NEX/034 Tung Chung Cable Car Feasibility Study: Final EIA Report (Mott Connell Ltd, 1999);
· Agreement No. HKI 1/2002 Tung Chung Cable Car Project: Ecological Baseline Survey;
· Porcupine! – Newsletter of the Department of Ecology and Biodiversity, The University of Hong Kong;
· Memoirs of the Hong Kong Natural History Society;
· Agreement No. CE 29/2001: Outlying Islands Sewerage Stage 1, Phase 1 – Ngong Ping Sewage Treatment Works and Sewerage Investigation, Design and Construction: Final EIA Study Report, Volume I (Ove Arup and Partners, 2002);
· North Lantau Development Topic Report TR 10 Environmental Assessment (Mott MacDonald Ltd., et al., 1991); and
· Proposed Report Development at Ngong Ping, Lantau Island: Ecological Assessment (Ecoschemes Asia Ltd., 1997).
The focused field survey methodologies adopted for the baseline study are presented below under the following sub-headings (BMT, 2002). Mott Connell conducted additional vegetation surveys in December and November 2002 to supplement the baseline study.
Figure 7.1illustrates the Study Area and field survey locations.
The vegetation survey adopted the use of 25m2 plots marked around each of the cable car pylon locations, the Angle Station and the Ngong Ping terminal to allow a profile of the vegetation communities to be generated. Survey locations were accurately determined using grid-coordinates of each location and a Global Positioning System (GPS). Figure 7.1 displays the survey co-ordinates. Mott Connell conducted vegetation surveys of the touch down-point locations, emergency access trail and habitat adjacent to Tower 5 as shown on Figure 7.1.
Parameters recorded at each survey plot included species richness and abundance (estimated percentage cover). All higher plants encountered were identified to species level and their conservation status has been reported according to Xing et al. (2000). The location and habitat character of all rare and protected plant species encountered was noted.
A Habitat Map illustrating the broad vegetation groupings in the Survey Area has been prepared using information from direct field observations, ground level photography, aerial photographs from the Lands Department and an indicative habitat map prepared for the Cable Car Feasibility Study (refer to Figure 7.3).
Preliminary vegetation surveys took place in July 2002 and detailed vegetation surveys were conducted in September and October 2002.
Direct and indirect observations of mammals were made along the general alignment and amongst the vegetation/ tracks either side of the alignment within the Survey Area. Due to the generally open habitat of much of the Survey Area the survey effort focussed more on areas of dense vegetation that provide shelter/ refuge to various land mammals known to inhabit the general environs. Observations were also made for bats and for nocturnal activity of ground mammals.
Observations of mammals were made through a combination of day time and night-time survey utilising visual sightings and indirect observations of activity, e.g. tracks, droppings and signs of feeding damage (such as stripped bark from trees).
Mammal surveys were conducted on the following dates: 19th May; 6th June; 26th June; 3rd August (night time); 10th September; 25th September; 5th October (night time) and 17th December 2002. Incidental mammal observations were made on 28th May and 1st July 2002.
The survey approach for the herpetofauna (reptiles and amphibians) was to identify suitable habitats that fall in close proximity of the preferred alignment and other suitable habitats that are adjacent to the alignment but still located within the Study Area. Habitats selected for investigation included hill streams and pools, freshwater springs, and dry habitat such as woodland litter (including seasonal stream areas) and rock outcrops.
The presence of these groups was investigated during daytime and night time. Where appropriate, binoculars were initially used to scan the area from distance to determine specimen presence. This enabled a hidden approach towards the habitat/ species to be planned so as to avoid disturbance, thereby maximising the observation success. A net was used to catch amphibians where initial visual observation was insufficient. Noise from reptile movement over dry habitats (e.g., leaf litter) during the survey was particularly useful during dry season months.
Amphibian and reptiles surveys were undertaken on the following dates: 19th May; 6th June; 26th June (night time); 31st July (night time); 3rd August (night time); 21st September; 25th September; 5th October (night time); 6th November and 17th December 2002. Incidental observations were made on the 28th May 2002.
Species of butterfly and dragonfly in the Study Area were determined by direct observations made along the preferred alignment and in similar adjacent areas within the Study Area. The survey work was generally conducted in dry weather, or shortly after rainfall.
All butterflies and dragonflies were identified to species level, and their status noted according to Wilson (1997) for dragonflies and Young and Chung (2001) for butterflies. Parameters recorded include species type, abundance and location observed. For butterflies of particular conservation importance, a note was made of the vegetation type where appropriate.
Insect surveys were undertaken on the following dates: 6th June; 26th June; 3rd August; 24th August; 10th September; 25th September; 5th October; 27th October; 28th November; 14th December and 17th December 2002.
A line-transect survey covering the major habitat types (i.e. grassland, short and tall shrub, and woodland) along a freely accessible route through the Study Area was chosen. All birds seen with binoculars (10 x 42 Leica) and heard were logged by species type and number of individuals observed in each habitat. A recording proforma was used throughout the survey.
Bird surveys commenced close to dawn (typically starting around 5 a.m.) to coincide with peak activity of most bird species.
Bird surveys were undertaken on the following dates: 28th May, 15th August; 14 October; 27th November; 14th December 2002 and 11 January 2003.
Stream Survey primarily involved investigation of freshwater fish and macroinvertebrates. It was found that stream substrate was generally of limited value for macroinvertebrate kick-survey (disturbance of stream habitat and dislodgement of invertebrates captured by net). A combination of systematic and non-systematic ‘walk-through’ methods was adopted.
Observations of infauna were generally made in-situ, underneath stones on the stream banks and in pools. Fish were caught using a hand-net, identified in-situ and then released. Where in-situ identification was not possible, the key identification features of the fish were recorded to allow for later identification.
Stream surveys were undertaken on the following dates: 6th June; 24th August; 25th September; 28th November and 14th December 2002. Incidental observations of stream fish were made on the 17th December 2002.
Survey of inter-tidal habitats, including mangrove, mudflat and seagrass communities was undertaken using a line transect between the backshore and the low-water level at San Tau and at Tung Chang mangal.
Inter-tidal mangrove/ sand and mudflat habitats were surveyed using a series of 25cm2quadrats placed at different shoreline zones (visually determined). For each quadrat the epifauna was identified to the lowest taxa possible and quantified.
The mangrove habitats at Tung Chung and San Tau was qualitatively assessed against that described by Tam and Wong (1997).
The shallow sub-tidal benthic infauna community was investigated at selected locations at low water using a hand trowel and sieve. Investigations were supplemented with observations of human shellfish harvesting activity that was popular across the Tung Chung Bay sandflats at low water.
A survey of fisheries resources in and around Tung Chung Bay was conducted by visual observations. This was supplemented by interviews with and observations of the catch of recreational/ commercial ‘fishermen’.
During the course of the baseline survey it was confirmed by MTRC that there would be no tower placement within coastal waters of Tung Chung Bay. Accordingly, the study programme was refined and effort was refocused upon terrestrial habitats.
Coastal surveys were undertaken on the following dates: 26th June; 1st July and 11th July 2002.
For the purpose of the EIA Study, important conservation sites are considered as potential sensitive receivers, particularly where species of conservation value/ sensitivity are known to utilise them. In this regard, consideration of species movements within the Study Area needs to be taken into account.
Sites within or in the vicinity of the Study Area that are specifically designated for their conservation importance are discussed below. Although the sites discussed as follows have a specific conservation value that has been recognised by their designation, the broader area around Tung Chung valley is known to be of conservation value (PlanD, 1993).
It should be noted that investigation into the feasibility of designating new Site(s) of Special Scientific Interest (SSSI’s) is an on-going process, although AFCD confirmed that there are no proposals for new SSSI’s in the vicinity of the Study Area.
The Lantau South Country Park (LSCP) and Lantau North Country Park (LNCP) were designated in April and August 1978, respectively. LSCP is the largest Country Park in the HKSAR, covering an area of over 5,600ha. The LNCP covers an area of approximately 2,200 ha. Together these Country Parks cover most of the land area of Lantau.
Covering much of the northern portion of the Study Area is the potential Lantau North (Extension) Country Park that was identified in the 1993 Territorial Development Strategy Review (PlanD, 1993). The proposed Lantau North (Extension) Country Park was gazetted under Country Parks Ordinance in July 2001 and its designation is being considered by the CE in council (pers comm. AFCD, 2003).
The San Tau Beach SSSI was designated in October 1994 by virtue of the diverse mangrove/ mangrove associate community and an area of seagrass habitats. San Tau is the only known location on Lantau for Halophila minor and Zostera japonica, and the principal reason for SSSI designation.
Ngong Ping SSSI was designated in May 1999 as its seasonal wooded streams provided habitat for the endemic and rare Romer’s Tree Frog Philautus romeri. This SSSI is in an area located outside the Country Park.
The Lantau Peak Special Area, which covers 116 hectares (ha), was designated in January 1980 by virtue of the high diversity and conservation value of the native woodland and associated flora and fauna that can be found on the lower slopes.
Lantau Peak SSSI covers an area of 227.5 ha and overlaps with the Special Area to some extent. The SSSI was approved in February 1980 due to its remarkable shrub/ tree flora that includes rare species such as Exbucklandia spp., Magnolia spp., Manglietia spp. and Illicium spp.
Both the Lantau Peak Special Area and SSSI are entirely within the existing Lantau South Country Park.
By virtue of its diverse native woodland, in June 1976 Sunset Peak was the first SSSI in proximity to the Study Area to be designated as a site of conservation interest. Of note at the SSSI are the rare species Amentotaxus argotaenia, Manglietia fordiana and Meliosma squamulata; and the very rare Exbucklandia tonkinensis.
The Sunset Peak Special Area was designated at the same time as that for Lantau Peak (January 1980) due to the high diversity and conservation value of the native woodland and associated flora / fauna that can be found on its mid and lower slopes.
This SSSI constitutes two adjacent wooded areas and was designated in August 1994 due to its excellent example of undisturbed montane shrub forest that forms a continuum with the lower and mid northern slopes of Sunset Peak. The SSSI supports over 200 native plant species, including a number of rare and protected species such as Asarum hongkongense.
The general upland core of Lantau Island around Sunset and Lantau Peaks, and the lower and mid slopes to the north, are known to contain diverse areas of flora in the HKSAR. The entire Tung Chung valley area to the east of Tung Chung Road and stream is considered to be of high botanical importance (PlanD, 1993).
Most of the designated sites of conservation importance in proximity to the Study Area have been so designated by virtue of their unique assemblages and/ or good examples of undisturbed floral communities. Since the designation of the various sites of botanical importance there continue to be new records of flora in these and nearby areas. Recent examples include the finding in February 2001 of the locally restricted sub-shrub Smilax aberrans in ravine forest at Sunset Peak (Ng, 2001); and findings of various rare Cyperaceae in recent years, such as Carex canina, C. tenebrosa and Scleria corymbosa at Sunset Peak; Carex nexa at Nei Lak Shan (Shaw, 2001); and Carex fenghuangshanica at San Tau.
The vegetation survey conducted by Mott Connell (2002) at Tung Chung West for the ‘Comprehensive Feasibility Study’ included a survey of Fung Shui woodland at San Tau that falls within the Study Area for this Project. It was reported that the San Tau woodland covers 4 hectares and supported 94 species of flora including (according to Xing et al, 2000) four species of restricted distribution: Cansjera rheedii, Erycibe obtusifolia, Vitis balansaeana and Celtis timorensis. In the coastal scrub habitat off the path between San Tau and Tung Chung (and over which the cable car alignment passes) the rare shrub Uvaria calamistrata and two restricted species (Scleria lithosperma and Lespedeza cuneata).
The Ngau Au Fung Shui woodland that partly overlaps with the present Study Area nearest to Tung Chung was also surveyed. Species of note recorded here included the restricted tree Litsea monopetala that was one of the dominant canopy species and the restricted Celtis timorensis (ibid.).
The characteristics of each of the habitat types in relation to the cable car alignment are presented under the sub-headings below. Habitat characterisation is based upon the typical assemblage of plant species present and the degree of habitat stratification. Where small streams pass through habitats that are predominantly vegetated, they are included within the ‘vegetated’ habitat type and reference is made to their presence in the text. More open stream courses provide a more distinct habitat type and are categorised separately.
Table 7.1below summarises the type and area of each different habitat type within the Study Area.
Table 7.1 Habitat Type and Approximate Area within the Study Site
|
Habitat Type |
Area (hectares) |
Area (% of total) |
|
Grassland |
262 |
32 |
|
Marsh |
< 0.5 |
< 0.5 |
|
Low shrub |
57 |
7 |
|
Tall shrub |
148 |
18 |
|
Woodland |
105 |
13 |
|
Plantation woodland |
18 |
2 |
|
Cultivation |
1 |
<0.5 |
|
Abandoned cultivation |
4 |
0.5 |
|
Stream |
20km |
- |
|
Mangrove |
0.5 |
<0.5 |
|
Mudflat |
20 |
2.5 |
|
Coastal waters |
110 |
13 |
|
Developed area |
90 |
11 |
|
Total |
820 |
100 |
Source: Adapted from BMT (2002)
In addition, there is approximately 20 km of perennial/ seasonal Streams within the Study Area.
Figure 7.3 displays the habitat map for the entire Study Area and Figure 7.4 presents representative photographs of major habitat types within the Study Area.
The vegetation survey revealed that a total of 134 species of flora were recorded. Vegetation communities have been determined and categorised according to the dominant/ co-dominant species present. This information is presented in Table 7.2.
The vegetation species list is presented in Annex F – Part B.
Table 7.2 Habitat Character at Cable Car Structure Locations
|
Location |
Habitat Type |
Species Richness* |
Key Vegetation Assemblage |
|
Tung Chung Terminal |
Developed |
0 |
No vegetation present |
|
Tower 1 |
Developed |
0 |
No vegetation present |
|
Angle Station |
Developed/ plantation |
25 |
Eupatorium catarium - Lophostemon conferata co-dominant |
|
Tower 2A |
Developed |
0 |
No vegetation present |
|
Tower 2B |
Developed |
0 |
No vegetation present |
|
Tower 3 |
Low shrub |
28 |
Dicranopeteris pedata - Arundinella setosa - Rhodomyrtus tormentosa co-dominant |
|
Tower 4 |
Low shrub |
37 |
Dicranopeteris pedata - Arundinella setosa - Glochidion wrightii co-dominant |
|
Tower 5 |
Low shrub |
21 |
Dicranopeteris pedata dominant |
|
Angle Station |
Grassland |
12 |
Arundinella setosa dominant |
|
Tower 6 |
Grassland |
13 |
Arundinella setosa – Palhinhaea cernum co-dominant |
|
Tower 7 |
Low shrub |
16 |
Dicranopeteris pedata - Arundinella setosa co-dominant |
|
Ngong Ping Terminal |
Low shrub |
27 |
Mikania micrantha - Eupatorium catarium - Synedrella nodiflora - Ligustrium sinense - Cyclosorus parasiticus co-dominant |
|
Helipad locations |
Grassland |
- |
Arundinella setosa dominant |
|
Emergency rescue trail |
Grassland Low Shrub Tall Shrub Woodland |
- |
- |
Source: Adapted from BMT (2002)
Note*: Species richness is the number of different flora species recorded
More specific details of the various habitat types in the Study Area, including dominant and other notable species present, are provided in the following sub-sections.
Much of the upland plateau north out of Ngong Ping and the hilltops and ridges in the Study Area are dominated by grassland habitat that has developed on thin soils formed over hard volcanic bedrock. The vegetation in the vicinity of proposed Angle Station and Tower locations 6 and 7 is predominantly short grass with ferns, herbs and occasional shrub species. Refer to Figure 7.3 (Habitat Map) and Figure 7.4, which presents an image of habitat types within the Study Area.
The species that generally dominate this habitat type are the grasses Arundinella setosa and Rhynchospora rubra, and the fern Dicranopteris pedata. Species that are locally abundant include the ferns Palhinhaea cernum, Lindsaea ensifolia and L. heterophylla, the herb/ subshrub Melastoma dodecandrum and the shrub Rhodomyrtus tormentosa.
A small patch (i.e. 3 flowering stems) of a common orchid Arundina graminiflia (previously known as A. chinensis) was found within 25m south of the proposed angle station location between Pylons 5 and 6. Also, pockets of the very common orchid Arundina graminifolia were seen at a number of locations along the alignment in grassland habitat away from proposed structure locations (refer to Figure 7.2).
Other incidental observations of orchids near the footpath through this habitat (but not near any of the proposed Cable Car structure locations) were Phaius tankervilliae and Habenaria linguella (both restricted); Habenaria dentata (common); and Coelogyne fimbriata, Pholidota chinensis and Spathoglottis pubescens (very common). All orchids are protected under the Forestry Regulations. Table 7.3 evaluates grassland habitat within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum.
Table 7.3 Evaluation of Grassland Habitats within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum
|
Criteria |
Remarks |
|
Naturalness |
The grasslands with the Study Area are natural but modified and are dominated by native species. They are maintained as grasslands by a combination of thin/ infertile soils, erosion and irregular hill fires. |
|
Size |
The grasslands within the Study Area are large and are the largest habitats within the Study Area (32%). |
|
Diversity |
Species diversity for grassland is low. |
|
Rarity |
Grasslands are widespread in Lantau and in the SAR. |
|
Re-creatability |
Grasslands are at the early stage of the vegetation succession and are relatively easily re-created. |
|
Fragmentation |
Continuous sections. |
|
Ecological linkage |
This grassland is probably of medium value for foraging or dispersal for animals of other habitats. |
|
Potential value |
In the absence of hill fires, improved soil conditions and less soil erosion, the hillside grasslands could develop over time into shrubland and then woodlands, which would be of greater ecological value. |
|
Nursery/ breeding ground |
Low. |
|
Age |
Young, relatively recent and regularly re-created as a result of hill fires. |
|
Abundance/ richness of wildlife |
Low. |
|
Summary |
The grasslands within the Study Area are generally evaluated as of low ecological value as a habitat. However, it should be noted that they support a number of rare and/or protected plant species such as orchids, two restricted range birds and one rare, snake. |
There is a small area of marsh habitat approximately 100 metres east from the proposed Tower 6 location that is dominated by the sedge Lepidosperma chinense, a very common grassland species according to Xing et al, 2000. The marsh habitat is expected to be established for a long period, as it is a result of a natural spring. Refer to Figure 7.3 (Habitat Map) and Figure 7.4, which provides an image of habitat types within the Study Area.
Other abundant species at the fringe of this habitat were the grasses Arundinella setosa and Rhynchospora rubra that are common in the surrounding grassland habitat, and the ferns Palhinhaea cernum and Blechnum orientale. On the outer area of the Marsh habitat (the ‘hill’ side) there were an increasing number of shrubland species (‘low shrub’ below refers) were recorded. Table 7.4 evaluates marsh habitat within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum.
Table 7.4 Evaluation of Marsh Habitats within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum
|
Criteria |
Remarks |
|
Naturalness |
The areas of marsh are natural and dominated by native species. |
|
Size |
The marsh habitat within the Study Area is located in one very small area. |
|
Diversity |
Species diversity for marsh is moderate. |
|
Rarity |
Marsh is restricted in Lantau and in the SAR. |
|
Re-creatability |
The marsh is relatively easily re-created from minor disturbances. |
|
Fragmentation |
The marsh present at one location. |
|
Ecological linkage |
Marsh is probably of moderate value for foraging or dispersal for animals of other habitats. The size of the marsh habitat restricts the value to any migratory species. |
|
Potential value |
Likely to be fairly stable providing water regime is maintained. |
|
Nursery/ breeding ground |
Moderate. |
|
Age |
Long established. |
|
Abundance/ richness of wildlife |
Moderate. |
|
Summary |
The marsh within the Study Area is generally evaluated as moderate ecological value as a habitat. |
This habitat type characterises the vegetation communities in the vicinity of proposed Tower locations 3, 4 and 5. The low shrub community predominantly comprises low shrub species (< 1.5m in height) interspersed with the grasses Arundinella setosa and Miscanthus sinensis and the fern Dicranopteris pedata. Refer to Figure 7.3 (Habitat Map) and Figure 7.4 which presents an image of habitat types within the Study Area.
The dominant shrub species in this habitat are Rhodomyrtus tormentosa and Glochidion wrightii, although a number of shrub species are locally abundant. These include: Phyllanthus cochinensis, P. emballica, Desmodium microphyllum, Loropetalum chinensis, Litsea cubeba, L. rotundifolia, Melastoma candidum, M. sanguineum, Ficus hirta, Embelia laeta and Baeckea frutescens.
The ferns Adiantum flabellatum and Humata repens, and the climbers Millettia reticulata, Dalbergia hancei, Cassytha filiformis, Psychotria rubra and P. serpens are also locally abundant.
Species of conservation note recorded in this habitat include a single specimen of Camellia sinensis that was recorded 20m north-west from the proposed Tower 4 location (refer to Figure 7.2). This species is considered rare in the HKSAR. All Camellia species are protected under the Forestry Regulations (Cap. 96).
A total of five uncommon (restricted) species of flora were also noted in this habitat within the footprint of proposed tower locations. Table 7.5summarises these species, their form and location.
Table 7.5 Uncommon Flora in the Low Shrub Community (2002)
|
Species |
Form |
Location |
|
Brainea insignis |
Fern |
Tower 3 |
|
Humata repens |
Fern |
Tower 4 |
|
Loropetalum chinensis |
Shrub |
Tower 4 |
|
Hedyotis pinifolia |
Climber |
Tower 4 |
|
Parathelypteris glanduligera |
Fern |
Tower 5 |
Source: Adapted from BMT (2002)
A second species of Camellia, the restricted Camellia euryoides, was noted in Low Shrub habitat by a stream along the alignment close to Ngong Ping, but not in proximity to any of the Cable Car structures. The Chinese New Year Flower Enkianthus quinqueflorus was recorded at the same area. Although this shrub is protected under the Forestry Regulations it is quite common in shrub habitat in the HKSAR. Neither species would be subject to any direct impact from project development.
Also protected under the Forestry Regulations and common in grassland habitat in the broader area, but not recorded from the Study Area, is the pitcher plant Nepenthes mirabilis. A sizeable colony (approx. 10m2) of this species was encountered in May 2002 in lowland depression slightly northwest of the Study Area (refer to Figure 7.2). Table 7.6 evaluates low shrub habitat within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum.
Table 7.6 Evaluation of Low Shrub Habitats within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum
|
Criteria |
Remarks |
|
Naturalness |
The low shrubland habitats are natural but modified and maintained as Low shrub by thin/infertile soils, erosion, and irregular hill fires. They are dominated by native species. |
|
Size |
The low shrubland areas within the Study Area are of moderate size. |
|
Diversity |
Species diversity is typical for Low shrubland in the area and considered low to medium. |
|
Rarity |
Low shrubland is widespread on Lantau and in the SAR. |
|
Re-creatability |
Low shrublands are at the early stage of the vegetation succession and are relatively easily re-created. |
|
Fragmentation |
This low shrubland is relatively continuous. |
|
Ecological linkage |
This low shrubland is probably of medium value for foraging or dispersal for animals of other habitats. |
|
Potential value |
In the absence of hill fires and with improved soil conditions and less soil erosion the hillside Low shrublands could develop over time into tall shrubland and then woodlands which would be of greater ecological value. |
|
Nursery/ breeding ground |
Low. |
|
Age |
Relatively young and recent and regularly recreated as a result of hill fires. |
|
Abundance/ richness of wildlife |
Low. |
|
Summary |
The low shrub habitats within the study are generally evaluated as of low ecological value. |
Tall shrub habitat is present near the Lin Chi temple at Ngong Ping (below the proposed Tower 7); in deep rills alongside streams in the Ngong Ping plateau area; and more generally on the lower hill slopes throughout the Study Area. Refer to Figure 7.3 (Habitat Map) and Figure 7.4, which presents an image of habitat types within the Study Area.
Amongst the most abundant shrub species are Clerodendrum fortunatum, Eurya chinensis, E. nitida, Glochidion wrightii, Ligustrum sinense, Melastoma candidum, Rhodomyrtus tormentosa and Wickstroemia indica, all common or very common. Young trees that are common in this habitat type include Machilus chekiangensis, Rhus succedeana, Sterculia lanceolata, Schefflera octophylla and Sapium discolor.
Tall shrub is not present within the footprint of any of the proposed Cable Car structure locations. Table 7.7 evaluates tall shrub habitat within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum.
Table 7.7 Evaluation of Tall Shrub Habitats within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum
|
Criteria |
Remarks |
|
Naturalness |
Tall shrub habitats are natural and generally avoid regular burning by hill fires. They are dominated by native species. |
|
Size |
The tall shrub areas within the study are restricted to the more fertile stream valleys and sheltered areas, where soils are more fertile and there is some degree of protection from hill fires. |
|
Diversity |
Species diversity is typical for this area and considered to be moderate to high. |
|
Rarity |
Tall Shrub habitats are relatively restricted in the SAR and are not common on Lantau. |
|
Re-creatability |
Tall shrub is at the later stages of the vegetation succession and are not relatively easily re-created but it can be done over time and with protection from hill fires. |
|
Fragmentation |
This tall shrub habitat is continuous but usually confined to sheltered areas either side of streams and is therefore generally linear. |
|
Ecological linkage |
Tall shrub is probably of high value for foraging and dispersal for animals of other habitats. |
|
Potential value |
In the absence of hill fires with improved soil conditions and less soil erosion, the hillside tall shrub could develop over time into woodlands, which would be of greater ecological value. |
|
Nursery/ breeding ground |
Low |
|
Age |
Relatively mature. |
|
Abundance/ richness of wildlife |
Moderate to high. |
|
Summary |
Tall shrub within the Study Area are generally evaluated as of moderate to high ecological importance as they support a variety of fauna species and rare/ protected plants. |
Native broadleaved secondary woodland is present in three broad areas in the Study Area:
· the downward slopes west of the Ngong Ping plateau;
· the downward slopes east of the Nei Lak Shan ridge to the west of Tung Chung Bay; and
· within the San Tau Valley.
There are also pockets of woodland habitat growing beside tall shrub habitat in upland areas where there are perennial hill streams – most notably around the stream that rises due north of and flows down the west flank of Nei Lak Shan. Refer to Figure 7.3 (Habitat Map) and Figure 7.4, which presents an image of habitat types within the Study Area.
Common species in this habitat type include the trees Machilus chekiangensis, Rhus succedeana, Sterculia lanceolata, Schefflera octophylla and Sapium discolor interspersed with a number of shrub species. There is also a sizeable stand (approx. 0.5 hectares) of the common Chinese Red Pine Pinus massoniana woodland around the lower slopes at the northwest of the Study Area, adjacent to San Tau stream.
This habitat type is not present at the footprint of any of the proposed Cable Car structure locations. Table 7.8 evaluates woodland habitat within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum.
Table 7.8 Evaluation of Woodland Habitats within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum
|
Criteria |
Remarks |
|
Naturalness |
The woodlands are natural and dominated by native species. |
|
Size |
The woodland areas within the Study Area are relatively large. |
|
Diversity |
Species diversity is high for woodland in this area particular in the woodland near San Tau. |
|
Rarity |
Woodlands are relatively restricted in the SAR and are not common on Lantau. |
|
Re-creatability |
Woodlands are at a late stage of the vegetation succession and are not easily re-created. |
|
Fragmentation |
The woodlands within the Study Area are separated but are continuous with other natural shrub habitats. |
|
Ecological linkage |
These woodlands are probably of high value for foraging or dispersal for animals of other habitats. |
|
Potential value |
High, they are moving towards climax vegetation community |
|
Nursery/ breeding ground |
These woodlands provide important feeding grounds for many fauna species, in particular birds and mammals. |
|
Age |
Mature, with some areas established well over 100 years. |
|
Abundance/ richness of wildlife |
These woodlands contain the highest species richness for many groups especially plants, invertebrates and birds. |
|
Summary |
The woodlands within the Study Area are evaluated as of high ecological importance. |
Plantation woodland is present within the Study Area at Ngong Ping and in the vicinity of the angle station at Chek Lap Kok. Both sites comprise a mix of ornamental exotic and native species of trees, shrubs and herbs. Refer to Figure 7.3 (Habitat Map) and Figure 7.4, which presents an image of habitat types within the Study Area.
In addition to the plantation of the protected Camellia sinensis at Ngong Ping, other native species include the common tree Symplocos lancifolia and the shrubs Ligustrum sinense and Rhodomyrtus tormentosa. Exotics at Ngong Ping include the trees Lophostemon conferata, Casuarina equisetifolia and Acacia confusa, the shrub Lantana camara, the herbs Eupatorium catarium and Synedrella nodiflora, and the ubiquitous climber Mikania micrantha. Ove Arup and Partners (2002) also recorded one specimen of the restricted tree Celtis timorensis in plantation at Ngong Ping.
The exotic climber M. micrantha was observed around the village land at Ngong Ping and at similar village/ abandoned cultivation habitat at the Tung Chung end of the alignment. A dense patch of this species was also noted in tall shrub habitat between Tower 3 and Tower 4 locations – likely having been dispersed in bird droppings. The exotic species Lantana camara is also widespread at this location.
At the proposed Chek Lap Kok Angle Station the nearby plantation woodland includes the exotic trees Acacia confusa, Lophostemon conferata, Albizia lebbeck and Pinus elliottii; and a mixed native tree/ shrub community including Rhus hypoleuca, Cratoxylom cochinchinese, Zanthoxylum avicennae and Phyllanthus embalica. Most herbs and grasses present were exotic self-seeded plants except the grass Paspalum sp. that had been hydro-seeded onto the nearby slope area. All species at the proposed Angle Station location are common / very common. Table 7.9 evaluates plantation woodland within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum.
Table 7.9 Evaluation of Plantation Woodland Habitats within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum
|
Criteria |
Remarks |
|
Naturalness |
These plantations were established by man and are artificial. However, some of the plantations at Ngong Ping are becoming more natural over time. There are generally dominated by planted exotic species. |
|
Size |
The plantation areas within the Study Area are relatively restricted |
|
Diversity |
Species diversity is low. |
|
Rarity |
Widespread throughout the SAR. |
|
Re-creatability |
Plantation habitats could easily be created but would need about 20 years to mature to the current stage. |
|
Fragmentation |
The plantation habitats are relatively small and fragmented by paths and houses. |
|
Ecological linkage |
The plantation link areas of natural habitats are probably of medium value for foraging or dispersal for animals of other habitats. |
|
Potential value |
Low but increasing as more native species become established. The monoculture areas dominated by Aciacia confusa are considered to be of low potential value. |
|
Nursery/ breeding ground |
The plantation habitats are not expected to provide anything more than breeding sites for birds. |
|
Age |
Young, relatively recent and regularly re-created as the result of hill fires. The plantations are about 25-30 years old. |
|
Abundance/ richness of wildlife |
Low, these plantation habitats do not contain high species richness for wildlife. |
|
Summary |
The plantations within the Study Area are generally evaluated as of low ecological value but they do support a number of breeding birds on the Ngong Ping plateau and provide a surrounding habitat for the Romer’s Tree Frog. |
There are two areas of active cultivation within the Study Area: Ngau Au along the west of the Tung Chung Stream mouth and at San Tau. Refer to Figure 7.3 (Habitat Map) and Figure 7.4, which presents an image of habitat types within the Study Area.
Species at Ngau Au include various fruit trees including Litchi Litchi chinensis and Longan Dimocarpus longan growing at the edge of the fung shui woodland on the adjacent slope, with mainly Banana Musa paradisiaca and some Papaya Carica papaya and Pomegranite Punica granatum. Ornamental plants that have been grown in this area in the past include lilies and balsalm (Mott Connell, 2000 In BMT, 2002).
The cultivated land at San Tau is set more closely between and around village dwellings and abandoned buildings, thus offering more habitat diversity than can be found at Ngau Au. The adjacent coastal and woodland vegetation affords greater shelter to this area than at the more exposed land at Ngau Au. In addition to supporting the orchard species grown at Ngau Au, a variety of Brassica sp. vegetables, Chinese cucumber Trichosanthes kirilowii, Winter melon Benincasa hispida and gourds are grown in small plots.
Despite an observation of the Common Birdwing butterfly Troides helena near the cultivated land at San Tau, the food plant of this species, Aristolochia tagala that is protected under the Forestry Regulations was not found. Table 7.10 evaluates cultivation habitat within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum.
Table 7.10 Evaluation of Cultivation Habitat within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum
|
Criteria |
Remarks |
|
Naturalness |
The cultivation land is man-made and not considered natural. |
|
Size |
The cultivated areas are restricted to Ngau Au along the west of the Tung Chung Stream mouth and at San Tau. |
|
Diversity |
Species diversity is low for cultivation. |
|
Rarity |
Cultivation is not restricted on Lantau or the HKSAR. |
|
Re-creatability |
Easily re-created. |
|
Fragmentation |
This cultivation is fragmented. |
|
Ecological linkage |
These cultivated habitats are likely to be of limited value for foraging or dispersal for animals of other habitats. |
|
Potential value |
These cultivated lands could scrub up and could develop over time (refer to abandoned cultivated land in Table 7.11). |
|
Nursery/ breeding ground |
Low. |
|
Age |
Young, relatively recent. |
|
Abundance/ richness of wildlife |
Low for cultivation. |
|
Summary |
The cultivation within the Study Area is generally evaluated as of low ecological value. |
Abandoned cultivated land was present at Ngong Ping and is characterised by a flora community of various herb and shrub species. Refer to Figure 7.3 (Habitat Map) and Figure 7.4, which presents an image of habitat types within the Study Area.
Amongst the most abundant species are the common shrubs Eurya chinensis and Ligustrum sinense – widely cultivated species, the very common fern Cyclosorus parasiticus, and the common herbs Eupatorium catarium, Syndrella nodiflora and Alocasia macrorhiza.
Trees in this habitat type include the exotics Lophostemon conferata, Casuarina equisetifolia and Acacia confusa that are common in plantation woodland around Ngong Ping, and the native Machilus chekiangensis that is common in broadleaved woodland in the Study Area.
There were no species of conservation note recorded within this habitat type at the proposed Ngong Ping Terminal location. Table 7.11 evaluates abandoned cultivation within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum.
Table 7.11 Evaluation of Abandoned Cultivation within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum
|
Criteria |
Remarks |
|
Naturalness |
The abandoned cultivation land is man-made but becoming more natural with the cessation of cultivation. |
|
Size |
The abandoned cultivated areas are restricted to the flat lands around San Tau village at the Ngong Ping Terminal. |
|
Diversity |
Species diversity is low to moderate for abandoned cultivation. |
|
Rarity |
Abandoned cultivation is relatively restricted on Lantau and in the SAR. |
|
Re-creatability |
Abandoned cultivation can be similar to grassland and is at the early stage of the vegetation succession and they are relativity easily re-created. |
|
Fragmentation |
This abandoned cultivation is in one continuous zone up the valley. |
|
Ecological linkage |
These abandoned cultivated lands are probably of limited value for foraging or dispersal for animals of other habitats. |
|
Potential value |
These abandoned cultivated lands could scrub up and could develop over time into shrubland and then woodlands, which would be of grater ecological value. However, due to the previous use of soil, this process seems to be slow of previously cultivated land. |
|
Nursery/ breeding ground |
Low. |
|
Age |
Young, relatively recent. |
|
Abundance/ richness of wildlife |
Low to moderate for wet abandoned cultivation (low for dry cultivated land). |
|
Summary |
The abandoned cultivation within the Study Area is generally evaluated as of moderate ecological value. |
There are two main perennial streams for which headwaters flow across the Study Area: Sham Wat Stream (four feeder streams cross the Ngong Ping plateau) and San Tau Stream (the main feeder stream rises in the Study Area between the proposed Angle Station and Tower 5). There is also a relatively short seasonal stream course on the slopes to the northeast of Tower 3 that drains through mixed grassland/ shrub habitat into Tung Chung Bay. Refer to Figure 7.3 (Habitat Map) and Figure 7.4, which presents an image of habitat types within the Study Area.
Of the four Sham Wat Stream feeder streams, the first (SWS 1) is at the proposed site of the Ngong Ping Terminal at around 450m elevation. Most of the length of SWS 1 through the proposed Terminal site is shrubland. There is a short culvert section of SWS 1 where it passes below a village road. From the dark appearance of its water, the fine sediment character and odour from disturbed sediment it is likely that SWS 1 receives waste discharge from the nearby village areas. This observation is supported by discharge from broken sewerage near the Stream and the infauna that characterises this stream.
The other three feeder streams (SWS 2 - 4), at around 500m elevation, are crossed by the existing footpath that follows the approximate alignment almost as far as the Angle Station (refer to Figure 7.3). These three stream are entirely natural and as such the waster quality in these streams is likely to be very good due to the absence of any development/ discharge in the headwaters or middle reaches that flow through the Study Area, This assumption is supported by observations of various stream infauna that characterises this stream.
The vegetation surrounding the upper part of SWS 2 - 4 is characterised by a belt of tall shrub and woodland generally no wider than 5 metres on either side of the stream channel. The substrate in the upper reaches of the stream is one of large boulders and rocks, with very few pools and riffles. There is however one relatively flat area of stream course across the Study Area from the SWS 4 that rises on the north flank of Nei Lak Shan. This site was included in the Stream Survey. After crossing the plateau, the middle reaches of these three feeder streams revert to predominantly rocky and boulder substrate as they pass through dense tall shrub and wooded habitat that has become well established in deeper soil. The SWS (between Tower 6 and 7) was investigated indicated that Pholidota chinensis, Spathoglottis pubescens, Enkianthus quinqueflorus and Camellia euryoids downstream (approximately 20 to 50m from the existing trail and from the proposed alignment).
The source of the San Tau Stream (STS) is characterised by grassland habitat, with only occasional pockets of short shrub growing around boulder outcrops. The uppermost part of the stream at around 550m elevation appears to be only seasonal (flow was observed after rains, but had ceased after a few days without rainfall), with perennial flow only developing further downstream at around 500m elevation. The bed of the upper part of this Stream is characterised by a narrow, hardened earth channel with very little debris. The stream habitat near the proposed Tower 5 location did not reveal any rare or protected flora species.
A cascade of exposed bedrock boulders some 30m high around the 300m elevation level distinguishes the mid-reaches of the San Tau Stream. Here the number of feeder streams increases significantly as the main Stream moves out of generally low shrub/ grassland habitat and abruptly into densely vegetated tall shrub and woodland habitat. The wooded habitat covers the steep sides of the middle San Tau Valley, with notable native broadleaved woodland on the eastern slopes and a large stand of native Chinese Red Pine Pinus massoniana woodland on the west.
Two seasonal streams near Tower 3 were surveyed Pylon 3 Stream (P3S) to the northeast and a stream draining near Ngau Au (NAS) to the southeast. As with the SWS 2-4 and STS, the water qualities in these two streams are anticipated to be high.
A stream at Ngong Ping is located at the proposed Ngong Ping Terminal location (approximately 30m at the terminal location). The stream varies in quality, for example the stream supports Rommer’s Tree Frogs in the SSSI upstream and also has a poor water quality (evidence by visible hydrocarbon sheen in December 2002) and evidence of the discharge of wastes from the Ngong Ping village. The area of stream at the terminal location is considered to be of a lower value because of this contamination. Table 7.12 evaluates stream habitat within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum.
Table 7.12 Evaluation of Streams within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum
|
Criteria |
Remarks |
|
Naturalness |
The watercourses are natural and are dominated by native species. |
|
Size |
The natural watercourses vary in length but some are very long draining large areas of the Lantau hills. |
|
Diversity |
Species diversity is high. |
|
Rarity |
Natural watercourses with clear water are very restricted in the whole of the SAR. |
|
Re-creatability |
Natural watercourses are not easily re-created. |
|
Fragmentation |
These watercourses are linear and continuous; they flow from mountain to sea. |
|
Ecological linkage |
These natural watercourses are of high ecological value for foraging or dispersal for animals of other habitats. |
|
Potential value |
High. |
|
Nursery/ breeding ground |
The natural watercourses provide important breeding grounds for amphibians, fish and invertebrates particularly at Ngong Ping, Sham Wat Stream where species of conservation interest have been recorded. |
|
Age |
Mature. |
|
Abundance/ richness of wildlife |
High for a variety of different taxa including plants, invertebrates, amphibians, reptiles and fish. |
|
Summary |
The natural watercourses within the Study Area are generally evaluated as of high ecological value. They support a wide diversity of species and are species rich. The stream at Ngong Ping is are as having a moderate value due to human disturbance (i.e. through Ngong Ping and stream adjacent to the terminal location). |
According to the investigations of Tam and Wong (1997) the San Tau mangal has the highest species richness of mangrove/ mangrove associate species in the HKSAR, whilst the Tung Chung mangal also ranks highly. Refer to Figure 7.3 (Habitat Map) and Figure 7.4, which presents an image of habitat types within the Study Area.
The mangal at San Tau has been well studied in recent years and therefore is a good database as to the flora and fauna community. This stand is dominated by the mangroves Aegiceras corniculatum, Kandelia candel and the restricted Bruguiera gymnorrhiza. The mangroves Avecinnia marina and Acanthus ilicifolius are well represented, and the restricted mangrove Lumnitzera racemosa is also present. The backshore of the mangal includes Excoecaria agallocha and the restricted mangrove associate Thespesia populnea. The true mangrove community at the Tung Chung mangal is similar, with the exception being the absence of L. racemosa.
On the mudflat beside the San Tau mangal are colonies of the rare seagrasses Halophila ovata and Zostera japonica. The seaweeds Enteromorpha sp. and Colpomenia sinuosa are also seasonally abundant on the mudflat near the seagrass beds. The epifauna and infauna communities are dominated by gastropods of the genera Batillaria, Littoraria, Cerithidea and Nerita, although (closely associated with the seagrass beds) the mudflat is also an important habitat for the horseshoe crabs Tachypleus tridentatus and Carcinoscorpius rotundicauda. The mudskipper Periophthalmus cantonensis is widespread.
Table 7.13 evaluates mangrove and mudflat habitat within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum.
Table 7.13 Evaluation of Mangrove Habitats within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum
|
Criteria |
Remarks |
|
Naturalness |
The mangrove and mudflat habitats are natural and are dominated by native species. |
|
Size |
The mangrove and mudflat habitats habitat within the Study Area is about 20.5 hectares and is moderately sized. |
|
Diversity |
Species diversity is high. |
|
Rarity |
Mangroves are extremely restricted on Lantau and in the SAR. |
|
Re-creatability |
Mangrove plant species can be replanted but to recreate the overall habitat for all flora and fauna is difficult and takes a long time. |
|
Fragmentation |
The mangroves are in a continuous band. |
|
Ecological linkage |
These mangroves are of high value for foraging or dispersal for animals of other habitats. |
|
Potential value |
High value already achieved. |
|
Nursery/ breeding ground |
Very high and important. |
|
Age |
Mature but under stress from airport related projects. |
|
Abundance/ richness of wildlife |
High. |
|
Summary |
The mangrove and mudflat habitat within the Study Area are evaluated as of high ecological value. They support a number of rare/ and or protected plant species and species richness and diversity is high. |
Tung Chung Bay is the largest on North Lantau, with middle reaches around 4m deep.
The outer Bay and the sea channel between the Chek Lap Kok and North Lantau mainland has been partly dredged to meet navigation requirements and to maintain water quality in Tung Chung Bay. The Bay’s estuarine waters link the coastal marine environment and the freshwater habitats of San Tau Stream and Tung Chung Stream. Due to the variable physio-chemical environment brought about by changing salinity in the Bay, the coastal waters support a wide diversity of fish species. The most abundant species include Flathead Mullet Mugil cephalus and Tiger Fish Therapon jaruba. Refer to Figure 7.3 (Habitat Map) and Figure 7.4 which presents an image of habitat types within the Study Area.
Table 7.14 evaluates coastal water habitat within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum.
Table 7.14 Evaluation of Coastal Water Habitats within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum
|
Criteria |
Remarks |
|
Naturalness |
The coastal waters are natural but impacted upon by the construction and operation of the international airport. |
|
Size |
The coastal water within the Study Area is about 110 hectares. |
|
Diversity |
Species diversity is high. |
|
Rarity |
Coastal water are widespread on Lantau and in the SAR |
|
Re-creatability |
Coastal water habitats cannot easily be re-created. |
|
Fragmentation |
Coastal waters are continuous. |
|
Ecological linkage |
Linkage for marine species. |
|
Potential value |
Moderate to high value already achieved. |
|
Nursery/ breeding ground |
High and important. |
|
Age |
Mature but under stress from airport related projects. |
|
Abundance/ richness of wildlife |
High. |
|
Summary |
The coastal habitats within the Study Area are evaluated as of high ecological value. |
The ‘Developed Area’ refers to buildings and structures, hard-surfaced paths and road/ drainage infrastructure that can be found at Ngong Ping, Chek Lap Kok (by the proposed Tower 2 location), at Tung Chung (around the proposed Tower 1 location) and at the proposed site of the Tung Chung Cable Car Terminal that is currently occupied by the Tung Chung bus terminus. There is flora in these areas, but only in the form of roadside planting and various ruderal species. Refer to Figure 7.3 (Habitat Map) and Figure 7.4 which presents an image of habitat types within the Study Area
Table 7.15 evaluates developed areas within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum.
Table 7.15 Evaluation of Developed Areas within the Study Area using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum
|
Criteria |
Remarks |
|
Naturalness |
The developed areas are not natural. |
|
Size |
The developed areas are relatively small. |
|
Diversity |
Species diversity is extremely low. |
|
Rarity |
Developed areas are not restricted in the SAR. |
|
Re-creatability |
Easily recreated. |
|
Fragmentation |
N/A. |
|
Ecological linkage |
These developed areas are of extremely low value for foraging or dispersal for animals of other habitats. |
|
Potential value |
Very low value already achieved. |
|
Nursery/ breeding ground |
Very low. |
|
Age |
N/A. |
|
Abundance/ richness of wildlife |
Practically no species present. |
|
Summary |
Developed areas within the Study Area are evaluated as of very low ecological value (for obvious reasons). . |
A study into the distribution of small mammals at Chek Lap Kok undertaken by Chandrasekar-rao (1994) revealed a number of rodents, including Rattus sikkimensis, Rattus rattus flavipectus, Rattus norvegicus and Bandicota indica. Despite the airport works, it is feasible that these species are still present at Chek Lap Kok and are likely to be present in other parts of the Study Area. This is borne out by recent records of Rattus sikkimensis at Ngong Ping (Ove Arup and Partners, 2002).
Other small mammals records at Ngong Ping include the Chestnut Spiny Rat Niviventer fulvescens and the restricted Ryukus mouse Mus caroli (ibid.). Anecdotal records of small mammals near the Study Area reported in include N. fulvescens in plantation woodland at Pak Kung Au (Porcupine! 21, 2000), indicating wide species distribution.
Of the larger mammals specifically noted as occurring on Lantau Island by Hill and Phillipps (1981), only barking deer Muntiacus reevesi, wild boar Sus scrofa and seven-banded civet Viverricula indica were reported. A more recent account on ‘sightings’ of the larger mammals throughout Hong Kong by Reels (1996) revealed that only the barking deer had been directly observed on Lantau from all sightings between mid-1992 and late 1996. An adult barking deer (approximately 65cm in height to the shoulder) was encountered during a field survey 12th December 2002. As reported in Porcupine! (22; 2001), the first confirmed sighting of the Ferret-badger Melogale moschata on Lantau was between Tung Chung Au and Lantau Peak, not far from the Study Area; and the second record of M. moschata and another of M. reevesi were also made around Tung Chung Au.
A total of four confirmed and one likely ground mammal species were recorded in the Study Area during the survey. No bats were recorded during the survey. Annex F – Part C shows the Mammal and Herpetofauna Survey Data.
One visual/ aural observation of the Barking Deer Muntiacus reevsii was made outside the Study Area on 19th May 2002 in tall coastal shrub/ woodland off the coastal path near Hau Hok Wan. Two further aural records of M. reevsii were made within the Study Area in early October: one from the wooded western side of the San Tau Valley and another in woodland at the back of the Ngau Au (Figure 7.2refers).
The Barking Deer M. reevsii is a medium sized herbivorous mammal that tends to browse and graze, but also feeds on fruit (Hill and Phillips, 1981 In BMT, 2002). The deer generally favours densely vegetated areas where there is no human disturbance, such as the tall shrub and woodland habitat where the survey observations were made. The woodland and tall shrub habitats particularly those present within the gullies and valleys provide adequate vegetation cover to sustain populations of M. reevsii.
Mammal scats were found on more than one occasion on the upland footpath along the western ridge of the San Tau Valley. The habitat type was tall grass at the edge of low dense shrub at an elevation of around 400m. From examination of the scats, and cognisance of the habitat type, it is considered that the scats are likely from a Ferret Badger Melogale moschata or possibly a civet. Both of these species include amongst their diet various insects and rodents that are present in the vicinity.
Records of small mammals within the Study Area include the jawbone of a small rodent that was found amongst bird droppings near a boulder outcrop beside the proposed Angle Station in May. It is considered that the bone is from Rattus sikkimensis. Upon examination of the droppings, they were almost certainly from an Owl that would seem to use the boulder outcrops in this area as a feeding station, having caught its prey in the surrounding open grassland habitat.
Other rodent observations were made in July and August 2002 of the Rattus flavipectus at the back of the Tung Chung mangal, near cultivated/ developed land; whilst several burrows of the species were present in adjacent bunds at the backshore and in adjacent abandoned cultivated land. The common rat Rattus norvegicus were observed around San Tau village during the course of the survey.
Of note was the absence of Feral Cattle (or any signs of) within the upper part of the Study Area out of Ngong Ping.
Given the area of suitable feeding habitat for raptors in general, as well as various records of raptors above this habitat type from the Bird Survey, rodents are likely to be widespread throughout the upland grassland habitat.
Past records of amphibians and reptiles in the Study Area focus on surveyed habitat at Ngong Ping, San Tau and Tung Chung. There are also records for the broader environs of the Tung Chung Valley to the east and Keung Shan to the west.
Consolidated records from Lau and Dudgeon (1999) in BMT (2002) show the presence of a number of amphibians within and around the Study Area. Table 7.16 summarises these species and their locations.
Table 7.16 Historical Amphibian Records in the Study Area (Lau and Dudgeon, 1999)
|
Species |
Common Name |
Location |
Habitat |
|
Bufo melanostictus |
Asian Common Toad |
NP ST TC |
PW F F |
|
Kaloula pulchra |
Asiatic Painted Frog |
NP |
PW |
|
Leptolalax pelodytoides |
Leaf-litter Toad |
NP |
S |
|
Megophrys branchykolos |
Short-legged Toad |
NP |
S |
|
Microhyla ornata |
Ornate Pigmy Frog NP |
NP TC |
S F |
|
Microhyla pulchra |
Marbled Pigmy Frog |
NP TC |
F F |
|
Polypedates megacephalus |
Brown Tree Frog |
NP TC |
P F |
|
Rana exilispinosa |
Lesser Spiny Frog |
NP |
S |
|
Rana guentheri |
Gunther’s Frog |
NP TC |
S/ M F |
|
Rana limnocharis |
Paddy Frog |
NP TC |
P F |
|
Rana livida |
Green Cascade Frog |
NP |
S |
|
Rana macrodactyla |
Three-striped Grass Frog |
TC |
F |
|
Rana ruglosa |
Chinese Bullfrog |
TC |
F |
Notes:
Location: NP = Ngong Ping; ST = San Tau; TC = Tung Chung
Habitat: (S) =Stream; (PW) = Plantation Woodland; (M) = Marsh; (P) = Pool; (F) = Field
Source: Adapted from BMT (2002)
During surveys by Ove Arup and Partners (2002) a number of tadpoles of Romer’s Tree Frog Philautus romeri were found in seasonal streams at the stream of Ngong Ping in the SSSI, however these locations (or stream sections) are not in close vicinity (i.e. within 500m) of the Ngong Ping Terminal site. In terms of habitat type, P. romeri generally prefers low shrub and grass in well-vegetated flat areas where it predates on spiders and small insects such as termites and crickets (Karsen et al, 1998). The preferred habitat is commonly near a stream course or another source of water that is convenient for breeding (as noted by Lynch). Given its small size and predation pressure faced by larger amphibians, this species is of limited mobility and so is very sensitive to habitat fragmentation. Romer’s Tree Frogs are mostly found within the plantation woodland and tall shrub habitat in the Ngong Ping SSSI (Ove Arup and Partners, 2002). This species is protected under the Wild Animals Protection Ordinance, Cap. 170. The same survey also recorded the restricted Megophrys branchykolos, possibly another endemic species.
The locally uncommon Three-striped Grass Frog Rana macrodactyla was found along the grassy banks of Sham Wat Stream (with headwaters flowing through the Study Area) during an ecological survey (Chan and Lau, 2001).
Table 7.17 summarises details from various sources in Ove Arup and Partners (2002) of reptile records made around Ngong Ping. Amongst these, the terrapin Chinemys reevesii, found in seasonal streams at Ngong Ping, is listed as “endangered” in the IUCN Red List. Of the snakes, Achalinus rufescens is rare; Amphiesma stolatum and Oligodon cinereus are uncommon/ restricted; and Elaphe radiata is listed as “endangered” in the China Red Data Book (Zhao, 1998 in Ove Arup and Partners, 2002).
Table 7.17 Historical Reptile Records from Ngong Ping (OAP, 2002) and Green Lantau Conservation Stategy
|
Species |
Common Name |
Habitat |
|
Achalinus rufescens Rufous |
Burrowing Snake |
Plantation/ woodland/ shrubland |
|
Amphiesma stolatum |
Buff-striped Keelback |
Stream |
|
Calotes versicolor |
Changeable Lizard |
Shrubland/ plantation |
|
Chinemys reevesii |
Reeves’ Terrapin |
Stream |
|
Cyclophiops major |
Greater Green Snake |
Shrubland |
|
Elaphe prophyracea* |
Mountain Racer |
- |
|
Elaphe radiata |
Copperhead Racer |
Grassland |
|
Eumeces quadrilineatus |
Blue-tailed Skink |
Shrubland |
|
Gekko chinensis |
Chinese Gecko |
Woodland/ plantation |
|
Hemidactylus bowringii |
Bowring’s Gecko |
Village |
|
Lycodon ruhstrai* |
Mountain Wolf Snake |
- |
|
Mabuya longicaudata |
Long-tailed Skink |
Shrubland |
|
Naja atra |
Chinese Cobra |
Shrubland |
|
Oligodon cinereus |
Golden Kukri Snake |
Grassland |
|
Oligodon formosanus |
Taiwan Kukri Snake |
Plantation |
|
Opisthotrpos kuatunesis* |
Striped Stream Snake |
- |
|
Ptyas korros |
Indo-Chinese Rat Snake |
Woodland |
|
Rhabdophis subminiatus |
Red-necked Keelback |
Shrubland/ woodland |
|
Scincella reevesii |
Reeve’s Smooth Skink |
Shrubland |
|
Trimeresurus albolabris |
Bamboo Snake |
Shrubland/ plantation |
|
Trimeresurus monticola* |
Mountain Pit Viper |
- |
|
Tropidophorus sinicus |
Chinese Waterside Skink |
Stream |
|
Xenochrophis piscator |
Checkered Keelback |
Agriculture |
Source: Adapted from BMT (2002)
*Source: Lau M.W.N (Unknown) University of Hong Kong: Herpetologist and ecologist In A Green Lantau Conservation Strategy
Other reptile observations in the broader Tung Chung Valley area, and particularly around Tung Chung Road, as presented in Porcupine! that are not presented in Table 7.14include the Large-spotted Cat Snake Boiga multimaculata and King Cobra Ophiophagus hannah (Porcupine! 23, 2001). Given the similarity in habitat type and the ecological linkage, it is likely that these two species are also present within the Study Area.
To the west of the Study Area, an unidentified genus of snake was identified at Keung Shan in July 1999 (Kolby and Lazell, 2001). Hill streams flow westerly from the main plateau out of Ngong Ping towards this general area (Sham Wat Road), and hence the hill streams provide ecological linkage between the Study Area and the general locale at which the snake was encountered. A previous observation at Keung Shan (some way out of the Study Area, but representative of habitat within) was of the restricted Dark forest skink Scincella modesta (Porcupine!15, 1996).
Despite the assertion by Dudgeon and Lau (1999) that destruction of all natural habitats at Chek Lap Kok for the international airport precluded in situ protection of Romer’s Tree Frog Philautus romeri, a single specimen was caught at the abandoned village on the north side of the former island in July 2000 (Lynch, 2001). It was considered by Lynch that, given the presence of various suitable containers scattered around that could hold water for breeding and the absence of physical disturbance in the immediate surroundings, a small population of P. romeri could remain in this area. It should be noted that the village location is at the opposite end of Chek Lap Kok to the proposed site of the Angle Station.
A total of 8 amphibians and 8 reptiles (5 snakes and 3 lizards) were recorded in the Study Area from field survey. Table 7.18summarises the species observed, their location and habitat type, abundance and status (according to Karsen et al, 1998). Annex F – Part C shows the Mammal and Herpetofauna Survey Data.
Table 7.18 Reptile and Amphibian Survey Data for the Study Area (2002)
|
Species |
Common Name |
Location and Habitat |
Abundance |
Status |
|
Amphibians |
|
|
|
|
|
Bufo melanostictus |
Asian Common Toad |
Abandoned cultivation at proposed Ngong Ping Terminal |
C |
C and W |
|
Leptolalax pelogytoides |
Leaf Litter Toad |
Concrete culvert near SWS 4. |
C |
FC & W |
|
Megophrys branchykolos |
Short-legged Toad |
Slow mid-course of SWS 4 |
A |
FC and W |
|
Microhyla ornata |
Ornate Pigmy Frog |
Abandoned cultivation at proposed Ngong Ping Terminal |
A |
C and W |
|
Polypedates megacephalus |
Brown Tree Frog |
Abandoned cultivation at Tung Chung (Ngau Au) and lower STS |
B |
C and W |
|
Rana livida |
Cascade Frog |
Lower mid-course of SWS 3 |
B |
C and L |
|
Rana macrodactyla |
Three-striped Grass Frog |
Abandoned cultivation at Tung Chung (Ngau Au) |
B |
C and W |
|
Rana ruglosa |
Chinese Bullfrog |
Abandoned cultivation at proposed Ngong Ping Terminal |
B |
C and L |
|
Reptiles |
|
|
|
|
|
Amphiesma stolatum |
Buff-striped Keelback |
Abandoned cultivation at Tung Chung (Ngau Au) |
A |
C and L |
|
Calotes versicolour |
Changeable Lizard |
Low Shrub (various locations) |
C |
VC and W |
|
Eumeces quadrilineatus |
Blue-tailed Skink |
Low shrub/ boulder habitat at northern Ngong Ping plateau |
A |
C and L |
|
Elaphe radiata |
Copperhead Racer |
Footpath near San Tau, by Tall Shrub Habitat. |
|
|
|
Mabuya longicaudata |
Long-tailed Skink |
Village (Developed Area) at San Tau and Chek Lap Kok plantation |
B |
L |
|
Naja atra |
Chinese Cobra |
Grassland/ low shrub near Ngong Ping |
A |
C and W |
|
Ophiophagus hannah |
King Cobra |
Grassland by Angle Station |
A |
U and L |
|
Pytas sp. |
Rat snake |
Coastal shrub at Sha Lo Wan* |
A |
C and W |
Note: *Observed outside Study Area
Abundance: A = 1 individual; B = 2-5 individuals; C = 5-10 individuals
Status: U = Uncommon; FC = Fairly Common; C = Common; VC = Very Common; W = Widespread;
L = Localized
Source: Adapted from BMT (2002)
All species presented in Table 7.18 are common, with the exception of the fairly common Short-legged Toad Megophrys branchykolos that was found in a slow flowing section of Shan Wat Stream (SWS) feeder stream 4, and the uncommon and localised King Cobra Ophiophagus hannah of which a sloughed adult skin was recovered from by a rocky outcrop in grassland habitat at the foot of the Angle Station (Figure 7.2 refers).
In general, M. branchykolos inhabits hill streams that have well vegetated banks where they feed on earthworms, termites, woodlice and young crickets (Karsen et al, 1998). This Toad can reportedly be seen perched on streamside boulders, but rarely seen in the open (ibid.). Given the relative homogeneity in character between the observation location of SWS 4 and SWS’s 2 and 3, it is possible that this species is also present at these other locations despite not being recorded during the survey.
The toad L. pelodytoides is closely related to M. branchykolos (Family Pelobitidae) and frequents similar. Given the 30m distance between the culvert in which this specimen was found and SWS 4, it is feasible that this toad also inhabits the nearby stream. However, no specimens were observed in any of the streams during the survey.
Despite a review of published literature the natural diet of L. pelodytoides is unknown, although potential food sources in the culvert in which the specimen was observed included diptera larvae and fish (i.e. possible fish-egg predation). The first HKSAR record for this species was from a hill stream in the Ngong Pong area (Lau and Dudgeon, 1999).
The King Cobra Ophiophagus hannah can be found in a wide variety of habitats, including grassland, shrub habitat, woodland and occasionally cultivation where it feeds upon other snakes and lizards (ibid.). A sloughed skin was recovered from grassland, however the species may possibly be found throughout the Study Area.
A localised Green Cascade Frog Rana livida was observed at a rocky stream course at the west of the Ngong Ping plateau in SWS 3.
From the night time survey at Chek Lap Kok the village area referred to by Lynch (2001) was investigated and no evidence of Romer’s Tree Frog Philautus romeri was found. The only species that was recorded from this visit was a single Long-tailed Skink Mabuya longicaudata at the proposed Angle Station site.
The general area around the Study Area is known to be of high conservation importance for Hong Kong’s two Birdwing butterflies: the uncommon Troides helena – a locally protected species – and the rare Golden Birdwing Troides aeacus. In September 1997 five T. helena were observed at Ngong Ping, en route to Tei Tong Shan to the east of the Study Area (Young, 1998; Young and Reels, 1998). A few Common Rose butterfly Pachliopta aristolochiae were also seen flying in the vicinity (ibid). The larval food plant of P. aristolochiae, the vine Aristolochia fordiana, was spotted alongside the footpath, but not the normal food plant of Troides helena, namely Aristolochia tagala.
In April and June 1998, Troides helena was recorded in woodland and the riparian zone of Wong Lung Hang Stream (Mott Connell, 2000). This would suggest that this species covers a wide range in the Tung Chung area.
Records from the Hong Kong Lepidopterists’ Society (HKLS) include ‘several’ Troides aeacus on the path from Ngong Ping to Tung Chung (outside the Study Area) in September 1999 (Wong, 1999) and in September 2000 (Wong, 2000). During the 1999 visit it was noted that Zanthoxylum nitidium flowering along the path attracted the species. Also recorded during the September 2000 visit were a few very rare Ypthima motschulskyi (ibid.). A third trip to the general area was made by the HKLS in October 2001 – this time to San Tau were ‘several’ rare White Dragontail Lamproptera curius were recorded by the lower stream (Lai, 2001).
From the Mott Connell (2000) study it is reported that, combined with previous records made by Bascombe (1993), the butterfly total in the ‘Tung Chung’ area was 60 species. The exact locations of Bascombe’s observations (49 species) are unknown, but based on experience elsewhere in the SAR most observations were probably made in wooded habitats and agricultural lands. The species list is presented in Annex F – Part D. Of these species, three were considered rare (Forget-Me-Not Catochrysops strabo, Painted Jezebel Delias hyparete and Lesser Band Dart Potanthus trachala) and two very rare (Brownie Miletus chinensis and Straight Pierrot Castalius rosimon).
The general environs of the Tung Chung area are also of some note for Odonata. The uncommon dragonfly Gynacantha japonica was observed at Ngong Ping in September 1997 (Young and Reels, 1998); whilst more recently the uncommon Diplacodes nebulosa was also recorded along the banks of lower Sham Wat Stream that flows across the plateau through the Study Area (Chan and Lau, 2001). Three endemics have also been recorded from hill streams at Sunset Peak: Rhipidolestes janetae, Sinostica ogatai, and Drepanostica hongkongensis (Wilson, 1997). Both S. ogatai and D. hongkongensis were observed at Tei Tong Tsai (east of Po Lin and outside the Study Area) in May 2002.
The Mott Connell (2000) surveys recorded 19 dragonfly species around Tung Chung. All species are common and widespread with the exception of the fairly common Neurobasis chinensis.
The survey has identified a total of 46 species of butterfly and 11 species of dragonfly within the Study Area. Table 7.19below summarises the number of butterflies found in each of the habitats surveyed.
Table 7.19 Butterfly Survey Data for the Study Area (2002)
|
Location |
Species Richness |
|
Grassland/ low shrub |
24 |
|
Tall shrub |
23 |
|
Woodland |
20 |
|
Cultivation |
15 |
|
Abandoned cultivation |
18 |
|
Mangrove |
7 |
|
Total |
46 |
Source: Adapted from BMT (2002)
Note: No butterfly observations were recorded in marsh and plantation habitats/ locations.
In terms of species richness, ‘grassland/ low shrub’, ‘tall shrub’ and ‘woodland’ are very similar, as is species diversity in the latter two habitat types. This would indicate that these three habitats within the Study Area are of similar importance. There is great similarity in the habitat value for butterflies offered by abandoned and active cultivation.
Combined with previous butterfly records of Bascombe (1993) cited in Mott Connell (2000), and the survey records of Year (2000 survey), a total of 73 butterfly species has been recorded within or in proximity to the Study Area. The species list from survey work under this study is presented as Annex F – Part E.
Notable species recorded during this Survey include a single uncommon Birdwing Troides helena near cultivated land at San Tau and the rare Dragontail Lamproptera curius at the back of the mangrove habitat near the confluence of San Tau Stream with Tung Chung Bay (Figure 7.2refers).
All four species of Hesperiidae recorded were also uncommon, as were the following Nymphalidae species: White-edged Blue Baron Euthalia phemius, Yellow Pansy Junonia hierta and White Commodore Parasarpa dudu. One species of the Pieridae, Yellow Orange Tip Ixias pyrene, is also uncommon.
With reference to Lau (1997), Bascombe et al. (1999) and others, records of synergies for larval food plants and adult nectar source(s) for those butterflies of conservation at proposed cable car structure locations have been reviewed (Annex F – Part Frefers). The only relationship of note is that between the White Commodore Parasarpa dudu and two of its adult food plants – Rhaphiolepsis indica and Zanthoxylum avicennae. These two shrub species were present in the vegetation community at the proposed site of Tower 4, whilst R. indica was also recorded at Tower 3. Two specimens of the butterfly P.dudu were noted in similar habitat within the Study Area.
The odonate community along the alignment was rather less diverse than that of the butterflies. Table 7.20below summarises the odonate records for the Study Area.
Table 7.20 Odonate Survey Data for the Study Area (2002)
|
Species |
Location |
Abundance |
Status* |
|
Euphaea decorata |
All sections of SWS 2, 3 and 4 |
D |
C |
|
Rhinocypha perforata |
All sections of SWS 2, 3 and 4 |
D |
C |
|
Coeliccia cyanomelas |
Upstream SWS 4 |
A |
C |
|
Anax immaculifrons |
Upstream SWS 4 pool |
A |
FC |
|
Ischnura senegalensis |
Upstream SWS 4 pool |
B |
A |
|
Orthetrum glaucum |
All SWS and Upstream STS |
D |
A |
|
Orthetrum pruinosum |
Middle SWS 1 |
B |
A |
|
Pantala flavescens |
Upstream SWS 3 and 4 |
D |
A |
|
Trithemis festiva |
All sections of SWS 2, 3 and 4 |
D |
A |
|
Trithemis aurora |
Upstream SWS 3 and 4 |
D |
A |
|
Stylogomphus chunliuae |
Upstream SWS 4 |
A |
UC |
Note: * Status according to Wilson, 1997.
Abundance: A = 1 individual; B = 2-5 individuals; C = 5-10 individuals
Status: FC = Fairly Common; UC = Uncommon, C = Common; A = Abundant
Source: Adapted from BMT (2002)
Only the dragonfly Stylogomphus chunliuae is uncommon. A single specimen was recorded over grassland next to Sham Wat Stream 4 (Figure 7.2 refers). This species would likely be restricted to similarly vegetated areas by streams within the Study Area.
All other odonate records were of common or ‘abundant’ (i.e. very common) species, with the exception of the fairly common Anax immaculifrons – also noted at the same location as S. chunliuae.
Records of bird activity in the vicinity of the upland section of the Study Area are limited, as access through the area is difficult. However, there are records for the broader Tung Chung valley area, including a number of rare species: Bonelli's Eagle Hieraaetus fasciatus; Crested Goshawk Accipiter trivirgatus; Grey Bushchat Saxicola ferrea; Japanese Quail Coturnix japonica; and Chestnut Bulbul Hemixos castanonotus (HKBWS pers. comm.). Uncommon species from the same source include: Lesser Coucal Centropus bengalensis; Buzzard Buteo buteo; Pallas's Warbler Phylloscopus proregulus; White-backed Munia Lonchura striata; Hwamei Garrulax canorus; and Asian Brown Flycatcher Muscicapa dauurica.
Notable records from Ngong Ping cited in Ove Arup and Partners (2002) include the Brown Thrush Turdus chrysolaus, Mountain Bush Warbler Cettia fortipes, Mugimaki Flycatcher Ficedula mugimaki, and Tristam’s Bunting Emberiza tristrami. All these species are rare or uncommon migrants that can be found in tall shrub, woodland and/ or plantation (Viney et al, 1994). The bird survey undertaken by Ove Arup and Partners (2002) also recorded two rare species: the Chestnut Bulbul Hemixos castanonotus in plantation and woodland and White’s Thrush Zoothera dauma in woodland. The precise location of these observations is unknown, although as wooded habitat is present throughout the general surroundings there is potential for activity by these species within the Study Area.
A total of 72 species have been recorded from the Study Area from the baseline surveys. Table 7.21below summarises the species richness and diversity of each of the key habitat types within the Study Area. The full data set is presented in Annex F – Part G.
Table 7.21 Bird Survey Data for the Study Area (2002)
|
Habitat Type |
Species Richness |
|
|
Grassland |
9 |
|
|
Low shrub |
13 |
|
|
Tall shrub |
26 |
|
|
Woodland |
30 |
|
|
Abandoned cultivation |
31 |
|
|
Mudflat/ mangrove |
27 |
|
|
Total Species* |
72 |
|
Note: some species were recorded in more than one habitat type
due to the bird survey baseline data which used difference habitat classifications, marsh, plantation and
cultivation habitat are incorporated into the habitat types presented in the Table (i.e. marsh with grassland,
cultivation with abandoned cultivation and plantation with tall shrubland).
Source: Adapted from BMT (2002)
In terms of relative habitat value for birds within the Study Area, the woodland and tall shrub habitat that dominates the mid slopes of the Study Area offers the significant species richness and diversity along with abandoned cultivation and mudflat/ mangrove. This is a product of a number of factors such as overall area and ecological linkage, lack of human disturbance, likely vegetation diversity and the presence of numerous shrubs and trees that offer shelter and feeding opportunities.
Woodland habitat is of high conservation value for bird species, with a number of bird species recorded being either rare or uncommon (refer to Annex F – Part G). Of the rare species in woodland, only the Crested Serpent Eagle Spilornis cheela and the Chestnut Bulbul Hypsipetas castananonotus are resident – the other species all being migrants or winter visitors. In addition, rare species recorded in tall shrub habitat were raptors observed overhead, and for which woodland may be an important habitat (possibly as a roost, and likely as a perch).
The similar character of grassland and low shrub is evident from the similarly of the data in Table 7.21. One record of particular note in grassland was the rare Upland Pipit Anthus sylvana.
The birds thus far recorded in the abandoned cultivation habitat near Ngong Ping terminal, are generally common and widespread species that are typical in disturbed areas with a human presence and a partly built environment. However, rare raptors have been observed over the abandoned cultivation near Tung Chung (southeast of Tower 3).
The coastal mudflat and mangrove habitats of Tung Chung Bay support quite a diverse range of birds, with over 40 Little Egret Egretta garzetta recorded between October and December 2002. Although a fairly common species locally, the HKSAR (particularly the north west New Territories) is a global stronghold for E. garzetta. Also of note were the uncommon/ localised Reef Egret Egretta sacra and a solitary Night Heron Nycticorac nucticorax.
Table 7.22summarises the observations of note made during the Survey from May to January 2002.
Table 7.22 Uncommon and Rare Bird Records in the Study Area (2002)
|
Species |
Common Name |
Habitat Observed |
|
Accipiter gularis |
Japanese Sparrow Hawk |
Abandoned cultivation (overhead) |
|
Accipiter trivirgatus |
Crested Goshawk |
Tall shrub |
|
Accipiter virgatus |
Besra |
Tall shrub (overhead) |
|
Anthus sylvana |
Upland Pipit |
Grassland |
|
Bubo bubo |
Eagle Owl |
Woodland |
|
Centropus bengalensis |
Lesser Coucal |
Grassland |
|
Cettia fortipes |
Brownish-flanked Bush Warbler |
Woodland |
|
Coccothraustes coccothraustes |
Chinese Grosbeak |
Woodland |
|
Falco tinnunculus |
Kestrel |
Abandoned Cultivation (overhead) Grassland |
|
Ficedula albicilla |
Red-throated Flycatcher |
Woodland |
|
Garrulax canorus |
Hwamei |
Low shrub Tall shrub |
|
Haliaeetus leucogaster |
White-bellied Sea Eagle |
Grassland (overhead) |
|
Hieraaetus fasciatus |
Bonelli’s Eagle |
Abandoned cultivation (overhead) |
|
Muscicapa latirostris |
Brown Flycatcher |
Woodland |
|
Phylloscopus fuscatus |
Dusky Warbler |
Abandoned cultivation Tall shrub Mangrove |
|
Phylloscopus reguloides |
Blyth’s Leaf Warbler |
Abandoned cultivation Woodland |
|
Phylloscopus tenellipes |
Pale-legged Leaf Warbler |
Abandoned cultivation Woodland |
|
Spilornis cheela |
Crested Serpent Eagle |
Woodland (overhead) |
|
Turdus cardis |
Japanese thrush |
Woodland |
|
Urosphena squameiceps |
Asian Subtail Warbler |
Woodland |
|
Zoothera citrina |
Orange-headed Thrush |
Tall shrub |
Note: ^ Observation of the Eagle Owl was incidental and outside the routine Bird Surveys.
Source: Adapted from BMT (2002)
Species that favour wooded habitat typical of the lower plateau and lowland part of the Study Area include a range of rare migrants and visiting passerines including thrushes, warblers, finches, flycatchers and bulbuls. Other uncommon/ localised winter visitors that are typical of densely vegetation habitats such as abandoned cultivation, tall shrub and woodland include the Brown Flycatcher Muscicapa latirostris and Dusky Warbler Phylloscopus fuscatus.
On top of the plateau in an upland environment where the more open grassland and low shrub habitat is prevalent, the rare Upland Pipit Anthus sylvana was recorded. Other typically upland species include the Lesser Coucal Centropus bengalensis and Hwamei Garrulax canorus – both common species that favours the dense cover provided by tall shrub and woodland habitat, indicating that it may be widespread in the Study Area.
The birds thus far recorded in the abandoned cultivation habitat at Ngong Ping, near the proposed Ngong Ping Terminal, are generally common and widespread species that are typical in disturbed areas with a human presence and a partly built environment. Of particular note is the rare Pale-legged Leaf Warbler Phylloscopus tenellipes.
Bonelli’s Eagle Hieraaetus fasciatus, Besra Accipiter virgatus, Crested Goshawk A. trivirgatus and Japanese Sparrow Hawk A. gularis all prefer nesting in dense vegetation, usually in tall shrub and woodland, but would likely cover all habitats within the Study Area in search of prey. The Kestrel Falco tinnunculus is not uncommon but is of note, as it would feed on small ground prey from aerial hunting across low shrub and grassland habitat.
The observation of the Eagle Owl Bubo bubo in May 2002 was indirect and based on droppings of this species that were found in grassland habitat at the north end of the Ngong Ping plateau near the proposed Nei Lak Shan Angle Station. The droppings contained the jawbone of a small, unidentified rodent species that fell prey to the owl. An incidental direct observation of the Owl was made in June in the stand of Chinese Red Pine on a hillside mid-way down San Tau Stream (Figure 7.2 refers). The bird was perched in the pine stand and flew around the area upon disturbance before returning to its perch. It is possible that the owl has a nest in this area as it is very undisturbed and allows easy access to the plateau where the droppings were found.
Records from undisturbed stream habitat of a similar quality, such as that in Tung Chung Stream, provide a proxy to the potential conservation value of streams within the Study Area.
More than 30 families of macroinvertebrates have been found in the main Tung Chung stream (Maria Salas, pers. comm. 2000; Chan, 1996). Families/ taxa present in Tung Chung stream that appear to be generally uncommon in HKSAR streams (i.e. present in < 25% of streams) are the mayflies (Ephemeroptera) Procloeon venustum and Centroptilum sp., and the beetle (Coleoptera) families Dysticidae and Driopidae.
The lower reaches of Tung Chung stream have been shown by Chong and Dudgeon (1992) to have a diverse fish fauna. Notable records include the locally restricted and rare Acrossocheilus wenchowensis beijiangensis, and the locally restricted and uncommon rice fish, Oryzias curvinotus. The former has only been observed in the lower reaches of both Tung Chung stream and the neighbouring Wong Lung Hang stream to the north (Cheung, 1998 In BMT, 2002).
More directly linked with the Study Area than Tung Chung Stream is Sham Wat Stream. Chan and Lau (2001) report that fish life was both diverse and abundant priorto channelisation and construction work, with a total of 15 fish species recorded. Notable records include a goby previously unrecorded in Hong Kong freshwaters, Redigobius cf. bikolanus; the carp Nicholsicypris normalis, thought to be restricted to the east NT, was abundant; and two rarely seen sleepers, Eleotris acanthopoma and E. melanosoma. It was considered from the species diversity that Sham Wat Stream was a very productive ecosystem.
Recently completed surveys at Ngong Ping by Ove Arup and Partners (2002) recorded only the freshwater crab Somanniathelphusa zanklon from streams thereat. The crab was reportedly abundant. There were no records of freshwater fish from Ngong Ping streams.
The stream survey focused on freshwater stream habitat from which a total of four species of fish and one species of eel within the Study Area, with greatest abundance and species diversity recorded from the lower reaches of San Tau Stream – the largest stream in the Study Area. The summarised data set from the stream surveys is presented in Annex F – Part H.
The Horse-mouth fish Parazacco spilurus is the most common and abundant of the species recorded. The other freshwater fish species were the Flat-headed loach Oreonectes platycephalus; the goby Ctenogobius duospilus (both widespread) and the Vietnam catfish Silurus cochinchinensis that was only found in mid San Tau Stream. A single eel Anguilla sp. was observed in a drainage channel next to agricultural land beside the Tung Chung Mangal.
A number of freshwater crustaceans were also identified during survey, including the crab Nanhaipotamon hongkongense in Sham Wat Steam 4; the Small Long-armed shrimp Macrobrachium hainanense in Sham Wat Steams 3 and 4 and lower San Tau Stream; and the Freshwater shrimp Caridina serrata in San Tau Stream.
Other notable records from the stream survey include larvae and adults of the caddisfly Anisocentropus maculates in the stream to the northeast and southeast of Tower 3 (i.e. P3S and NAS).
Both the freshwater snail Physa acuta and larvae of Chironomus/ Polypedilum spp. Were dominant in SWS 1 – the snail being an indicator of organic pollution and the Dipteria larvae indicators of low oxygen environments.
There is broad background data and information available on the coastal environment of Tung Chung Bay and its environs from a number of academic and consultancy studies.
Almost all of these were in response to development of the international airport at Chek Lap Kok and associated infrastructure, and the parallel development of the Tung Chung New Town.
Although the coastal ecosystems function in an integrated manner, the literature review for the coastal environment has been divided for presentation convenience into:
1. mudflat/ mangrove habitat
2. seagrass/ horseshoe crabs; and
3. shallow sub-tidal habitat.
There are two distinct mangals (mangrove habitats) around Tung Chung Bay: at San Tau and the so-called Tung Chung mangal. These mangals have developed on areas of exposed and shallow sub-tidal sand and mudflat at the south and west of Tung Chung Bay.
The San Tau mangal covers an area of around 2.14ha and, according to the investigations of Tam and Wong (1997), supports 18 of the 20 species of mangrove and associated flora included in the investigations – the highest for any mangal investigated in the HKSAR. The stand at Tung Chung supports 14 of the 20 species, although together these two stands supported 19 species, only the true mangrove Heritiera littoralis was not recorded. It is noted that Tung Chung mangal was ranked joint 4th out of the 43 stands investigated in terms of vegetation community diversity.
The San Tau stand was dominated by Aegiceras corniculatum, Kandelia candel and the restricted Bruguiera gymnorrhiza, with Avecinnia marina, Acanthus ilicifolius and the backshore mangrove Excoecaria agallocha also represented to a lesser extent (ibid.). Backshore vegetation at San Tau includes Zoysia sinica, Suaeda australis, Limonium sinensis and Sesuvium portulacastrum, with mangrove associate species Hibiscus tiliaceus, Pandanus odoratissimus and Caesalpinia crista recorded further landward. The restricted tree Celtis biondii has also been recorded from the far backshore (Zhuang et al., 1997).
There was a similar true mangrove community structure in the Tung Chung mangal, although the restricted true mangrove Lumnitzera racemosa that was present at San Tau was absent from Tung Chung. It is of note that the restricted mangrove associate Thespesia populnea was present at both mangals. The flora list for these mangals is presented in Table 7.23.
The most abundant species in the San Tau benthic epifauna community studied by Tam and Wong was the gastropod Cerithidea djadjariensis. Other gastropods, including C. microptera, Nerita striata, Monodonta labio, Clithon oualaniensis and hermit crabs Uca chlorothalamus crassipes were also reportedly common. The measured epifauna community density was 69.6 per m2– a “low to average” density for the mangals in the overall study. No uncommon infauna/ epifauna was recorded from San Tau (ibid).
The Tung Chung mangal and mudflat is important for littorinid snails such as Littoraria ardouiniana, L. melanostoma and L. pallescens that have been found in abundance there (Lee, 1999).
Table 7.23 Vegetation Community in Tung Chung Bay Mangals (Tam and Wong, 1997)
|
Species |
ST |
TC |
Av |
Species |
ST |
TC |
Av |
|
Kandelia candel |
ü |
ü |
ü |
Clerodendrum inerme |
ü |
ü |
ü |
|
Aegiceras corniculatum |
ü |
ü |
ü |
Cerbera manghas |
ü |
ü |
û |
|
Avicennia marina |
ü |
ü |
ü |
Acrostichum aureum |
û |
ü |
û |
|
Bruguiera gymnorrhiza |
ü |
ü |
ü |
Derris trifoliata |
ü |
ü |
û |
|
Excoecaria agallocha |
ü |
ü |
ü |
Scaevola spp |
ü |
û |
û |
|
Lumnitzera racemosa |
ü |
û |
û |
Pandanus tectorius |
ü |
ü |
ü |
|
Heritiera littoralis |
û |
û |
û |
Suaeda australis |
ü |
ü |
û |
|
Acanthus ilicifolius |
ü |
ü |
ü |
Limonium sinense |
ü |
û |
û |
|
Hibiscus tiliaceus |
ü |
ü |
ü |
Halophila minor |
ü |
û |
û |
|
Thespersia populnea |
ü |
ü |
û |
Zostera japonica |
ü |
û |
û |
Notes: ST = San Tau; TC = Tung Chung; Av = Average presence ( ) / absence (X) in the 43 mangals studied by Tam and Wong.
Source: Adapted from BMT (2002)
There are two species of seagrass in Tung Chung Bay: the annual Halophila minor (also known as H. ovata) and the perennial Zostera japonica. Halophila minor is limited to only four sites in the HKSAR, with San Tau being the only site for this species on Lantau (Fong, 1998a). Although Zostera japonica has been recorded from several locations in Hong Kong, the San Tau mudflat is the only habitat for this species on Lantau (Fong, 1998b). Thus, the San Tau site is ecologically very important for the seagrass community and this is the principal reason for designation of this area as a SSSI.
It was reported that most of the population of these species died during reclamation works for the new airport, although the native population of Z. japonica gradually recovered once airport works were completed (Fong, 1998a). Further investigation at the SSSI in June 1999 reported that the native Z. japonica was again in decline with an area of less than 0.04 m2 remaining, although a transplanted population of this species was reported to have increased from 0.06m2 to 15m2(Fong, 1999a). As Z. japonica is very light sensitive, the reported threats to this species include epiphytic growth and the shading effect of algal blooms. In contrast, as an annual, H. minor recolonised San Tau relatively quickly and was able to extend its coverage with many patches ranging from 3 – 10m in diameter (ibid.). However, it has also been reported that although H. minor is a pioneer species that may colonize some areas in a short time, for the same reason it is also prone to disappearance in response to a ‘catastrophic’ event, such as a change in hydrodynamics or a typhoon event (Fong, 1998b).
Two species of horseshoe crab have previously been recorded from Tung Chung Bay: Tachypleus tridentatus, that uses sandy beaches near the high water level as a breeding site, and Carcinoscorpius rotundicauda that lays eggs in muddy sand and/ or near muddy banks of freshwater channels (Sekiguchi, 1988). These species have also been recorded from adjacent shores along North Lantau, including at Yi O, Tai O, Sham Wat Wan, Shui Hau Wan, Sha Lo Wan and Tai Ho Wan (Huang et al, 1998; Fong, 1999b, Chiu et al., 1999).
It is understood that Tachypleus tridentatus hatch in summer and the larvae usually pass their first winter at the natal beach before moving to nearby mudflat the following spring or summer (Mikkelsen, 1988; Sekiguchi, 1988). Moulting occurs from the second summer (Qin, 1997). In Japan, juveniles of T. tridentatus measuring 1.4 - 7.0 cm in prosoma are known to bury themselves into sandy substrate during high tide and feed on the sand/ mudflat surface at low water (Kawahara, 1982). In the HKSAR, juveniles dwell on the mud for about seven to nine years until a total body length of over 15cm has been reached before they migrate to deeper waters (Qin, 1997).
Less is known about the behaviour of C. rotundicauda, although it is of note that this species was first recorded in the HKSAR on the mudflat at Tung Chung, near Ma Wang Chung (ibid.). This species also lives on mudflats as a juvenile, although little is known of its behavioural ecology in the SAR.
The coastal waters of Tung Chung Bay support a wide diversity of fish species. The most abundant being Mullet Mugil cephalus cephalus and the Tiger Fish Therapon jarbua. It was reported by Mott Connell (2000) that Tung Chung Bay was historically a nursery collection area used by local fish farmers, although this activity was discontinued in the early 1990’s prior to the construction works for the International Airport at Chek Lap Kok.
Other fish species reportedly common in the North Lantau area include anchovy Anchoviella chinensis, sole Cynoglossus spp., the ponyfish Leiognathus brevirostris, snapper Lutjanus spp. and Rabittfish Siganus spp.
The exposed sand and mudflat in between the San Tau and the Tung Chung mangals (as observed at low water on a Spring Tide) is approximately 150m long from the backshore to the low water level.
In cross-section the backshore environment at this location (behind the mudflat) comprises five distinct sub-zones:
1. a belt some 4m wide of rocks/ boulders;
2. a belt some 3m wide of true mangrove comprising mainly Aegiceras corniculatum and Kandelia candel;
3. a 2m wide strip of grass;
4. a zone some 4-5m wide of mangrove associates such as Pandanus tectorius, Scaevola taccada and Clerodendrum inerme; and
5. terrestrial coastal shrub that rose at about 45° to the slopes to the southwest.
Qualitative survey of the mangrove communities at San Tau and Tung Chung mangals concurred with the species listing reported by Tam and Wong (1997). One observation of note made during the Survey was a marked variation in substrate character within the Tung Chung mangal and mudflat and between the Tung Chung mangal and mudflat and that at San Tau.
At the Tung Chung mangal and mudflat small rocks in many areas dominate the backshore substrate and such areas preclude vegetation establishment. It was also noted at the lower zone of the Tung Chung mangal that Zoysia grass was dominant over much of the area and with this the substrate is being increasingly colonised. This has the effect of greatly minimising opportunities for regeneration of adjacent mangroves. In particular, despite the good health and maturity of several adult specimens, numerous propagules of the restricted Bruguiera gymnorrhiza were noted in the grass with no suitable exposed muds in the vicinity for colonisation. In contrast, the flats at San Tau mangal had a more uniform substrate of fine silty mud that favourable for seagrass and mangrove colonisation.
The middle portion of the open mudflat was dominated by the gastropods Cerithidea djadjariensis, Batillaria multiformis, Batillaria zonalis, Nerita striata and Clithon oualaniensis with these species entirely covering the mudflat in some areas. These species were also present in the infauna to a certain extent. Other occasional epifauna species were the mudskipper Periophthalmus cantonensis that was present wherever there were tidal pools and the crab Uca chlorothalamus. The crab Uca lactea was locally dominant at open and elevated (well drained) areas of mudflat near the backshore.
During the course of survey a number of observations were made of shell collection on the exposed flats. It appears that this is largely a commercial exercise. Most activity along the west of Tung Chung Bay where shells taken were predominantly rock oysters Sacostrea cucullata, the mangrove clam Gelloina erosa and various cockles (Cartidae).
Line transects were taken down the mudflat at San Tau and by the Tung Chung mangal in June and July 2002. The results of this Survey, supported by qualitative survey, are presented along with historical data in Annex F- Part I.
The survey recorded 57 juvenile individuals of the Horseshoe Crabs Tachypleus tridentatus, in the vicinity of San Tau SSSI and on the sand and mudflats towards Tung Chung. Two juvenile Carcinoscorpius rotundicauda were found close to the mouth of Tung Chung stream (Figure 7.2 refers).
The average carapace width of all individuals was 4 - 5cm. No eggs or larvae were found, although carapace indentations up to 30cm wide in the sand and sand mounds from burrowing were noted at San Tau. These observations would indicate that the San Tau and Tung Chung flats are important breeding or nursery areas for these species, particularly T. tridentatus. Figure 7.2bshows the locations and abundance of the horseshoe crabs.
Observations of the seagrass beds at San Tau SSSI were also made in June 2002. Two species of seagrasses (Halophila ovata and Zostera japonica) were found and both appeared healthy.
During the Coastal Surveys a number of fish species were recorded from the lower shore and adjacent shallow sub-tidal waters through direct observation, dip netting and from fishermen catches. These are summarised as follows:
· Mudskipper Periophthalmus cantonensis – abundant and widespread
· Tiger Fish Therapon jarbua – abundant and widespread
· Needle Fish Hemiramphus spp. – abundant and widespread
· Mullet Mugil cephalus cephalus – abundant and widespread
· Loach Tridentiger trigoncephalus – abundant but localised
· Rabbitfish Siganus spp. – abundant and widespread
· Goby Glossogobius spp. – abundant but localised
None of the fish species are of conservation concern and all are present in similar habitat across the HKSAR.
The potential terrestrial ecological impacts arising from the proposed development have been identified as set out below:
Construction Phase Impacts
The potential terrestrial ecological impacts arising from the construction activities may include direct impacts due to habitat loss (i.e. loss of woodland vegetation) and indirect impacts due to construction activities such as increased human activities or disturbance (including noise, air quality, water quality impacts, increased risk of hill fires etc). Potential construction phase impacts may arise from:
· site clearance resulting in habitat loss;
· site clearance resulting in fragmentation of habitat;
· construction resulting in wastes, pollutants and excavated material that may impacts on stream habitats by pollution, erosion and/ or sedimentation;
· disturbance to flora and fauna from human activities including construction machinery or helicopter noise, air quality from machinery and water quality from run-off of exposed soil and
· water extraction from streams for construction may impact on stream habitats (although it is noted that this is not permitted in the Country Park).
The construction phase impacts with vary according to the construction methods, both construction of towers and alignments stations using helicopter and construction using the material ropeway are discussed.
Operation Phase Impacts
The potential terrestrial ecological impacts arising from operation of the cable car may arise from:
· increased noise and disturbance from the operation of the cable car including maintenance;
· increased litter and waste;
· increased visitors to Tung Chung and Ngong Ping and use of the emergency rescue trail;
· uncontrolled hill fires;
· glare/lighting (night maintenance);
· impact of structures (towers and cables) on bird species; and
· indirect habitat loss and damage.
The significance of ecological impacts have been evaluated based on the criteria specified in Table 1, Annex 8 of the TMEIA, as follows:
· habitat quality;
· species affected;
· size/ abundance of species and habitats affected;
· duration of impacts;
· reversibility of impacts; and
· magnitude of environmental changes.
Impacts are classified as ‘insignificant’, ‘minor’, ‘moderate, ‘severe’ or ‘extremely severe’, The classification of a given impact will vary based on the criteria listed above. For example, an impact might be ranked as ‘minor’ if it affected only common species and habitats, or if it affected only small numbers of individuals or small areas, whereas it might be ranked as ‘severe’ if it affected rare species or habitats, large numbers of individuals or large areas. The major factors giving rise to a ranking are stated in the text as far as possible. As noted in Annex 16 of the TM, a degree of professional judgement is involved in the evaluation of impacts.
Impacts to species or groups assessed as ‘minor’ are predicted to cause a slight, and/ or short-term reduction in the local population numbers or geographic distribution of a species or group, but the species or groups are predicted to recover from the perturbation with no long-term adverse impacts. Habitat impacts are considered ‘minor’ when no species of conservation or regulatory concern are found, and when the habitat in question was widely distributed locally.
Impacts to species or groups assessed as ‘moderate’ are predicted to cause local reduction of species or group population numbers. The reductions would be long-term, and probably not recoverable, but the species or groups in question are considered widely distributed or common, and abundant on a local, regional, or global scale. Habitat impacts are judged ‘moderate’ when the habitat in question was of limited local or regional distribution or declining in extent, and when the potential for the habitat to support fauna and flora was considered of conservation or regulatory importance.
Impacts to species or groups are assessed as ‘severe’ when they are assesed to adversely affect species or groups that are of conservation or regulatory concern locally, regionally, or globally due to scarcity or declining population or distribution trends. Impacts to habitats are considered ‘severe’ when the habitats are found to be limited or declining in geographic distribution, contain plant species of regulatory or conservation concern, or are generally considered to be of local, regional or global importance to the support of wild fauna.
Impacts to species or groups are assessed as ‘extremely severe’ when they are assessed to have an irreversible impact on species or groups that are of conservation or regulatory concern locally, regionally, or globally due to scarcity or declining population or distribution trends.. Impacts to habitats are considered ‘extremely severe’ when irreversible impacts may occur to habitats that are found to be limited or rapidly declining in geographic distribution, contain plant species of regulatory or conservation concern, or are generally considered by the scientific community to be of local, regional or global importance to the support of wild fauna. This impact classification is usually given to highly restricted/ endangered species or habitats.
In accordance with the TM, if ecological impacts are found to be significant (i.e. minor to severe) mitigation needs to be carried out. Mitigation measures are not required for insignificant impacts. As a general rule, the management of ecological impacts should be (in order of priority): impact avoidance, impact minimisation and impact compensation. Impact avoidance usually consists of modifications to the design of the Project, but in extreme cases may require abandonment of the Project. Impact minimisation includes any means of reducing the scope or severity of a given impact, e.g. through timing of construction works, modification in design, or ecological restoration of disturbed areas following the completion of works. Impact compensation assumes that an irreversible impact will occur upon a given habitat or species and attempts to compensate for it elsewhere, for example, by enhancement or creation of suitable habitat. Compensation may take place on-site or off-site.
Construction of the alignment (tower locations) and terminal locations will result in permanent loss of habitat. There will be an additional temporary loss resulting from the construction of rescue trail and access tracks, works areas and temporary work sites. The temporary areas will not be permanently occupied and may, therefore, be left to re-establish naturally or be re-instated once the construction works have been completed.
In calculating the permanent and temporary areas of habitat lost, all towers, angle stations, terminal locations and the rescue trail including all slopes and embankments have been regarded as permanent loss. All construction areas adjacent to these locations are assumed to be temporarily lost.
Habitat evaluation is based on the criteria specified in Table 2, Annex 8 of the TMEIA:
· naturalness;
· size;
· diversity;
· rarity;
· re-creatability;
· fragmentation;
· ecological linkage;
· potential value;
· nursery/ breeding ground;
· age; and
· abundance/ richness of wildlife.
The TMEIA (Annex 8) identifies important habitat types in the territory:
· mature native woodland larger than one hectare;
· undisturbed natural coastal area larger than one hectare or longer than 500 metres in linear measurement;
· inter-tidal mudflats larger than one hectare;
· established mangrove stands of any size;
· brackish freshwater marshes larger than one hectare;
· established seagrass beds of any size;
· natural stream courses and rivers longer than 500 metres;
· established coral communities of any size; and
· other habitats found to have special conservation importance by documented scientific studies.
Impacts on species found within habitats have also been evaluated based on the criteria specified in Table 3, Annex 8 of the TMEIA:
· protection status;
· distribution; and
· rarity.
Construction phase impacts have been assessed and evaluated against the major impacts associated with linear projects, namely habitat loss, habitat fragmentation, and disturbance (English Nature, 1994; Reijnen et al., 1995; Treweek, 1999). Construction phase impacts to ecology are broadly related to:
· direct habitat loss;
· fragmentation of habitat; and
· disturbance from construction activities.
Indirect impacts relate to the effect of habitat loss and subsequent reduction of food resources and breeding sites. A potential impact is due to disturbance and direct habitat loss during construction. Although the more mobile species present will avoid the disturbed areas, certain amphibian, fish and damselfly species have restricted mobility and specific habitat requirements. Further details on these aspects are discussed below.
Habitat loss is a potential threat to many species as it may be linked to direct mortality, species displacement, and is most severe in species that have an inability to translocate to suitable habitat elsewhere (Treweek, 1999). Although species-area relationships have been extensively studied (larger areas of habitat generally provide an area for a greater number of species), it is difficult to estimate the minimum area of habitat required for most animals and this is more difficult with highly mobile species such as birds. Where the alignment passes through high value habitat such as woodland, the Emergency Rescue Trail and tower locations will be consistent with functional objectives, so that habitat loss is no more than is absolutely necessary.
The habitat loss of the Project is presented below in Table 7.24. Permanent habitat loss comprises the area within the immediate footprint of the permanent works. The Table represents the worst-case scenario; the actual permanent vegetation loss is dependant on the tower footing designs and the subsequent area available for re-vegetation.
Table 7.24 Approximate Habitat Loss Arising from the Project (ha)
|
Description and Location (and Totals) |
Study Area (permanent loss) (ha) |
Study Area (temporary loss) (ha) |
Total |
|
|
Grassland |
Nei Lak Shan Angle Station |
0.20 |
0.26 |
0.46 |
|
|
Tower 6 |
0.01 |
0.13 |
0.14 |
|
|
Emergency Rescue Trail |
0.30 |
0.03 |
0.33 |
|
|
Touch Down Point (3) |
0.00 |
0.10 |
0.10 |
|
|
Total HC |
0.51 |
0.52 |
1.03 |
|
|
Total MRC |
0.00 |
0.03 |
0.03 |
|
|
Total |
0.51 |
0.55 |
1.06 |
|
Low shrub |
Tower 3 |
0.01 |
0.13 |
0.14 |
|
|
Tower 4 |
0.01 |
0.13 |
0.14 |
|
|
Tower 5 |
0.01 |
0.13 |
0.14 |
|
|
Tower 7 |
0.01 |
0.13 |
0.14 |
|
|
Ngong Ping Terminal |
0.30 |
0.09 |
0.39 |
|
|
Emergency Rescue Trail |
0.30 |
0.03 |
0.33 |
|
|
Total HC |
0.64 |
0.64 |
1.28 |
|
|
Total MRC |
0.00 |
0.01 |
0.01 |
|
|
Total |
0.64 |
0.65 |
1.29 |
|
Tall shrub |
Emergency Rescue Trail |
0.09 |
0.01 |
0.10 |
|
|
Total HC |
0.09 |
0.01 |
0.10 |
|
|
Total MRC |
0.00 |
0.03 |
0.03 |
|
|
Total |
0.09 |
0.04 |
0.13 |
|
Woodland |
Emergency Rescue Trail |
0.03 |
0.09 |
0.12 |
|
|
Total HC |
0.03 |
0.09 |
0.12 |
|
|
Total MRC |
0.00 |
0.00 |
0.00 |
|
|
Total |
0.03 |
0.09 |
0.12 |
|
Plantation |
Airport Island Angle Station |
0.30 |
0.06 |
0.36 |
|
Stream |
Ngong Ping Terminal |
0.00 |
30m* |
30m* |
|
Developed area |
Tung Chung Terminal |
1.50 |
0.25 |
1.75 |
|
|
Tower 1 |
0.01 |
0.13 |
0.14 |
|
|
Airport Island Angle Station |
0.30 |
0.06 |
0.36 |
|
|
Tower 2A |
0.01 |
0.13 |
0.14 |
|
|
Tower 2B |
0.01 |
0.13 |
0.14 |
|
|
Emergency Rescue Trail |
0.02 |
0.01 |
0.03 |
|
|
Total HC |
1.85 |
0.71 |
2.56 |
|
|
Total MRC |
0.00 |
0.00 |
0.00 |
|
|
Total |
1.85 |
0.71 |
2.56 |
|
Total HC |
|
3.42 |
2.03 |
5.45 |
|
Total MRC |
|
0.00 |
0.07 |
0.07 |
|
Total Loss |
|
3.42 |
2.10 |
5.52 |
Note: MRC: Material Ropeway Construction
HC: Helicopter Construction
*: Indicates the approximate length of the stream that will be disturbed
The values provided in this table are based on the tower base size, terminal location, Angle stations and their respective anticipated construction area. The figures listed are provided as an approximate indication of the potential habitat loss. The areas have been calculated from the proposed construction areas while the Emergency Rescue Trail has been calculated from Figure 7.3.
Source: Information adapted from MTRC Land Use Map and Figure 7.3
· marsh;
· cultivation;
· coastal waters;
· mangrove; and
· mudflat.
Habitats of particular ecological interest in the Study Area include native species-rich tall shrub, natural secondary woodland, coastal waters, mangrove and streams. Other habitats within the Study Area are of lower ecological value, which include grassland and low shrub. Complete clearance will be required for buildings to be constructed on the terminus sites and temporary clearance will be required for tower bases. The degree and severity of the impacts depend on the specific habitats affected. The amount of vegetation to be removed is minor compared with other linear projects such as road developments.
Helicopter Construction Method
Grassland habitat will be cleared for the proposed footprints of Tower 6 and the Nei Lak Shan Angle Station.
The baseline ecological survey indicated that grassland communities dominate the Study Area and generally evaluated as of low to medium ecological value as a habitat. However, it should be noted that they have the potential to support a rare and/or protected plant species such as orchids (such as the protected common orchid Arundina graminifoli). A protected (but common) orchid species Arundina chinensis was recorded in the vicinity of the proposed angle station location.
In the vicinity of the angle station the uncommon and localised King Cobra Ophiophagus hannah species was observed (indirectly) in grassland habitat in the vicinity of the angle station. It is unlikely to contain significant breeding or feeding habitat for rare or protected species. The presence of the protected species will be discussed in Section 7.8.5 (Key Fauna Species).
Approximately one hectare of grassland habitat will be cleared. Considering the extent of grassland habitats in the local area and region and the criteria specified in Table 2, Annex 8 of the TMEIA used for habitat evaluation, minimal ecological impact is anticipated from grassland habitat removal.
Material Ropeway Construction Method
The Material Ropeway will have impacts on grassland as that of the helicopter construction (as stated above) as well as additional impacts to vegetation during the construction and operation of the Material Ropeway.
Additional clearing requirements at M8, M9, M12, M13, M14, M15 and M18 will be insignificant as the construction of the tower locations for the Material Ropeway are anticipated to be only approximately 0.03ha. Minimal ecological impact is anticipated from grassland habitat removal.
Helicopter Construction Method
Marsh habitat is located near the Angle Station (refer to Figure 7.3). The marsh community is of moderate ecological value. No infrastructure or access requirements are located in marsh habitat. No rare or protected flora was recorded in this habitat along the development footprint.
Material Ropeway Construction
The Material Ropeway will have impacts on marsh habitat as that of the helicopter construction (as stated above), habitat loss is not expected.
Helicopter Construction Method
This habitat type characterizes the vegetation communities in the vicinity of proposed Tower locations 3, 4, 5 and 7.
The common species in this habitat type include the trees Machilus chekiangensis, Rhus succedeana, Sterculia lanceolata, Schefflera octophylla and Sapium discolor interspersed with a number of shrub species. Species of conservation note (rare and protected) recorded in this habitat include a single specimen of Camellia sinensis located just outside the constuction zone for Tower 4. Records of synergies for laval food plants and nectar sources were recorded between the White Commodore Parasarpa dudu and two adult food plants – Rhaphiolepsis indica and Zanthoxylum avicennae located at the Tower 4 location, and the R. indica was recorded at Tower 3. Loss of habitat will result in a reduction in available nectar sources for adult butterflies. However, no evidence of the relatively sessile larvae was noted and no significant impact to known larval food plants is anticipated.
The impact is expected to be insignificant as the adult butterflies have moderate to high mobility and should be able to utilise other nectar sources in the vicinity. The presence of protected and rare species will be discussed in Section 7.8.5 (Key Fauna Species).
Approximately one hectare of low shrub habitat at three tower locations will be cleared. Considering the extent of low shrub habitats in the local area and region and the criteria specified in Table 2, Annex 8 of the TMEIA used for habitat evaluation, minimal ecological impact is anticipated from low shrub habitat removal.
Material Ropeway Construction Method
The Material Ropeway will have impacts on low shrub as that of the helicopter construction (as stated above) as well as additional impacts to vegetation during the construction and operation of the Material Ropeway. Additional clearing requirements at M1, M2, M3, M5, M6 and M7 will be minor as the construction of the tower locations for the Material Ropeway are anticipated to be only approximately 0.01ha at these locations. Minimal ecological impact is anticipated from low shrub removal.
Considering the extent of grassland habitats in the local area and region and the criteria specified in Table 2, Annex 8 of the TMEIA used for habitat evaluation, minimal ecological impact is anticipated from low shrub habitat removal
Helicopter Construction Method
A number of tall shrub communities are present within the Study Area. Although the habitat is fragmented, the communities rated moderate to high in habitat evaluations made for the Project. The emergency rescue trail will result in a small amount of tall shrub to be cleared at the following locations (0.10ha) (refer to Figure 7.3):
· adjacent to mangrove/ mudflat (between Tower 2 and Tower 3); and
· between Tower 3 and Tower 4 a small section of tall scrub;
No rare or protected flora was recorded in this habitat along the development footprint. The potential impact is considered moderate, however mitigation measures should minimise any ecological impacts. Clearing these habitats will require mitigation (compensatory planting).
Material Ropeway Construction Method
The Material Ropeway will have impacts on tall shrub as that of the helicopter construction (as stated above) as well as additional impacts to vegetation during the construction and operation of the Material Ropeway.
Additional clearing requirements at: M4, M10, M11, M16 and M17 will be required. The construction of the towers for the Material Ropeway is anticipated to be approximately 0.03ha. At these locations as tall shrub habitat is considered moderate to high ecological value. It is anticipated that the impact will be moderate (although it is temporary) due to the disturbance caused. Clearing these habitats will require mitigation (compensatory planting).
Helicopter Construction Method
Secondary woodland, when covering an area greater than one hectare, is classed as important in Annex 8 of the TMEIA. A number of woodland communities (greater than one hectare) are present within the Study Area. The communities rated highly in habitat evaluations made for the Project. A total of approximately 105ha of this habitat is present within the Study Area:
· the downward slopes west of the Ngong Ping plateau;
· the downward slopes east of the Nei Lak Shan ridge to the west of Tung Chung Bay; through San Tau Valley; and
· pockets of Woodland habitat growing beside tall shrub habitat in upland area where there are perennial hill streams
A very small amount of woodland will be disturbed for the construction of the Emergency Rescue Trail (refer to Figure 7.3). No rare or protected flora was recorded in this habitat along the development footprint.
Habitat loss is a threat to birds as it may be linked to direct mortality, species displacement, and is most severe in species that have an inability to translocate to suitable habitat elsewhere. Although there is potential for some loss of higher quality woodland habitat that is utilised by birds, the overall impact of losing the woodlands present in the Study Area on bird populations is likely to be insignificant.
In particular three birds of conservation interest, Eagle Owl (Bubo bubo), Red-throated Flycatcher (Ficedula albicilla) Pale-legged Leaf Warbler (P. tenellipes) have been recorded in woodland in the Study Area. The impacts associated with habitat removal to species of conservation interest are discussed in Section 7.8.5 (Key Fauna Species).
In general due to the limited extent of habitat removal (approximately 0.12ha) impacts are considered moderate. Clearing these habitats will require mitigation (compensatory planting).
Material Ropeway Construction Method
The Material Ropeway will have impacts on woodland as that of the helicopter construction (as stated above).
Helicopter Construction Method
Plantation woodland occurs at the Airport Island Angle Station. The community is evaluated as of low value. Approximately 0.36ha will be temporarily disturbed and permanently lost from the construction of the as Airport Island Angle Station. This is a re-createable man-made habitat, containing several naturalised exotics, and impacts from habitat loss are considered insignificant.
Material Ropeway Construction Method
The Material Ropeway will not require the removal of any plantation woodland.
Construction using Helicopters
Abandoned cultivated land is not present at any proposed construction locations; however is present in the vicinity of the proposed Ngong Ping Terminal. There were no flora species on conservation note within this habitat type. No impacts associated with the removal of abandoned cultivated land to species of conservation interest are considered to be significant as a result of the proposed development.
Construction using a Material Ropeway
The Material Ropeway will not require the removal of any abandoned cultivation.
Construction using Helicopters
In general, very small areas of stream habitat will be removed as part of construction activities. The disturbance to streams will occur at:
· the Ngong Ping terminal; and
· streams crossed by the Emergency Rescue Trail (Sham Wat Stream 2, 3 and 4).
Streams in the area generally have high conservation value as they provide habitat (for breeding and feeding) for a wide range of fauna species and in particular amphibian, fish and invertebrate species. Construction impacts on small streams as the streams crossed by the Emergency Rescue Trail may have a potential to impact the natural streambed, with potential deleterious impacts (crushing, displacement, and entrapment) on sedentary aquatic fauna such as tadpoles of amphibian taxa. Also the destruction of riparian vegetation with deleterious impact on amphibians (e.g. the Short-legged Toad) for which riparian vegetation is a highly important habitat, particularly during the breeding season, which lasts from March to August but peaks during April to June.
Although the Ngong Ping Stream has poor water quality (i.e. visible hydrocarbon sheen on the surface) as it collects run-off from the developed areas and roads including domestic wastewater, the stream habitat has a high potential ecological value (particularly downstream). A number of species of conservation interest have been recorded in Ngong Ping that utilise the stream, the potential impact to species are described in Section 7.8.5 (Key Fauna Species). Mitigation measures for the stream are described in detail in Section 7.11 these measures include:
· the provision of sewage treatment as part of the proposed Ngong Ping Sewage Treatment Plant which will diminish the pollution load considerably; and
· the recommendation for stream modification and improvement (design with consultation from community groups and Government Agencies), which if implemented along the conservation guidelines included in Section 5, may significantly improve water quality and natural stream habitat in the area.
As discussed in Section 5 (Water Quality) the proposed terminal location is located within approximately 30m of stream. The modification to the stream (modification/ improvement works) at the stream may potentially impact on species located downstream. However is considered that with mitigation measures identified with Section 5 no impacts would result to fauna species.
Species of conservation interest have been recorded in streams in the vicinity of the proposed Emergency Rescue Trail (Sham Wat Stream 2, 3 and 4), the potential impacts to species are described in Section 7.8.5 (Key Fauna Species). The impact of habitat loss is considered moderate for streams, as no stream bed will be lost in the Lantau North Country Park (and extension) and only a very narrow band of riparian vegetation will have to be removed (the width of the Emergency Rescue Trail. Also based upon, the number of aquatic species of conservation interest recorded (amphibians) and also the size of habitat lost, the impacts are predicted to be moderate, although the impacts will be insignificant, provided that appropriate mitigation measures are undertaken (described in detail in Section 7.11).
Construction using a Material Ropeway
The Material Ropeway will have impacts on grassland as that of the helicopter construction (as stated above) as well as additional impacts to vegetation during the construction and operation of the Material Ropeway. The Material Ropeway will not require the removal of any stream habitat.
Habitat Impacts Summary
A summary of the habitat removal impacts is provided in Table 7.25 below.
Table 7.25 Summary of Predicted Impacts on Habitats within the Study Area
|
Habitat/ Vegetation Community |
Importance/Evaluation |
Summary of Potential Impacts |
Impact Evaluation |
|
|
Helicopter Construction Method |
Material Rope-Way Construction Method |
|||
|
Grassland |
Low |
Grassland habitat dominates much of the alignment (with low shrub); it generally has the lowest ecological significance of the communities present in the Study Area (apart from developed areas). The grassland habitat that will be disturbed during construction activities will be at Tower 6, the Angle Station and along the Emergency Rescue Trail. A number of protected but common Orchid species may be impacted upon. Overall less than one ha require removal.
|
Minor impact |
Minor impact |
|
Marsh |
Moderate |
Marsh is not located within close proximity to any proposed construction areas and will not be disturbed during construction or operation of the Project.
|
Noimpact |
Noimpact |
|
Low shrub |
Low |
Low shrub habitat dominates much of the alignment (with grassland). It will be disturbed during construction activities at a number of tower locations (2, 3, 4, 5 and 7) and the Emergency Rescue Trail. Overall only 0.4 ha require removal.
|
Minor impact |
Minor impact |
|
Tall shrub |
Moderate to High |
Tall shrub will be disturbed by the construction of the Emergency Rescue Trail during construction activities. The narrow nature of the trail will result in a small area required to be cleared (i.e. less than 0.5ha). No protected or rare species will be destroyed during construction of the trail. Additional impacts (especially general disturbance) from the Material Rope-Way construction method.
|
Moderateimpact |
Moderate impact |
|
Woodland |
High (+1ha) |
Woodland will be disturbed by the construction of the Emergency Rescue Trail during construction activities. The narrow nature of the trail will result in negligible clearing for the scale of the Project (i.e. less than 0.5ha). No protected or rare species will be destroyed during construction of the trail.
|
Moderate impact |
Moderate impact |
|
Plantation |
Low |
Plantation will be disturbed at the Airport Angle Station minimal clearing is required in plantation habitat and it is not anticipated that any fauna will be significantly impacted upon.
|
Minor impact |
Minor impact |
|
Cultivation |
Low |
Cultivation is not located within close proximity to any proposed construction areas and will not be disturbed during construction or operation of the Project.
|
Insignificantimpact |
Insignificantimpact |
|
Abandoned cultivation |
Moderate |
Abandoned cultivation will not be significantly impacted on by any proposed construction areas.
|
Insignificantimpact |
Insignificantimpact |
|
Streams |
High
(moderate to high for the Ngong Ping stream) |
The Stream habitat in the Study Area generally supports a wide diversity of species including species of conservation significance: · Lesser Spiny Frog Rana exilispinosa at Ngong Ping · Three striped Grass Frog Rana macrodactyla Sham Wat Stream · Green Cascade Frog Rana Livida west of the Ngong Ping Plateau in SWS 2. Impact from construction near the stream at the Ngong Ping Terminal and the Emergency Rescue Trail may cause impacts if recommended mitigation measures are not followed. |
Moderate impact |
Moderate impact |
|
Mangrove |
High |
The cable car will be suspended above mangrove communities (Tower 2 and 3). This habitat and fauna species using this habitat will only temporally impacted (bird species) upon during construction from helicopter disturbance (noise impacts).
|
Insignificantimpact |
Insignificantimpact |
|
Mudflat |
High |
Will not be disturbed during construction or operation of the Project.
|
Insignificantimpact |
Insignificantimpact |
|
Coastal Waters |
High |
Will not be disturbed during construction or operation of the Project.
|
Insignificantimpact |
Insignificantimpact |
|
Developed Area |
Low (very low) |
Developed areas have a very low habitat value.
|
Insignificantimpact |
Insignificantimpact |
Habitat fragmentation (i.e. the breaking down of existing habitat into smaller areas of habitat) is often associated with linear construction projects such as roads, transmission lines and cable cars. Fragmentation of habitats, such as woodlands, is known to lead to the reduction in numbers of fauna species.
Construction activities have the potential to fragment and isolate areas of habitat. In general the more fragmented a habitat, the lower the ecological value. Portions of habitat present in the Study Area are already fragmented such as the woodland and tall shrub communities that are often narrow and discontinuous corridors following steep gullies and streams or ‘patches’ in the Study Area. The grassland and low shrub habitats are relatively continuous throughout the landscape.
Construction using Helicopters
As discussed in Section 7.8.5 (Key Fauna Species) the proposed cable car infrastructure will not require significant clearing of vegetation, particularly of woodland and tall shrub habitats where fragmentation impacts are generally greater than that of grassland and low shrubland. The amount of vegetation cleared (in non-developed) areas is approximately 2.7ha and subsequently habitat fragmentation is not considered a significant impact to fauna species.
Construction using a Material Ropeway
The Material Ropeway will have the additional construction impacts (clearing etc) but it is considered to have minor increase in fragmentation, as only a small area of habitat requires removal.
Rescue Trail
The Emergency Rescue trail will fragment some habitats although only a small area of habitat requires removal (the path has a maximum width of 1.5m). The location of greatest disturbance will be in woodland habitat near Tower 3. The impacts are considered low to moderate and are described in the Operational Phase Impact Section (barrier to fauna movement).
During construction and operation of the Project disturbance to flora and fauna may occur. . Disturbance during the construction phase is likely to be associated with construction machinery and the increased presence of human activities on-site.
Short-term disturbance can affect the time species have available for feeding, whilst longer-term effects can cause a reduction in the use of a particular area for feeding and/ or breeding (Treweek, 1999). Many animal populations can gradually habituate to low levels of disturbance and transient constructional phase impacts are not predicted to be significant to fauna present, provided that all measures are taken to ensure that disturbance is kept to a minimum. Temporary noise impacts may have a significant short-term impact to wildlife at the tower locations, Angle Station locations.
Disturbances that have the potential to impact on flora and fauna species during the construction phase are:
· waste and contamination;
· soil erosion and sedimentation;
· air pollution (dust);
· trampling of grass and shrub species;
· fire regime;
· noise and lighting; and
· extraction of water from watercourses.
Waste and contamination impacts resulting from construction have the potential to occur if no management or mitigation measures are implemented during construction (considered in Section 6). The impacts may range from general litter left on site, which can migrate into waterways to more serious impacts such as fuel or chemical spills. Although mitigation measures should ensure that minimal impact occurs to grassland communities the particular areas that are risk of contamination are stream habitats (which are near Tower locations and near the Emergency Rescue Trail), the locations are:
· Tower 1, 2A and 2B (adjacent to the marine environment);
· Tower 3 (adjacent and up-slope to two small stream not named);
· Tower 5 Angle Station and Tower 6 (adjacent and up-slope to the STS);
· Tower 7 (in the vicinity – up-slope to SWS 2 and SWS 3)
· Ngong Ping Terminal (SWS 1 through the proposed terminal site); and
· Emergency Rescue Trail (at a number of locations including SWS 2, 3, 4 and within proximity to the locations noted above).
The receiving environments are sensitive to wastes and contamination particularly stream habitats and impact to native amphibian species. The potential impact is considered as moderate due to the potential for uncommon, rare and endangered species to be affected. A spill management plan is given in Section 5.
The Material Ropeway would have a number of towers in the vicinity of streams (refer to Figure 7.3). Although the amount of waste and contamination from these towers is expected to be minimal, it is noted that the method has the potential to cause disturbance during construction and dismantling of the ropeway to have impacts to sensitive stream environments.
Clearance of vegetation will be required for construction (excavation of foundations), Emergency Rescue Trail and termini. The exposure of soil surfaces during these operations will create the potential for soil erosion and subsequent water quality and sedimentation impacts on stream habitats.
This impact could be severe in sites, which are prone to impact, for sites that are unstable or are exposed locations and steeply sloping sites. The particular areas that are risk of impacts from soils and erosion are stream habitats (which are near Tower locations and near the Emergency Rescue trail), the locations are:
· Tower 1, 2A and 2B (adjacent to the marine environment);
· Tower 3 (adjacent and up-slope to two small stream not named);
· Tower 4 (very steep slope);
· Tower 5 Angle Station and Tower 6 (adjacent and up-slope to the STS);
· Tower 7 (very steep slope in the vicinity – up-slope to SWS 2 and SWS 3)
· Ngong Ping Terminal (SWS 1 through the proposed terminal site); and
· Emergency Rescue Trail (at a number of locations including SWS 2, 3, 4 and within proximity to the locations noted above).
The receiving environments are sensitive to water quality and sedimentation impacts particularly stream habitats and associated flora and fauna species; particularly amphibian species such as the Short-legged Toad Megophrys brachykolos at Ngong Ping and SWS feeder stream 4 and Romer’s Tree Frog Philautus romeri atNgong Ping.
The Material Ropeway would have a number of construction zones in the vicinity of streams (refer to Figure 7.3). It is anticipated that this construction method would have an increased potential for erosion and sedimentation and subsequent impact on stream quality including amphibian species.
Construction activities can be expected to create increased air pollution, which could affect plants and habitats nearby. For example machinery exhaust and dust can cause vegetation damage, which may have a secondary impact on fauna (i.e. the availability of food/ habitat plants may be diminished). In severe cases of poor atmospheric pollution animals can be affected, such as nesting birds.
Whilst there may be increased dust during construction that may affect flora and fauna, this considered a minor impact. The air quality impacts (as discussed in Section 3) are likely to be temporary and small, given the construction methods and localised nature of the earthworks.
It is anticipated that trampling of grass and shrub species may occur outside the designed work areas. Access to tower sites will require traversing habitat from existing Country Park Trails. Impact on the immediate trail path will trample a number of species. Mitigation measures for new paths and their alignment (for safety as well as ecological aspects such as species, path diameter, utilisation for future safety trails, path erosion has a low potential) to ensure that impacts are minimised.
Grassland habitats are vegetation communities modified and maintained as grasslands by thin/ infertile soils, soil erosion and fires. Short term disturbance from waste and impacts/ or can be returned to grassland communities relatively easily.
The location of the marsh area (located near existing path) indicates that marsh habitat is sufficient distance from the nearest construction site (over 100 metres east from the nearest tower/ angle station location). It is anticipated that the marsh will not be impacted upon by construction activities. The location of the woodland area (located near existing country path) indicates that woodland habitat is sufficient distance from the nearest construction site (over 100 metres from the nearest tower/ angle station location). It is anticipated that the woodland will not be impacted upon by construction activities.
The Material Ropeway construction and assembly is expected to have an increased impact on habitats from the trampling of grass and shrub species. The creation of a parallel alignment will have impacts at a number of locations.
A number of tower sites are located within areas that are prone to hill fires. However, it has been noted that only one or two hill fires have been recorded in this area within the last 10 years.
Within the Study Area smoking, cooking, use of machinery and the use of stoves during the construction period may accidentally cause hill fires. It should be noted that it is prohibited to carry a lantern, cooking stove and or to discard any match, lighted cigarette in a manner likely to cause a fire in Country Parks. The regular burning of vegetation hinders natural succession of the vegetation from grassland, through to shrubland and woodland. The natural climax vegetation in the SAR is woodland but much of the vegetation remains as grassland due to regular burning.
No evidence is present to suggest that the fire frequency and intensity will increase. Mitigation measures during construction will minimise the risk of accidental hill fire.
Fauna response to noise results from a wide range of variables including characteristics of the noise duration, life history characteristics of the species, habitat type, season and activity of the animal (i.e. feeding, breeding, sex and age, previous exposure and whether other physical stressors (e.g. drought) are present (Manci, et al., 1988).
Long-term exposure to noise can cause excessive stimulation to the nervous system and chronic stress that is harmful to the health of wildlife species and their reproductive fitness (Fletcher, 1980; 1990). Behavioural responses vary among species of animals and birds and among individuals of a particular species. Variations in response may be due to temperament, sex, age, and prior experience with noise. Panic and escape behaviour results from more severe disturbances (National Park Service, 1994).
Although there are relatively few studies that have quantified the effects of disturbance on wildlife, there is evidence to suggest that birds (Hill et al., 1997) and mammals such as deer are prone to disturbance associated with human activity (English Nature, 1994). Disturbance impacts are difficult to quantify as many species appear to habituate to disturbances (Treweek, 1999). Hill et al. (1997), however, discussed gradients of responses to disturbance impacts in birds. They concluded that depending on the intensity, frequency and duration, disturbance impacts were greatest during high-intensity activity (especially high amplitude ‘startling’ noises associated with activity such as shooting).
The use of a helicopter has a potential to disrupt fauna species in the area. Little relevant literature is available on the effects of helicopter noise on wildlife and the available literature tends to focus on individual species in other world regions. The study of animal response to noise is a function of many variables including characteristics of the noise and duration, life history characteristics of the species, habitat type, season and current activity of the animal, sex and age, previous exposure and whether other physical stressors (e.g. drought) are present (Manci, et al., 1988).
Disturbance pressures are likely to be greater for nocturnal species that are unaccustomed to pressures such as high levels of noise, artificial lighting and human activity. Little literature is available that has quantified the effects of nocturnal disruption, there is still the possibility that disturbance could effect species such as frogs and toad.
There is the potential for a reduction in the breeding success due to mating calls being drowned out by loud noises during construction from the operation of machinery. There is also the possibility that such disturbance will cause the frogs to delay their breeding activities until after the disturbance has ended, i.e. after 8.00pm. Thus the length of time available for breeding will be curtailed. These are, however, worst-case scenarios and it is likely that noise will be within tolerable levels during daylight hours and no construction activities will occur at the Tower locations outside daylight hours. Disturbance caused by construction noise during normal operating hours for construction work (i.e. 6.00am to 8.00pm) is considered to represent an insignificant impact to herpetofauna. The impacts outside these times are largely unknown and the precautionary principle should be enforced.
Mammal species such as Barking Deer, Ferret Badger and Civets are sensitive to noise and visual disturbance and generally avoid noisy areas. Mobile fauna can disperse between adjacent areas of habitat (necessary for important ecological processes such as foraging, migration and breeding) and the periods at dawn and during the middle of the night are likely to be important for such activities. These animals are also primarily active at night, during which time no noise (after 8.00pm) associated with the cable car is likely to be present. It is therefore considered that the impact of noise and visual disturbance on the foraging behaviour of larger mammals will be insignificant.
Although the effects of disturbance on birds are difficult to quantify, many bird species in Hong Kong (and elsewhere) are known to habituate to disturbance and noise. It is, therefore, unlikely that bird species present in the Study Area will suffer significant disturbance effects attributable to the project and, as such, these construction phase disturbance impacts are considered to be insignificant.
In summary, working up to 8.00pm (no noisy activities between 8.00pm and 11.00pm – noisy activities include the use of powered mechanical equipment for construction), but ceasing work between 11.00pm and 7.00am, is considered a sufficient window to allow nocturnal species such as mammals, birds and herpetofauna time for dispersion between habitats. There is also likely to be an overall ecological gain from extending the working hours to 11.00pm, as this will shorten the construction period. Based upon this, extending the works up until 11.00pm is not predicted to give rise to additional significant impact to fauna in the Study Area. The mitigation of impacts from construction activities recommended in the EIA for daytime activities should ensure that the impacts are at an acceptable low level during the evening-night period (as described in Section 4).
Lighting from construction sites has the potential to disrupt certain fauna species. It is anticipated that species will temporally relocate from the near vicinity. The small nature of the each tower site (1225m3) and that the nature of the construction work (generally construction work it will be at a centralised point and the lights will be highly directional, rather than a linear alignment). This enables amphibian, reptile and mammal species to relocate to adjacent areas easily. This temporary relocation from a localised vicinity will have impacts that are not readily identified the number of species affected will be minimal. In grassland the nature of the sight and species present will impact upon sessile species.
Water may be required for a number of procedures during construction, including the mixing concrete. It is possible that, as the work areas are remote that contractors, for convenience will wish to use small pumps into local streams to easily get water to tower construction sites (although it is not permitted under the Country Parks Regulations).
Based upon both wet and dry season field surveys, numerous streams in the Study Area are seasonal, or have a very low flow base. The extraction of quantities of water from existing watercourses to an extent that the downstream flow is diminished could cause significant (high) impacts to flora and fauna species, particularly amphibian species.
The composition of the terrestrial animal community is largely dependent on the floral structure and species composition of the habitats present (Dudgeon and Corlett, 1994). The Study Area contains a large number of faunal species of conservation interest, particularly species associated with freshwater habitats. There is a concomitant requirement to preserve habitat integrity as a necessary prerequisite for species conservation, in particular narrow belts of riparian vegetation, which are important wildlife corridors.
For individual animal species, impacts (particularly construction phase impacts) generally will be higher for species that have lower avoidance ability, either due to having very specific habitat requirements or low locomotory capability, or both. These factors are summarised in Table 7.26 below for the species of conservation interest recorded in the Study Area. It should be noted that larval stages of amphibians and odonates are potentially more vulnerable than adults due to being confined to aquatic habitats.
Table 7.26 Summary of Habitat Requirements, Mobility and Predicted Impacts on Selected Faunal Species of Conservation Interest in the Study Area
|
Species |
Locations Recorded |
Remarks |
Impact Evaluation |
|
Mammals |
|
|
|
|
Melogale moschata (Ferret Badger) |
Possibly recorded from a scat on western ridge of the San Tau Valley. |
Fairly broad habitat tolerance. The species has moderate to high mobility. |
Insignificant impact from construction disturbance. The species is expected to be able to temporarily relocate/ adapt. |
|
Muntiacus reevsii (Barking Deer) |
One visual/ aural observation of the Barking Deer Muntiacus reevsii was made outside the Study Area on 19th May 2002 in tall coastal shrub/ woodland off the coastal path near Hau Hok Wan. |
The Barking Deer typically favour densely vegetated areas (tall shrub and woodland) without human disturbance. |
Insignificant impact from construction disturbance. The species is expected to be able to temporarily relocate/ adapt. |
|
Viverricula indica (Small Indian (seven-banded) Civet) |
Possibly recorded from a scat on western ridge of the San Tau Valley |
Fairly broad habitat tolerance. Moderate to high mobility |
Insignificant impact from construction disturbance. The species is expected to be able to temporarily relocate/ adapt. |
|
Birds |
|
|
|
|
Hieraaetus fasciatus (Bonelli’s Eagle) |
Observed in the broader Tung Chung area (HKBWS pers elen).
|
Bonelli’s Eagles are inhabitants of forest (ibid.) This species is mainly found in lightly wooded hillsides (Carey et al. 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Accipter trivirgatus (Crested Goshawk) |
Observed in the broader Tung Chung area (HKBWS pers elen) and cover all habitats in the area.
|
Crested Goshawks are generally inhabitants of forest (ibid.) |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Saxicola ferrea (Grey Bushcat)
|
Observed within the broader Tung Chung area (HKBWS pers elen). |
They can be found in many types of terrestrial habitats (Carey et al., 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Coturnix japonica (Japanese Quail) |
Observed within the broader Tung Chung area (HKBWS pers elen). |
They can be found in many types of terrestrial habitats (Carey et al., 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Hemixos castanonotus (Chestnut Bulbul) |
Observed within the broader Tung Chung area (HKBWS pers elen). Ngong Ping in plantation and woodland (OAP, 2002). |
Typically found in old forests
|
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Turdus chrysolaus (Brown Thrush) |
Observed at Ngong Ping (OAP, 2002). |
They can be found in many types of terrestrial habitats (Carey et al., 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Cettia fortipes (Mountain Bush Warbler) |
Observed at Ngong Ping (OAP, 2002). |
They can be found in many types of terrestrial habitats (Carey et al., 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (noise) due to the mobility of the species. |
|
Ficedula ugimaki (Mugimaki Flycatcher) |
Observed at Ngong Ping (OAP, 2002). |
They can be found in many types of terrestrial habitats (Carey et al., 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Emberiza tristrami (Tristram’s Bunting)
|
Observed at Ngong Ping (OAP, 2002). |
Can be found in many types of terrestrial habitats (Carey et al., 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Zoothera daunma (Whites’ Thrush) |
Observed in woodland, Ngong Ping (OAP, 2002).
|
White’s Thrush can be found in many types of terrestrial habitats (Carey et al., 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Anthus sylvana (Upland Pitit) |
Observed in grassland habitat |
Have been found to occur mainly in grassy upland habitats (Carey et al. 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Bubo bubo (Eagle Owl) |
Observed in woodland habitat. |
Can be found in many types of terrestrial habitats (Carey et al., 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Accipiter gularis (Japanese Sparrow Hawk) |
Observed in abandoned cultivation (overhead). |
Can be found in many types of terrestrial habitats. |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Ficedula albicilla (Red-throated Flycatcher) |
Observed in woodland. |
Can be found in many types of terrestrial habitats (Carey et al., 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Accipiter virgatus (Besra)
|
Observed in tall shrubland (overhead). |
Can be found in many types of terrestrial habitats (Carey et al., 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Pylloscopus tenellipes (Pale Legged Leaf Warbler) |
Observed in Abandoned cultivation and woodland (overhead).
|
Can be found in many types of terrestrial habitats (Carey et al., 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Haliaeetus leucogaster (White-bellied Sea Eagle) |
Observed grassland above Tower 6 (overhead) |
No suitable nesting areas were observed within the Study Area. |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Reptiles and Amphibians |
|
|
|
|
Megophrys brachykolos (Short-legged Toad) |
Tadpoles were found in seasonal streams at Ngong Ping (OAP, 2002) and SWS feeder stream 4. |
Narrow habitat tolerance. Low to moderate mobility.
|
Potential impacts may result from construction near the Ngong Ping stream and subsequent disturbance (sedimentation and pollutants) without mitigation measures. |
|
Philautus romeri (Romer’s Tree Frog) |
Tadpoles were found in seasonal streams at Ngong Ping SSSI. (OAP, 2002). |
Fairly narrow habitat tolerance. Low to moderate mobility. |
Insignificant impacts are anticipated |
|
Rana exilispinosa (Lesser Spiny Frog) |
Ngong Ping (OAP, 2002).
|
Narrow habitat tolerance. Low to moderate mobility. |
Insignificant impacts are anticipated resulting from construction near the Ngong Ping stream and subsequent disturbance (sedimentation and pollutants). |
|
Rana macrodactyla (Three striped Grass Frog)
|
Grassy banks of Shat Wat Stream (Chan and Lau, 2001). |
Narrow habitat tolerance. Low to moderate mobility. |
Potential impacts may result from construction and subsequent disturbance (sedimentation and pollutants) without mitigation measures. |
|
Rana Livida (Green Cascade Frog) |
Observed in a rocky stream course west of the Ngong Ping Plateau in SWS 2.
|
Stream habitats. Narrow habitat tolerance. Low to moderate mobility. |
Potential impacts may result from construction and subsequent disturbance (sedimentation and pollutants) without mitigation measures. |
|
Chinemys reevesii (Reeves’ Terrapin) |
Observed in stream habitat, Ngong Ping (OAP, 2002).
|
Fairly narrow habitat tolerance. Low to moderate mobility. |
Potential impacts may result from construction near the Ngong Ping stream and subsequent disturbance (sedimentation and pollutants) without mitigation measures. |
|
Elaphe radiata (Copperhead Racer) |
Observed in grassland, Ngong Ping (OAP, 2002).
|
Can be found in many types of terrestrial habitats. |
Insignificant impacts associated with construction. |
|
Achalinus rufescens (Rufous Burrowing Snake) |
Observed in plantation, woodland and shrubland, Ngong Ping (OAP, 2002) |
Can be found in many types of terrestrial habitats. |
Insignificant impacts associated with construction. |
|
Amphiesma stolatum (Buff Striped Keelback) |
Observed in stream habitat, Ngong Ping (OAP, 2002).
|
Can be found in many types of terrestrial habitats. |
Insignificant impacts associated with construction. |
|
Oligodon cinereus (Golden Kuri Snake) |
Observed in grassland, Ngong Ping (OAP, 2002).
|
Can be found in many types of terrestrial habitats. |
Insignificant impacts associated with construction. |
|
Ophiophagus elena (King Cobra) |
Variety of habitats.
|
Can be found in many types of terrestrial habitats. |
Insignificant impacts associated with construction. |
|
Naja atra (Chinese Cobra) |
Variety of habitats.
|
Shrubland, moderate mobility |
Insignificant impacts associated with construction. |
|
Fish |
|
|
|
|
Oryzias curvinotus (Ricefish) |
Lower reaches of both Tung Chung stream and the neighbouring Wong Lung Hang stream to the north (Cheung, 1998 In BMT, 2002). |
Narrow habitat tolerance. Low mobility.
|
No impacts predicted – outside the Study Area. |
|
Insects |
|
|
|
|
Pachliopta aristolochiae (Common Rose, butterfly) |
Ngong Ping en route to Twi Tong Shan to the east of the Study Area (young, 1998; and Young and Reels, 1998). |
Fairly broad habitat tolerance. Moderate to high mobility.
|
No impacts predicted, as habitat will not be disturbed during construction activities. |
|
Troides elena (Birdwing Butterfly) |
Ngong Ping en route to Twi Tong Shan to the east of the Study Area (young, 1998; and Young and Reels, 1998). Woodland and riparian zone Wong Lung Hand Stream (Mott Connell, 2000). Cultivated land at San Tau. |
Moderate to high mobility. |
No impacts predicted, as habitat will not be disturbed during construction activities. |
|
Troides aeacus (Golden Birdwing) |
On path from Ngong Ping to Tung Chung (outside Study Area) (Wong, 1999). |
Moderate to high mobility. |
No impacts predicted, as habitat will not be disturbed during construction activities. |
|
Catochrysops strabo (Forget-me-not) |
Tung Chung area (Bascombe 1993 in Mott Connell Ltd, 2000). |
Moderate to high mobility. |
No impacts predicted, as habitat will not be disturbed during construction activities. |
|
Delias hyparete (Painted Jezebel) |
Tung Chung area (Bascombe 1993 in Mott Connell Ltd, 2000). |
Fairly broad habitat tolerance. Moderate to high mobility. |
No impacts predicted, as habitat will not be disturbed during construction activities. |
|
Potanthus trachala (Lesser Band Dart) |
Tung Chung area (Bascombe 1993 in Mott Connell Ltd, 2000). |
Fairly broad habitat tolerance. Moderate to high mobility. |
No impacts predicted, as habitat will not be disturbed during construction activities. |
|
Lamproptera curius (Dragontail) |
Near mangrove habitat near the confluence of San Tau Stream with Tung Chung Bay. |
Moderate to high mobility. |
No impacts predicted as mangrove habitat will not be disturbed during construction activities. |
Note: *All wild birds are Protected in Hong Kong, Class 2 Protected Animal of PRC and Appendix II of CITES
The Material Ropeway method for construction is considered to have a greater impact (including the scenario where mitigation measures are implemented) on the ecology of the Study Area than the Helicopter Construction method.
In general the Material Ropeway construction method has greater disturbance (and more significant impacts) resulting from:
· habitat loss to a range of habitat types (in particular woodland and tall shrub);
· additional impacts on water quality and sedimentation and subsequent impact on streams;
· trampling of flora species.
Material Ropeway construction method is anticipated to have more significant impacts on the ecology of the Study Area and will have greater temporary impacts on fauna than that of the Helicopter (only) construction method and is not recommended.
A summary of construction phase unmitigated impacts arising from the Project are given in Table 7.27 below.
Table 7.27 Summary of Construction Phase Impacts
|
General Impact |
Specific Impact |
Severity |
Mitigation Required |
|
Habitat Loss |
Habitat loss from clearing of grassland and shrubland and secondary woodland etc (approximately 1.7ha in total).
|
Moderate |
Yes |
|
|
Flora of conservation interest including the Bamboo Orchids and Camellia sinensis.
|
Minor |
Yes |
|
|
Construction near the Ngong Ping at Ngong Ping and construction of the Emergency Rescue Trail and potential disturbance to cause sedimentation, pollution and riparian clearing etc impacting on species of conservation interest including: · Three striped Grass Frog Rana macrodactyla Shat Wat Stream · Green Cascade Frog Rana Livida west of the Ngong Ping Plateau in SWS 2.
|
Moderate |
Yes |
|
|
Removal of woodland and tall shrubland impacting on mammals, avifauna and insects of conservation interest.
|
Minor |
Yes |
|
|
Reduction of nectar sources for butterflies.
|
Insignificant |
No |
|
Habitat Fragmentation |
Fragmentation of habitats from the construction of the Emergency Rescue Trail.
|
Insignificant. |
No. |
|
|
Habitat removal and stream modification works at Ngong Ping Terminal and impact of amphibian species described above.
|
Minor |
Yes |
|
Disturbance
|
Disturbance to butterfly species of conservation interest
|
Insignificant |
None |
|
|
Disturbance to mammal and reptile species of conservation interest.
|
Minor |
Yes |
|
|
Disturbance (noise, increased human activity) to birds and impact on species of conservation interest. |
Insignificant |
No |
Operational phase impacts are associated with operational activity result generally result from disturbance (e.g. the noise of cable cars and increased human activity during maintenance). These potential impacts are discussed further in the sections below.
Disturbance is an unavoidable impact of the operation process. Disturbance will generally have insignificant impacts on mobile taxa, or taxa which do not have highly specific habitat requirements, such as birds, large mammals, most reptiles, and butterfly and dragonfly adults, and in these cases disturbance impacts will be avoided by ensuring operational activities are undertaken according to Environmental Code of Practice and the proposed mitigation measures.
Disturbance impacts incurred during the operational phase are associated with elevated noise levels, presence of cable car and overall higher contact with associated human activities. Noise levels associated with the operation of the cable car rather than visual impacts (perceived threats from moving cable cars) are considered to be the main cause of impact to wildlife species.
The operational noise is not considered to be a significant impact to flora and fauna (the operational noise is discussed in Section 4).
The operation pollution impacts from linear developments (but in particular road developments) can affect the abundance of insect prey available to birds. However, it is unlikely that air pollution impacts on flora and fauna will result from the operation of the cable car.
In the operation phase providing that the exposed surfaces are allowed to regenerate (or revegetated). Minor to moderate water quality impacts are anticipated to result from the operation of the cable car. However mitigation measures should ensure that impacts on Stream habitats do not occur.
The effects of linear developments such as roads that form barriers to wildlife populations are well documented (English Nature, 1994; Treweek, 1999). Many animals are reluctant to cross structures such as roads and they can act as an effective barrier preventing migration between adjacent habitats.
The narrow width of the path reduces the impact of the emergency rescue trail. However, in steep sections (where a retaining wall is used) mammal species may find the trail a physical barrier for movement. Also, the cable car may effectively operate as a barrier due to noise and visual impacts that induce deliberate avoidance of the area (thereby cutting off the access to habitats on the other side of the alignment.
The emergency rescue trail is narrow and the impacted of ‘exposed areas’ will generally not impact on fauna species. It is possible that some cryptic species (e.g. Short-legged Toad) avoid the trail as a consequence. The trail is unlikely to act as a barrier to movement of such species between areas of suitable habitat bisected (and or fragmented by the trail). This impact is considered to be insignificant.
The Emergency Rescue Trail will not create a barrier effect for freshwater fish, providing that no channels/culverts are constructed at points where the trail crosses watercourses.
The construction of the Emergency Rescue Trail may require a retaining wall (preventing the free movement of some species). Also the trail has the potential to have barrier effects in densely vegetated areas (i.e. tall shrub and woodland habitats).
It is anticipated that the trail would be relatively narrow and constructed of ‘natural’ materials leaving only a negligible distance between habitat areas. It is anticipated that the movement of ground dwelling species will not be affected. The nature of the cable car design (relatively small clearing requirements at tower and angle station locations and the emergency rescue trail), it is anticipated that the cable car would have minor impact on fauna species and their movement between habitats.
There is a large volume of literature on bird collisions with man-made structures reported to cause bird kills include telecommunication or radio transmission towers; power transmission and distribution lines. The causes of bird collisions with man-made structures are considered to be:
· invisibility (i.e. power lines at night);
· deception (caused by glazing in buildings); and
· confusion (caused by light refracted or mist).
Towers, cables and powerlines have the potential to cause bird collisions and electrocution (Andersen-Harild and Bloch 1973, Cochrane et al. 1991 in Ove Arup & Partners Hong Kong Ltd, 2002). Birds either fly directly into towers or cables (mainly at night when lines are invisible), or are electrocuted when wingtips contact power lines simultaneously upon landing or from taking flight.
The Study Area is not a known path for migratory species or a significant breeding or feeding area for migratory species, although the coastal mudflat and mangrove habitats of Tung Chung Bay supports quite a diverse range of birds. A flock of 26 individuals of Little Egret Egretta garzetta recorded and two Chinese Pond Heron Ardeola bacchus and two Reef Egret Egretta sacra were recorded. Other migratory species in the area are the Palelegged Leaf Warbler P. tenellipes, Red-throated Flycatcher Ficedula albicilla and Brown Flycatcher Muscicapa latirostris.
Bird kills are typically reported on cloudy, overcast or foggy nights when visibility is low (Merriam 1885, Culver 1915, Brooks 1951, Bagg 1965 in Ove Arup & Partners Hong Kong Ltd, 2002). Although bird collisions also occur on clear nights (Tufts 1928, Chamberlain 1961, Anon. 1975 in Ove Arup & Partners Hong Kong Ltd, 2002), birds normally avoid obstacles in clear skies (Avery et al. 1975, Avery 1976 in Ove Arup & Partners Hong Kong Ltd, 2002).
Bird collisions are not considered a potential significant impact, as no evidence is present that the area is a migratory bird flight path or an area situated close to breeding or feeding colonies of migratory birds. Although no impact is expected the project will it adopt a precautionary approach and recommend mitigation measures to avoid impacts to bird species.
A number of raptors are considered to occur in the Study Area including: Eagle Owl Bubo bubo, Besra Accipiter virgatus, Bonelli’s Eagle Hieraaetus fasciatus, Crested Goshawk Accipiter trivirgatus and Japanese Sparrow Hawk A. gularis. Besra, Bonelli’s Eagle, Crested Goshawk and Japanese Sparrow Hawk. The impact of electrocution of raptors is considered to be the main cause of mortalities of Bonelli’s Eagle Hieraaetus fasciatus in Europe (Manosa and Real 2001 In Ove Arup & Partners Hong Kong Ltd, 2002). The cables of the Cable Car System will not be electrified and no mortalities are anticipated.
It is anticipated that non-migratory species will not to be impacted upon. They will have familiarly with the Cable Car System (once operating) and will have a lower potential to collide with the cableway or towers.
No bird species mortality has been reported from the collision of bird species into structures from the construction or operation of the Ocean Park Cable Car System or transmission lines in general in Hong Kong.
Birds of prey may be beneficially impacted upon by the provision of perching and nesting sites, which has been known to potentially:
· extend the breeding range of certain species;
· increase local densities of populations, and
· open up new foraging habitat for species that hunt from perches.
It is possible that the towers could be used for nesting and it is not anticipated that the birds will have any impacts on the Cable Car System. It is suggested that investigation into the provision of “nesting boxes” above each Tower should be undertaken.
Clearing can also affect raptors (beneficially or adversely depending on the species) by altering the distribution and availability of prey populations. The factors contributing to these are complex and not readily predicted. It is unlikely that the clearing for the Project is sufficient to have any impact.
People visiting Ngong Ping are likely to increase several fold which may lead to increased disturbance to wildlife and vegetation. The extent of the impacts will depend on the carrying capacity of the area used and on visitor management.
Impacts as a result of increased visitor usage of the area are likely to be very difficult to quantify. The use of the cable car and the Country Park by visitors could result in increased litter and waste and impacts from trampling of grass and shrub species in the Country Park (including taking of Orchid flowers etc), although it is considered unlikely that large numbers of visitors will venture into the Country Park.
No systematic observations on firebreak effectiveness have been made in Hong Kong (Porcupine, 2002). Also, the clearing of more dense vegetation (such as tall shrub and woodland) may assist in the spread of fire, as grassland habitats are the most frequently burnt habitats in Hong Kong (Lawrence, 1994), which is supported by visual observations of previous hill fires in the Study Area during field investigations. Ecological impacts from the construction and operation of a 30m wide firebreak will result in significant and unacceptable impacts that cannot be mitigated. However, a 30m wide firebreak is not required for the Project. The increase in the occurrence of fire as a result of the Project is unlikely but has been taken into consideration in the impact mitigation as precautionary measures.
A summary of operation phase unmitigated impacts are provided in Table 7.28 below.
Table 7.28 Summary of Operation Phase Impacts
|
General Impact
|
Specific Impact |
Severity |
Mitigation Required |
|
Disturbance
|
Disturbance from the noise and movement of the Cable Car includes associated noise impacts and pollution emissions, particularly the potential impact on water quality from sedimentation and erosion.
|
Insignificant |
No. |
|
Barrier effects
|
Effect of the construction of the Emergency Rescue Trail and the subsequent impact on ground dwelling species.
|
Insignificant. |
No. |
|
Bird mortality due to impact with structures |
Mortality incurred by avifauna as a consequence of collisions with Cable Cars.
|
Insignificant. |
No. |
|
Birds nesting on towers |
Beneficial impact on birds from the provision of perching and nesting sites
|
Insignificant. |
No. |
|
Increased number of visitors |
Increased litter and waste and impacts from trampling of grass and shrub species in the Country Park (including taking of Orchid flowers etc).
|
Minor. |
Yes. |
|
Hill fires |
No impact.
|
Insignificant. |
No. |
A number of projects have been proposed on Lantau Island although only the proposed Ngong Ping Sewage Treatment Works is within close vicinity to the Project. Other projects that are proposed on Lantau but are not in the vicinity (and will not have any cumulative impacts) in associated with the cable Car System are:
· improvement to Tung Chung Road between Lung Tseng Tau and Cheung Sha;
· 132 KV Supply Circuit from Pui O via Chi Ma Wan Peninsula via Sea Crossing towards Cheung Chau; and
· construction of an international theme park in Penny's Bay of North Lantau.
The Ngong Ping Sewage Treatment Works is located within the Study Area. However, it will not contribute to the cumulative ecological impacts as limited clearing requirements are anticipated for the Project. Potentially, both Projects will contribute to the improved health of the stream at Ngong Ping.
In accordance with the guidelines in the TMEIA on ecology impact assessment the general policy for mitigating impacts to ecological resources, in order of priority, are:
· Avoidance: Potential impacts should be avoided to the maximum extent practicable by adopting suitable alternatives;
· Minimization: Unavoidable impacts should be minimized by taking appropriate and practicable measures such as constraints on intensity of works operations (e.g. dredging rates) or timing of works operations; and
· Compensation: The loss of important species and habitats may be provided for elsewhere as compensation. Enhancement and other conservation measures should always be considered whenever possible.
Accidental or other intrusion of construction activities beyond the designated works area can also be avoided. The works area boundary should be defined throughout using lightweight but weather-resistant material, such as a low shade-cloth barrier. No activities, including casual disturbance, vehicle parking and temporary storage should be tolerated outside the defined boundary.
As discussed in the previous section, no major ecological impacts are anticipated. However, a precautionary approach should be adopted. In general most flora and fauna species will not require mitigation due to their low ecological value and commonness in Hong Kong. Mitigation measures according to the Water Quality, Noise and Air Quality Sections will militate against disturbance to flora and fauna species.
Revegetate areas of temporary vegetation loss particularly woodland habitat and tall shrubland habitat resulting from the removal of habitat for the emergency rescue trail, which cannot be avoided for safety reasons (2 hectares as shown in Figure 7.5). Species used for planting should be undertaken in consultation with AFCD and take reference from the species identified in the Tree Survey and be native to Hong Kong or South China region (if possible).
Reconstruct and revegetate the stream at Ngong Ping (refer to Figure 5.3), taking account of improved water quality in future. The restitution of the stream should take into consideration the potential presence (downstream) of protected and rare amphibian species. Riparian vegetation should also be planted and maintained. Consultation with relevant community groups and relevant government departments would ensure that the stream restitution is effective. Water should not be soured from any watercourses on site.
The provision of water filled pots for amphibian species is not presented as an option due to the potential spread of dengue fever. However the clearing of riparian vegetation should be avoided where possible along the Emergency Rescue Trail.
Protected and rare flora species including orchids and Camellia species will be maintained and fenced off from construction work to prevent any accidental damage. If any impacts are evident on rare or protected species the affected flora species shall be transplanted to a similar environment as the original habitat (i.e. in the same habitat type in the local vicinity). All the individuals of the species should be relocated. It is recommended that seeds of the target species be collected to preserve the genetic resource and allow more source plants to be transplanted in case of the failure of transplantation. The seeds should be collected and preserved or germinated appropriately by a qualified botanist.
Vegetation (that is considered to harbour sensitive habitat or of biological significance should be clearly marked by a qualified person for protection (to prevent accidental damage during construction). This person should be present during tree clearing.
During construction, a suitably trained person shall be present to relocate any terrestrial fauna located in the construction area (including those that are rare or protected). If any additional species listed as rare or protected are confirmed present, additional field surveys specific for the listed species should be conducted before the resumption of construction.
Noise resulting from the preparation for construction shall remove most faunal presence from the vicinity until construction has ceased, however it is recommended that a tap/ knock of trees prior to clearing should be undertaken to reduce the chance of faunal injury. If any fauna species are injured during construction, the species should be promptly treated by the nearest fauna carer or vet.
Where topsoil and vegetation is stripped during construction, wherever possible, topsoil and vegetative matter will be stockpiled. Stockpiled material will be stabilised to prevent sediment generation and re-spread as part of landscaping and rehabilitation of disturbed areas following construction. Exposed soil shall be covered or the run-off diverted away from stream habitats if possible. Temporary silt traps or sedimentation pools should be considered.
Cleared vegetation to be ‘chipped’ (where appropriate) and stored for use as mulch during site landscaping works and/or in surrounded vegetated areas susceptible to erosion.
Some of the locations are located in areas with vegetation. The contractor is not allowed to fell any trees or form any open access roads in any area or remove any vegetation without prior approval from the “Environmental Team”.
Only one pathway no wider than 1.5m shall be established to reach all of the tower locations within the Country Park (prior approval from Country and Marine Parks Authority is required). No additional paths shall be made.
Flags shall be placed indicating the lateral extent of the pathway. Flags shall be placed accordingly so those workers can easily distinguish the next set of pathway flags. A different set of coloured flags shall be used to define the work site at the tower locations. Workers shall not move any flags and shall notify the engineer if any maintenance is needed on the pathway or to the flags themselves.
Access to work sites to be restricted and signed to prohibit unauthorised entry and the construction area should be fenced. This will minimise disturbance to vegetation, including unauthorised clearing. There shall be no work outside of the designated sites.
Restrict the passage of machinery outside the designated construction areas and a minimum number of machinery parking areas should be used and clearly designated.
Workers shall not disturb birds and other animals. Animals shall not be fed and no food shall be left for any animals and no pets of any type shall be allowed on any site.
Prior to works commencing on site, a complete photographic record shall be obtained of the site, its surroundings, any watercourses and any dams or pipes constructed by others.
A photographic survey shall also be made of the site upon completion of all works. Following review of the photographic record, additional measures may be needed to make the site look natural.
Reinstate temporary work sites/disturbed areas to its original condition immediately after completion of construction.
Workers shall not leave any litter on site. Litter shall not be burned on site but shall be removed off site. All surplus construction materials brought onto site shall be removed from site and daily clearance of general litter shall be undertaken. Particular care shall be taken with bottles, wire, polystyrene lunch boxes, plastic wrapping, cans and non-degradable materials. Waste from portable toilets will be taken off-site.
Watercourses shall not be polluted with soaps, detergents or excretion.
MTRC’s Contractor shall propose a Fire Prevention Strategy in the Method Statement to the approval of the Engineer for all works within the Country Park. The strategy will be developed prior to operation in conjunction with relevant Government authorities. This strategy will aim to protect sensitive plant communities within the site and it will also consider the needs of significant fauna species.
The Fire Prevention Strategy will include measures to prevent hill fires including no smoking; cooking or use of open fires on any site; no cigarette lighters or matches shall be carried onto the site in connection with the Tung Chung Cable Car Project. Welding or hot work is also not permitted and temporary fire fighting equipment shall be provided in all work areas.
No vehicles shall be allowed on site without written permission from the Country and Marine Parks Authority.
There shall be regular cleaning and frequent watering of the construction sites during dry periods to avoid dust (as determined by the engineer), but attention should be paid to prevent washing waste materials off site.
No fuel or oil shall be stored within the Country Park and no pesticides or herbicides will be used within the Country Park.
Watercourses within and adjacent to the working areas shall be treated with extreme care. They shall not be used as repositories for waste materials. Extreme care shall be exercised during the transportation, handling and storage of potential pollutants and in the operation of mechanised equipment to avoid spillage.
MTRC’s contractor shall propose an Emergency Spillage Plan in the Method Statement to the approval of the Engineer for all works within the Country Park.
The contractor shall provide for all necessary materials on site for emergency spill measures and shall be trained in emergency spill response.
Details of drilling fluid additives confirming that they will not contaminate the water gathering grounds shall be deposited.
Table 7.29 Summary of Impacts and Mitigation Measures
|
General Impact |
Specific Impact |
Severity |
Mitigation Required |
|
Construction |
|
|
|
|
Habitat Loss |
Habitat loss from clearing of grassland and shrubland and secondary woodland etc (approximately 1.7ha in total).
|
Moderate |
Ensure that clearing is kept to a minimum.
Ensure that areas of temporary vegetation loss are revegetated with suitable species and that suitable landscaping is provided.
Compensatory planting of 2ha of tall shrubland and woodland to fully compensate for loss of all habitat types. The approximate location is shown in Figure 7.5.
Construction practices outlined in the Nature Conservation Policy are adhered to.
|
|
|
Flora of conservation interest including the Bamboo Orchids and Camellia sinensis.
|
Minor |
Fencing, translocation by experienced Botanist if required
Construction practices outlined in 7.11.1.
|
|
|
Construction near the Ngong Ping at Ngong Ping and construction of the Emergency Rescue Trail and potential disturbance to cause sedimentation, pollution and riparian clearing etc impacting on species of conservation interest including: · Three striped Grass Frog Rana macrodactyla Shat Wat Stream · Green Cascade Frog Rana Livida west of the Ngong Ping Plateau in SWS 2.
|
Moderate |
Reconstruct and revegetate the stream at Ngong Ping with consultation with relevant Government Departments and community groups.
Restriction of working hours.
Construction practices outlined in 7.11.1.
No vehicle or machine should be maintained or refuelled within 50m of a watercourse. |
|
|
Removal of woodland and tall shrubland impacting on mammals, avifauna and insects of conservation interest.
|
Minor |
’As above’ |
|
|
Reduction of nectar sources for butterflies.
|
Insignificant |
None |
|
|
|
|
|
|
Habitat Fragmentation
|
Fragmentation of habitats from the construction of the Emergency Rescue Trail.
|
Insignificant |
None |
|
|
Habitat removal and stream modification works at Ngong Ping Terminal and impact of amphibian species described above. |
Minor |
Reconstruct and revegetate the stream at Ngong Ping.
Construction practices outlined in 7.11.1.
Exposed areas should be revegetated as soon as possible.
Stockpiles of soil should be covered.
|
|
Disturbance
|
Disturbance to butterfly species of conservation interest
|
Insignificant |
None |
|
|
Disturbance to mammal and reptile species of conservation interest |
Minor |
Restriction of working hours.
Construction practices outlined in 7.11.1.
|
|
|
Disturbance (noise, increased human activity) to birds and impact on species of conservation interest. |
Insignificant |
Restriction of working hours.
Construction practices outlined in 7.11.1.
|
|
Operation |
|
|
|
|
Disturbance
|
Disturbance from the noise and movement of the Cable Car includes associated noise impacts and pollution emissions, particularly the potential impact on water quality from sedimentation and erosion.
|
Insignificant |
None |
|
Barrier effects
|
Effect of the construction of the Emergency Rescue Trail and the subsequent impact on ground dwelling species.
|
Insignificant |
Ensure that exposed areas are revegetated. Woodchips from cleared vegetation should be used where appropriate to prevent erosion. |
|
Bird mortality due to impact with structures |
Mortality incurred by avifauna as a consequence of collisions with Cable Cars.
|
Insignificant |
None |
|
Increased number of visitors |
Increased litter and waste and impacts from trampling of grass and shrub species in the Country Park (including taking of Orchid flowers etc). |
Minor |
Provision of bins and signage of the value of the local environment
Monitoring/ clean up of the Emergency Rescue Trail by Cable Car Staff.
|
|
Hill fires |
No impact.
|
Insignificant |
None. |
The proposed mitigation measures are generally considered adequate to mitigate all of the identified impacts in the short term, as discussed below.
Table 7.30 Summary of Proposed Mitigation Measures and Predicted Residual Impacts
|
Potential Impact |
Proposed Mitigation Measures |
Predicted residual Impact |
|||
|
Avoidance |
Minimizing |
Compensation |
|||
|
On-site |
Off-site |
||||
|
Habitat loss including woodland and tall shrub habitat loss |
The majority of woodland and tall shrub habitat has been avoided by alignment.
Habitats cannot be further avoided. |
Restoration of disturbed areas in accordance with this section and the LVIA section.
|
Intensive planting of native shrub/ tree species at tower locations, Emergency Rescue Trail and surrounding the terminal locations.
Planting of 2ha of woodland habitat.
|
No off site compensation required.
|
No significant residual impacts providing that compensation planting is undertaken. |
|
Significant flora species |
- |
Transplantation to appropriate nearby location. |
Re-planting at appropriate nearby location. |
No off site compensation required.
|
No residual impacts on species of conservation interest. |
The EM&A for ecology is detailed in Section 12 Environmental Monitoring and Audit and in the Environmental Monitoring and Audit Manual.
The Study Area traverses a large area of Country Park and contains a variety of habitats, of which the most ecologically valuable are streams, secondary woodland, and tall shrub habitat. The Study Area is also floristically diverse and supports numerous faunal species of moderate and high conservation interest, many of which have a narrow habitat tolerance and are sensitive to disturbance. Overall, the Study Area is assessed to be of medium to high ecological value.
The proposed cable car alignment and tower locations have relatively small clearing requirements compared other linear developments such as roads and pipelines (as well as the other cable cars systems considered).
The species of conservation interest recorded along the alignment were generally observed in other locations in the broader survey area (Figure 7.2). The species of conservation interest appear to be widely distributed in the wider survey area and do not appear confined to any single location. The exception to this is amphibians that have relative low mobilities and may be impacted upon by sedimentation and contamination. Although the stream at Ngong Ping appears to have poor water quality, particular care in the design and construction of the Ngong Ping Terminal is necessary.
Construction of the proposed Project must be conducted in an appropriately ecologically sensitive manner, with particular attention given to avoidance or minimisation of disturbance through appropriate works scheduling and responsible works area maintenance. Many streams and forest habitats in the Study Area are of particularly high ecological value due to a low level of anthropogenic disturbance, and it is crucial that impacts to these highly sensitive habitats are avoided or minimised wherever possible. The loss of ecologically valuable habitat should be mitigated to the fullest possible extent.
Based upon this, in addition to the measures integrated into the design of the cable car infrastructure such as reduction of the tower and Angle Station footprint as far as possible to minimise habitat loss and a comprehensive drainage system to avoid and minimise impacts on the stream courses, a series of ecological mitigation measures have been proposed to reduce impacts to acceptable levels.
The effectiveness of impact mitigation measures will need to be assessed by the proposed environmental monitoring and audit programme. As discussed above, some residual ecological impacts will occur but these are considered to be acceptable within the overall framework of the scheme.
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