This section presents the ecological baseline information
for terrestrial ecological resources (particularly avifauna) gathered from the
literature review and focussed vessel-based surveys, which covered a period of 9
months of both wet and dry seasons (covering February to October) to establish
the avifaunal baseline ecological conditions of the proposed Wind Farm
Development Site (hereafter called Project Site) in southwestern waters of Lamma Island in Hong Kong.
This section also presents the results of an
assessment of the ecological importance of the avifauna resources of the Study
Area in southwestern waters of
8.2
Legislative
Requirements and Evaluation Criteria
Relevant legislative requirements and evaluation
criteria for the protection of species and habitats of terrestrial ecological
importance are as follows:
1.
Wild Animals Protection Ordinance (Cap
170);
2.
Protection of Endangered Species
of Animals and Plants Ordinance (Cap 586);
3.
The Technical Memorandum on Environmental
Impact Assessment Process under the Environmental Impact Assessment Ordinance
(EIAO-TM);
4.
United Nations Convention on Biodiversity
(1992); and,
5.
PRC Regulations and Guidelines.
8.2.1
Wild Animals Protection Ordinance (WAPO)
(Cap 170)
Under the Wild
Animals Protection Ordinance (WAPO) (Cap 170), designated wild animals are
protected from being hunted, whilst their nests and eggs are protected from
destruction and removal. All birds
and most mammals, including all cetaceans, are protected under this Ordinance,
as well as certain reptiles, amphibians and invertebrates. The Second
Schedule of the Ordinance that lists all the animals protected was last
revised in June 1997.
8.2.2
Protection of Endangered
Species of Animals and Plants Ordinance (Cap 586)
The Protection of Endangered Species of
Animals and Plants Ordinance (Cap 586) was enacted to align
8.2.3
The Technical Memorandum on
Environmental Impact Assessment Process under the Environmental Impact
Assessment Ordinance
Annex 16 of the EIAO-TM
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 recommends the criteria that can be used for evaluating ecological
impacts.
8.2.4
United Nations Convention on
Biological Diversity
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 SAR has stated that it will be
“committed to meeting the environmental objectives” of the Convention
(Planning, Environment and Lands Branch 1996).
8.2.5
PRC Regulations and Guidelines
In 1988 the PRC ratified the Wild Animal Protection Law, which lays down basic principles for
protecting wild animals. The Law prohibits
killing of protected 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.
The proposed wind farm development site is located approximately
2 km away from the nearest shoreline at southwestern
It should be noted that the works areas for
land-based works including the transmission cable landing and onshore cable
installation are not included in the Study Area. All land-based construction works will
be undertaken at the Lamma Power Station Extension
which has been a restricted area and managed by the Hong Kong Electric Co. Ltd.
since the commencement of operation in 2006 ([1]).
The site is reclaimed land that is urbanised and subject to a high
degree of disturbance related to existing quay and Power Station
activities. The terrestrial ecological
resources (vegetation, terrestrial habitats and wildlife) within the Lamma Power Station Extension are expected to be very
limited and are considered of minimal ecological concern. Impact assessment of the land-based
construction on terrestrial habitats and wildlife resources at the Lamma Power Station Extension is therefore considered not
required and is not discussed further in this section of the EIA.
8.4
Literature Review
of Avifauna
8.4.1
Methodology
A preliminary desktop study and literature review has
been conducted to determine the existing conditions of avifauna in particular
migratory seabird within the Study Area.
The literature review included a review of the following:
·
Hong
Kong Biodiversity (Agriculture, Fisheries and Conservation Department Newsletters)
([2]);
·
Annual
Report of the
·
The
Avifauna of
·
Pilot
Project to Increase Awareness of the Ecological Importance of the Breeding
Colonies of Terns in
·
Seabird
Migration Survey in Southern and South-eastern
·
Renewable
Energy by a Wind Turbine System on
·
Helipad
at Yung Shue Wan,
·
A
Commercial Scale Wind Turbine Pilot Demonstration at Hei
Ling Chau –EIA Study ([9]); and,
·
8.4.2
Results
Species Occurrence
Results from
the baseline surveys, conducted previously as part of various EIA studies at or
around
Table 8.1 Species
of Conservation Interested Recorded in and around
|
Species |
Commonness in |
PRC Protection Status |
|
CITES Appendix |
|
Pacific
Reef Egret |
Uncommon
but localised |
II |
Rare |
II |
|
Black-eared
Kite |
Widespread
and common |
II |
|
II |
|
Common
Buzzard |
Widespread
and common |
II |
|
II |
|
Crested
Goshawk |
Uncommon
but localised |
II |
Rare |
II |
|
Uncommon
but localised |
II |
|
II |
|
|
White-bellied
Sea Eagle |
Uncommon
but localised |
II |
Indeterminate |
II |
|
Common
Kestrel |
Widespread
and common |
II |
|
II |
|
Greater
Coucal |
Widespread
and common |
II |
Vulnerable |
|
|
Lesser
Coucal |
Widespread
and common |
II |
Vulnerable |
|
|
Emerald
Dove |
Scarce
but widespread |
|
Vulnerable |
|
It has also
been suggested that Bonelli's Eagle Hieraaetus fasciatus is present in Lamma ([11]) but sighting records have not been reported in recent years. The eagle is listed as rare species in the
China Red Data Book, Class II
protected species in PRC and CITES Appendix II.
Migratory Seabird Population
It has been documented that approximately 38 species
of seabirds have been recorded in
A total of 8,750 individuals in 23 of these recorded
seabird species were recorded during the migratory spring season (March to May)
in 2006 in southern and south-eastern Hong Kong waters, including Lamma Island (Table
8.2) ([14]).
Red-necked Phalaropes Phalaropus lobatus were the largest group of seabirds observed
during the survey (~75% of total numbers).
Other key species recorded included White-winged Tern Chlidonias
leucoptera,
Black-naped Tern Sterna sumatrana,
Aleutian Tern Sterna aleutica and Greater Crested Tern Sterna bergii.
Spatial variation in bird sightings record was also found in which more
terns occurred in the southern waters (i.e. area between Po Toi
and Lamma Island), while more Red-necked Phalaropes
occurred in the south-eastern waters (i.e. area near the Ninepins) (Figure
8.2).
Table 8.2 Total
Number of Seabirds Recorded during HKBWS Surveys (Total of 22 surveys days
during March to May 2006) and its Percentage
Contribution ([15])
|
Seabirds |
Number (% of Total) |
|
Family
Scolopacidae (Sandpipers) |
|
|
Red-necked
Phalarope Phalaropus lobatus |
6,618 (75.63) |
|
Sub-total |
6,618 (75.63) |
|
Family
Sternidae (Terns) |
|
|
Whiskered
Tern Chlidonias hybridus |
6 (0.07) |
|
White-winged
Tern Chlidonias leucopterus |
754 (8.61) |
|
Aleutian
Tern Sterna aleutica |
200 (2.28) |
|
Bridled
Tern Sterna anaethetus |
55 (0.63) |
|
Gull-billed
Tern Sterna nilotica |
5 (0.06) |
|
Caspian
Tern Sterna caspia |
4 (0.05) |
|
Common
Tern Sterna hirundo |
212 (2.42) |
|
Roseate
Tern Sterna dougallii |
2 (0.02) |
|
Black-naped Tern Sterna sumatrana |
258 (2.95) |
|
Sooty
Tern Sterna fuscata |
1 (0.01) |
|
Little
Tern Sterna albifrons |
1 (0.01) |
|
Greater
Crested Tern Sterna bergii |
10 (0.11) |
|
Unidentified
Tern Chlidonias sp. / Sterna sp. |
219 (2.50) |
|
Sub-total |
1,727 (19.73) |
|
Family
Laridae (Gulls) |
|
|
Yellow-legged
Gull Larus cachinnans |
2 (0.02) |
|
Black-tailed
Gull Larus crassirostris |
2 (0.02) |
|
Heuglin’s Gull Larus
heuglini |
158 (1.81) |
|
Slaty-backed Gull Larus
schistisagus |
1 (0.01) |
|
Unidentified
Gull Larus sp. |
8 (0.09) |
|
Sub-total |
171 (1.95) |
|
Family
Stercorariidae (Jaegers and Skua) |
|
|
Long-tailed
Jaeger Stercorarius longicaudus |
113 (1.29) |
|
Parasitic Jaeger Stercorarius parasiticus |
13 (0.15) |
|
Pomarine Jaeger/Skua Stercorarius pomarinus |
17 (0.19) |
|
Unidentified
Jaeger Stercorarius sp. |
18 (0.21) |
|
Sub-total |
161 (1.84) |
|
Family
Procellariidae (Shearwaters) |
|
|
Streaked
Shearwater Calonectris leucomelas |
52 (0.59) |
|
Short-tailed
Shearwater Puffinus tenuirostris |
15 (0.17) |
|
Unidentified
Shearwater Puffinus sp. |
3 (0.03) |
|
Sub-total |
70 (0.80) |
|
Family
Alcidae (Auks) |
|
|
Ancient Murrelet Synthliboramphus antiquus |
3 (0.03) |
|
Sub-total |
3 (0.03) |
|
Grand Total |
8,750 (100) |
As part of the EIA Study for another proposed wind farm
development project in the eastern waters in Hong Kong, focussed surveys were
conducted from May 2006 to August 2006, from December 2006 to May 2007, and
August 2007 to December 2007 ([16]).
The surveyed area was located at least 30 km northeast from the Project
site. A total of 57 bird species
and six unidentified species were recorded over 59 survey days. Nine species were considered to be of
relatively higher sensitivity due to their conservation significance,
distribution and/ or abundance within their Study Area, including
Breeding Tern Population
The
breeding bird survey conducted by Hong Kong Bird Watch Society (HKBWS) have recorded
three breeding bird species within
Table 8.3 Breeding
Tern Species Recorded in Hong Kong by Carey et al (2001) ([18])
|
Common Name |
Species Name |
HK Status |
Commonness in |
|
Gulls & Terns |
|||
|
Roseate Tern |
Sterna dougallii |
SV |
·
Uncommon but localised in |
|
Black-naped Tern |
Sterna sumatrana |
SV |
·
Common in |
|
Bridled Tern |
Sterna anaethetus |
SV |
·
Uncommon but localised in |
Figure
8.3 shows the
distribution of the recorded breeding tern colonies in
Distribution of White-bellied Sea Eagle
(WBSE)
WBSEs
are also known to have nesting colonies in
8.5
Identification of
Information Gap
The literature review discussed in the above section
revealed that baseline information of migratory birds/seabird is available but
not specific to the Study Area or the Project Site.
To supplement and update the available baseline
information, vessel-based
avifauna surveys were undertaken three days per month from July 2008 to June
2009 for 9 months (excluding November 2008 to January 2009) covering both wet
and dry seasons around
8.6
Ecological
Baseline Surveys
8.6.1
Methodology
Nine months of avifauna vessel surveys (as required
in the Study Brief) were conducted
using the quantitative line transect method. Vessel-based surveys were undertaken
three times per month from July to October 2008 and from February to June 2009
at the selected transect lines which were the same as the marine mammal survey
transects which are standardised in
·
Spring
(March to May) – Migratory Season
·
Summer
(June to August) – Breeding Season
·
Autumn
(September to November) – Migratory Season
·
Winter
(December to February)
During each survey, the vessel transited the transect
lines at a relatively constant speed of 13-15 km/hr, observations were made
using 8x binoculars and all birds seen within 1 km both sides along the
transect lines were counted and identified to species where possible. Detailed information on bird species,
sex and age where feasible, abundance, observed coordinates, bird
activities/behaviour, flying height and path were recorded during the survey. Activities/behaviour of the birds were
categorised into five classes:
·
Flying
- Birds moving in the air following a particular direction without conducting
any of the other activities as below.
·
Soaring
- Birds moving in the air usually making a form of circular movement.
·
Resting
– Birds do not move, remain in the same location in certain period of time (eg Birds of Prey perching on trees, Egrets standing on
rock, Tern standing on floating objects).
·
Foraging/Feeding
- Birds seen attacking, collecting, pecking or carrying food with their bill or
feet could be defined as foraging or feeding.
·
Swimming
– Birds making movements on a water surface or floating on the sea.
Surveys were conducted during daylight hours only and
night survey was not undertaken.
Although night surveys are considered to be useful to track nocturnal
migrants, in an open sea environment, surveys can only be done by radar
tracking system as seabirds seldom make calls (as in owls). However, such a system cannot collect
detailed information on birds such as species identify and abundance. It is considered the current survey
findings sufficient to determine the ecological significance of the Study
Area.
Quantitative Grid Analysis
Raw sightings records plotted on maps are
generally not a good guide to ascertaining bird densities because different areas/seasons
are not given the same amount of survey effort. In order to quantify the habitat use of
bird within the Study Area, with reference to data analysis on bird density
from other EIA studies ([25])([26]), corrected sighting densities have been
calculated in terms of number of bird individuals per effective trip per unit
area (the survey area mapped using a 1 km by 1 km grid (km2)). All surveys were conducted under sea
conditions of Beaufort <=5 and therefore all bird sightings were used for
data analysis.
8.6.2
Results
Bird Density (Grid Analysis)
Taking into account of all effective bird
sighting records, the grid analysis revealed that relatively higher bird
density (one to six bird individuals per effective trip per 1 km2)
was observed near shore, at Yung Shue Wan and the
open sea southwest of Lamma Island within the Project
Site (Figure 8.6).
Similar pattern was generally found in all seasons
but more birds were distributed over the open sea in Spring (one to three bird individuals per
effective trip per 1 km2, Figure 8.7) during the
migratory season.
Abundance and Distribution
A total of 2,214 individuals of 33 identified and
four unidentified bird species were recorded during the surveys (see Figures
8.8 & 8.9, Table 2 of
Annex
8). The recorded bird
species were classified in 6 groups, including Birds of Prey, Egrets &
Herons, Shorebirds (excluded Egrets & Herons), Gulls & Terns, Seabirds
(excluded Gulls & Terns) and Others (Table
8.4). About half of the
identified species are common and widely distributed in
Table 8.4 Bird
Species Recorded within the Study Area during the Surveys
|
Bird Group |
Family |
Common Name |
Species
Name |
|
Birds
of Prey |
Accipitridae |
Black
Kite |
Milvus migrans |
|
Accipitridae |
Common
Buzzard |
Buteo buteo |
|
|
Accipitridae |
White-bellied
Sea Eagle |
Haliaeetus leucogaster |
|
|
Egrets
& Herons |
Ardeidae |
Cattle
Egret |
Bubulcus ibis |
|
Ardeidae |
Chinese
Pond Heron |
Ardeola bacchus |
|
|
Ardeidae |
Great
Egret |
Ardea alba |
|
|
Ardeidae |
Little
Egret |
Egretta garzetta |
|
|
Ardeidae |
Pacific
Reef Egret |
Egretta sacra |
|
|
Ardeidae |
Unidentified
Egrets |
Family
Ardeidae |
|
|
Ardeidae |
Schrenck |
Ixobrychus eurhythmus |
|
|
Shorebirds
(excluded Egrets & Herons) |
Scolopacidae |
Eastern
Curlew |
Numenius madagascariensis |
|
Glareolidae |
Oriental
Pratincole |
Glareola maldivarum |
|
|
Scolopacidae |
Red-necked
Phalarope |
Phalaropus lobatus |
|
|
Gulls
& Terns |
Laridae |
Black-headed
Gull |
Larus ichthyaetus |
|
Laridae |
Black-legged
Kittiwake |
Rissa tridactyla |
|
|
Laridae |
Black-tailed
Gull |
Larus crassirostris |
|
|
Laridae |
Heuglin |
Larus heuglini |
|
|
Sternidae |
Aleutian
Tern |
Sterna
aleutica |
|
|
Sternidae |
Black-naped Tern |
Sterna
sumatrana |
|
|
Sternidae |
Bridled
Tern |
Sterna
anaethetus |
|
|
Sternidae |
Common
Tern |
Sterna
hirundo |
|
|
Sternidae |
Greater
Crested Tern |
Sterna
bergii |
|
|
Sternidae |
Little
Tern |
Sterna
albifrons |
|
|
Sternidae |
Roseate
Tern |
Sterna
dougallii |
|
|
Sternidae |
Whiskered
Tern |
Chlidonias hybridus |
|
|
Sternidae |
White-winged
Tern |
Chlidonias leucopterus |
|
|
Sternidae |
Unidentified
Terns |
Sterna
sp. |
|
|
Seabirds
(excluded Gulls & Terns) |
Alcidae |
Ancient
Murrelet |
Synthliboramphus antiquus |
|
Stercorariidae |
Arctic
Skua |
Stercorarius parasiticus |
|
|
Fregatidae |
Lesser
Frigatebird |
Fregata ariel |
|
|
Others |
Columbidae |
Feral
Pigeon |
|
|
Corvidae |
Large-billed
Crow |
Corvus macrorhynchus |
|
|
Corvidae |
Unidentified
Crow |
Corvus sp. |
|
|
Hirundinidae |
Barn
Swallow |
Hirundo rustica |
|
|
Motacillidae |
Unidentified
Pipit |
Anthus sp. |
|
|
Motacillidae |
Yellow
Wagtail |
Motacilla flava |
|
|
Sturnidae |
Crested
Myna |
Acridotheres cristatellus |
The detailed of the quantitative bird data are shown
in Tables 2 and 3 of Annex 8. Mean abundance and number of species
calculated for each bird group within the Study Area are presented in Table 8.5.
Table 8.5 Total and Mean
Abundance of Birds within Study Area during the Surveys
|
Bird Group |
Total no. of Individuals Recorded |
|
||||
|
Spring |
Summer |
Autumn |
Winter |
Overall |
||
|
Birds
of Prey |
328 |
184 |
75 |
136 |
723 |
|
|
Egrets
& Herons |
122 |
106 |
108 |
15 |
351 |
|
|
Shorebirds |
229 |
0 |
1 |
0 |
230 |
|
|
Gulls
& Terns |
327 |
208 |
118 |
139 |
792 |
|
|
Seabirds |
14 |
1 |
0 |
0 |
15 |
|
|
Others |
27 |
36 |
22 |
18 |
103 |
|
|
Total |
1,047 |
535 |
324 |
308 |
2,214 |
|
|
|
||||||
|
Bird Group |
Mean Abundance (No of Individuals per Survey Trip) |
% |
||||
|
Spring |
Summer |
Autumn |
Winter |
Overall |
||
|
(n = 9) |
(n = 9) |
(n = 6) |
(n = 3) |
(n = 27) |
||
|
Birds
of Prey |
36.4 |
20.4 |
12.5 |
45.3 |
26.8 |
33% |
|
Egrets
& Herons |
13.6 |
11.8 |
18.0 |
5.0 |
13.0 |
16% |
|
Shorebirds |
25.4 |
0.0 |
0.2 |
0.0 |
8.5 |
10% |
|
Gulls
& Terns |
36.3 |
23.1 |
19.7 |
46.3 |
29.3 |
36% |
|
Seabirds |
1.6 |
0.1 |
0.0 |
0.0 |
0.6 |
1% |
|
Others |
3.0 |
4.0 |
3.7 |
6.0 |
3.8 |
5% |
|
Total |
116.3 |
59.4 |
54.0 |
102.7 |
82.0 |
100% |
|
|
||||||
|
Bird Group |
Total no. of Species Recorded* |
|
||||
|
Spring |
Summer |
Autumn |
Winter |
Overall |
||
|
Birds
of Prey |
3 |
2 |
2 |
1 |
3 |
|
|
Egrets
& Herons |
6 |
3 |
5 |
2 |
7 |
|
|
Shorebirds |
3 |
0 |
1 |
0 |
3 |
|
|
Gulls
& Terns |
11 |
6 |
4 |
3 |
14 |
|
|
Seabirds |
2 |
1 |
0 |
0 |
3 |
|
|
Others |
2 |
2 |
4 |
4 |
7 |
|
|
Total |
27 |
14 |
16 |
10 |
37 |
|
*Note: the total number of species
recorded includes both identified and unidentified species.
Seabirds in particular Gulls and Terns had the
highest mean abundance (~36%) and number of species (14 observed species
including identified and unidentified species) during the surveys. Birds of Prey and Egrets and Herons had
the second highest mean abundance and number of observed species respectively. The five most abundant species recorded were Black
Kite Milvus migrans (~32%),
Little Egret Egretta garzetta (~11%),
Red-necked Phalarope Phalaropus lobatus
(~9%), Heuglin’s Gull Larus heuglini (~8%) and White-winged Tern Chlidonias leucopterus (~8%).
Seasonal variation in overall abundance and number of
observed species was also apparent in which numbers were highest in Spring and
lowest in Winter. Mean abundance
was highest in Spring and lowest in Autumn (Figure
8.9 & Table 8.5). Birds
of Prey, Egrets and Heron, Gulls and Terns were present all year within the
Study Area while Seabirds and Shorebirds were observed mainly in Spring (Figures 8.10 – 8.15).
Bird Activities and Elevation
Details of the activities and elevation data of each
bird species are shown in Table 4 of Annex
8. Tables 8.6 and Table 8.7 presented
the total number of individuals recorded under each bird activities and at
different elevation within the Study Area.
Table 8.6 Bird
Activities observed within Study Area during the Surveys
|
|
Total No. of Individuals
Recorded |
||||
|
Flying |
Soaring |
Foraging |
Resting |
Swimming |
|
|
Bird
Group |
|||||
|
Birds
of Prey |
344 |
298 |
56 |
21 |
4 |
|
Egrets
& Herons |
213 |
3 |
10 |
125 |
0 |
|
Shorebirds |
137 |
0 |
1 |
34 |
58 |
|
Gulls
& Terns |
453 |
0 |
73 |
265 |
1 |
|
Seabirds |
11 |
0 |
0 |
2 |
2 |
|
Others |
88 |
1 |
0 |
14 |
0 |
|
Total |
1,246 |
302 |
140 |
461 |
65 |
|
Season |
|||||
|
Spring |
741 |
121 |
9 |
111 |
65 |
|
Summer |
249 |
63 |
115 |
108 |
0 |
|
Autumn |
175 |
38 |
6 |
105 |
0 |
|
Winter |
81 |
80 |
10 |
137 |
0 |
|
Total |
1,246 |
302 |
140 |
461 |
65 |
During the surveys, most of the bird species observed
were either flying (~56%) or resting (~21%) within the Study Area. Small numbers of birds were seen soaring
(~14%), foraging (~6%) and swimming (~3%) in the area (Figure 8.8). Noticeable seasonal variation was also
observed in which more flying and swimming birds were seen in Spring during the migratory season while more foraging
activities were observed in Summer during the breeding season (Figure
8.9).
Table 8.7 Bird
Elevation observed within Study Area during the Surveys
|
|
Total No. of Individuals
Recorded |
|||
|
Sea-level 0 m |
Below Rotor Height (>0 – 14 m) |
Within Rotor Height* (>14 - 136m) |
Above Rotor Height (> 136m) |
|
|
Bird
Group |
||||
|
Birds
of Prey |
18 |
132 |
506 |
67 |
|
Egrets
& Herons |
113 |
174 |
64 |
0 |
|
Shorebirds |
97 |
105 |
28 |
0 |
|
Gulls
& Terns |
239 |
439 |
114 |
0 |
|
Seabirds |
7 |
5 |
3 |
0 |
|
Others |
3 |
79 |
21 |
0 |
|
Total |
477 |
934 |
736 |
67 |
|
Season |
||||
|
Spring |
154 |
505 |
375 |
13 |
|
Summer |
99 |
254 |
168 |
14 |
|
Autumn |
103 |
129 |
87 |
5 |
|
Winter |
121 |
46 |
106 |
35 |
|
Total |
477 |
934 |
736 |
67 |
*Note: the current data analysis has
taken into consideration that a maximum rotor diameter of 111 m maybe adopted
so that the number of bird individuals that fall within the range of rotor
strike shall represent a worse case.
The actual number of individuals affected would reduce should a smaller
diameter rotor be adopted for the final wind turbine design. Based on the latest design information
the actual rotor swept height will be within the 24-136m range. Consequently, the assessment presented
here (ie assuming a rotor swept height of 14-136m) is
conservayive.
Elevation of observed bird individuals were
categorised according to the rotor height (see Section 5 for wind turbine specification). Within the Study Area, over half (~ 64%)
of the total birds observed were either resting/below the rotor height
indicating that these bird species were generally staying/flying low over the
sea surface. More individuals
flying with an elevation range of 14 to 136m above sea level were observed in
the open sea in Spring while birds flying/soaring above 136m above sea level
(mainly Birds of Prey) were typically found close to the shoreline (see also Figure
8.9 & 8.10).
Individual bird groups also exhibited clear
behavioural patterns. Birds of
Prey, mainly the Black Kite, were generally seen flying/soaring particularly
along East Lamma Channel with height of 14 to 136m
above sea level while more individuals with this height were observed over the
open sea in spring (Figure 8.10). Most Egrets and Herons observed were
low-flying (<14m above sea level) near the coastline and over open sea while
some individuals were flying of height of 14 to 136m above sea level (Figure
8.11). Usually seen over open
sea in Spring, Shorebirds (excluded Egrets and
Herons), composed mainly of Red-necked Phalarope, exhibited more
resting/swimming activities and also low-flying during the surveys (Figure
8.12). Gulls and terns were
found in both near shore and offshore waters and were usually seen flying below
the rotor height. Most foraging
activities and large resting groups (> 25 individuals) were observed in the southwestern waters in Lamma
during Summer months (Figure 8.13). The remaining bird groups were mostly
flying with elevations below the rotor height (Figures 8.14 – 8.15).
Bird Species of Conservation Interest/ Selected Sensitive Species for
Further Assessment
There were five bird species of conservation interest
recorded within the Study Area during the surveys (see Table 2 of Annex 8). The distribution of these species is
shown in Figure 8.16.
·
White-bellied Sea Eagle Haliaeetus leucogaster – recognised as
Class II protected species in the PRC, listed as an indeterminate species in
the China Red Data Book and CITES Appendix II. It is an uncommon resident in
·
Black
Kite Milvus migrans – recognised as Class II protected
species in the PRC and CITES Appendix II.
It is a common and widespread resident in
·
Common
Buzzard Buteo buteo – recognised as Class II protected
species in the PRC and CITES Appendix II.
It is a common and widespread winter visitor in
·
Pacific
Reef Egret Egretta sacra – recognised as Class II protected
species in the PRC and CITES Appendix II.
It is an uncommon resident but widely distributed in coastal areas
throughout
·
Ancient Murrelet Synthliboramphus antiquus –
listed as a
vulnerable species in the China Red Data Book. This
winter visitor was only recorded in spring during the surveys and all
individuals recorded were flying over open sea with three individuals observed
below rotor height within the Project Site.
In addition, a
number of indicative bird groups have been identified to be particularly
sensitive, or potentially so, to wind farms ([27]) and these are listed as follows:
·
Gaviidae divers
·
Podicipedidae
grebes
·
Sulidae
gannets & boobies
·
Ciconiiformes
herons & storks
·
Anserini
swans and geese
·
Anatinae
ducks
·
Accipitridae
raptors
·
Sternidae
terns
·
Alcidae
alcids/auks
·
Strigiformes
owls
·
Gruidae
cranes
·
Passeriformes
especially nocturnal migrants
Based on the above list, as well as the flying
height, the abundance and the location of the bird species recorded, an
additional 16 species were selected for further assessment. The following subsection summarised the
results of each selected species (except for those species of conservation
interest already listed above).
Their distribution is shown in Figures 1 – 14 of Annex 8.
·
Chinese Pond Heron Ardeola bacchus – a common and widespread resident in
·
Little Egret Egretta garzetta – a common and
widespread resident in
·
Red-necked Phalarope Phalaropus lobatus – a common
passage migrant in
·
Aleutian Tern Sterna aleutica – an uncommon passage migrant in
·
Black-headed Gull Larus ichthyaetus (common winter visitor and passage migrant),
Black-tailed Gull Larus crassirostris
(uncommon winter visitor), and Black-legged Kittiwake
Rissa tridactyla (rare
winter visitor) – all species were recorded in low number during the
surveys. The gulls were observed
within the Project Site below the rotor height while the Black-legged Kittiwake
was seen flying within the rotor height (Figure 5 of Annex 8).
·
Black-naped Tern Sterna sumatrana – a common summer
visitor in
·
Bridled Tern Sterna anaethetus – a common summer visitor and breeding in
·
Common Tern Sterna hirundo – a common passage migrant in
·
Heuglin
·
Roseate Tern Sterna dougallii – an uncommon summer visitor and breeding in
·
Whiskered Tern Chlidonias
hybridus – an uncommon passage migrant in
·
White-winged Tern Chlidonias leucopterus – an
uncommon passage migrant in
·
Unidentified Terns Sterna sp.
– some unidentified terns were observed in Spring,
Summer and Autumn, usually flying below 14m and from 14 to 136m (Figure 13 of Annex 8).
·
Barn Swallow Hirundo
rustica – a common and widespread passage migrant
and summer visitor in
8.6.3
Existing Condition of the Wind Farm Site
The proposed Project Site is located at least 2 km away
from the nearest shoreline (Ha Mei Tsui) with a total
area of approximately 6 km2.
A total of 35 wind turbines, a wind monitoring mast and an offshore
substation ([28]) will be constructed. The turbines will be separated in
distances of about 650 m (East-West) and 360m (North-South). Preliminary dimensions are not expected
to exceed a maximum tip height of 136 m above mean sea level with a maximum
rotor diameter of 111 m.
Results of the literature review have indicated that
Heuglin’s Gull was the most abundant
species recorded within the Project Site, followed by White-winged Tern and
Common Tern. Although more individuals
were sighted in Spring, two large groups of Heuglin’s
Gull (group sizes of 49 and 59) were recorded in February 2009 resting within
the Project Site. Most of the
species recorded were flying while 10 individuals of Black Kite and one
individual of Heuglin’s Gull were foraging in the
area (Figure 8.18 and Figure
9 of Annex 8). Most of the flying activities were
below/above rotor height (<14m or >136m above sea level) with 44
individuals recorded within the rotor height (see also Figure 8.9).
Table 8.8 Bird
Species observed within the Project Site during the Surveys
|
Bird Species |
Total no. of individuals recorded |
||||
|
Season |
Spring |
Summer |
Autumn |
Winter |
Total |
|
Aleutian Tern |
0 |
2 |
13 |
0 |
15 |
|
Ancient Murrelet |
3 |
0 |
0 |
0 |
3 |
|
Barn Swallow |
2 |
0 |
3 |
0 |
5 |
|
Black Kite |
6 |
0 |
0 |
10 |
16 |
|
Black-headed Gull |
0 |
0 |
0 |
2 |
2 |
|
Black-naped Tern |
2 |
5 |
0 |
0 |
7 |
|
Black-tailed Gull |
1 |
0 |
0 |
0 |
1 |
|
Bridled Tern |
0 |
3 |
0 |
0 |
3 |
|
Common Tern |
1 |
2 |
14 |
0 |
17 |
|
Heuglin |
2 |
0 |
0 |
129 |
131 |
|
Little Tern |
1 |
0 |
0 |
0 |
1 |
|
Red-necked Phalarope |
7 |
0 |
0 |
0 |
7 |
|
Unidentified Terns |
0 |
0 |
1 |
0 |
1 |
|
Whiskered Tern |
0 |
0 |
2 |
0 |
2 |
|
White-winged Tern |
20 |
0 |
0 |
0 |
20 |
|
Bird Activity |
F |
S |
Fo |
R |
S |
|
Aleutian Tern |
6 |
0 |
0 |
9 |
0 |
|
Ancient Murrelet |
3 |
0 |
0 |
0 |
0 |
|
Barn Swallow |
5 |
0 |
0 |
0 |
0 |
|
Black Kite |
6 |
0 |
10 |
0 |
0 |
|
Black-headed Gull |
0 |
0 |
0 |
2 |
0 |
|
Black-naped Tern |
7 |
0 |
0 |
0 |
0 |
|
Black-tailed Gull |
0 |
0 |
0 |
0 |
1 |
|
Bridled Tern |
2 |
0 |
0 |
1 |
0 |
|
Common Tern |
15 |
0 |
0 |
2 |
0 |
|
Heuglin |
12 |
0 |
1 |
118 |
0 |
|
Little Tern |
0 |
0 |
0 |
1 |
0 |
|
Red-necked Phalarope |
0 |
0 |
0 |
5 |
2 |
|
Unidentified Terns |
1 |
0 |
0 |
0 |
0 |
|
Whiskered Tern |
2 |
0 |
0 |
0 |
0 |
|
White-winged Tern |
20 |
0 |
0 |
0 |
0 |
|
Elevation |
0m |
>0 – 14m |
>14 – 136m |
> 136m |
|
|
Aleutian Tern |
9 |
4 |
2 |
0 |
|
|
Ancient Murrelet |
3 |
0 |
0 |
0 |
|
|
Barn Swallow |
0 |
5 |
0 |
0 |
|
|
Black Kite |
0 |
10 |
6 |
0 |
|
|
Black-headed Gull |
2 |
0 |
0 |
0 |
|
|
Black-naped Tern |
0 |
5 |
2 |
0 |
|
|
Black-tailed Gull |
1 |
0 |
0 |
0 |
|
|
Bridled Tern |
1 |
2 |
0 |
0 |
|
|
Common Tern |
2 |
13 |
2 |
0 |
|
|
Heuglin |
118 |
2 |
11 |
0 |
|
|
Little Tern |
1 |
0 |
0 |
0 |
|
|
Red-necked Phalarope |
5 |
2 |
0 |
0 |
|
|
Unidentified Terns |
0 |
0 |
1 |
0 |
|
|
Whiskered Tern |
0 |
2 |
0 |
0 |
|
|
White-winged Tern |
0 |
0 |
20 |
0 |
|
*Note: Bird Activities: F = Flying, S
= Soaring, Fo = Foraging, R = Resting, S = Swimming
Of the five species of species of conservation
interest, Black Kite and Ancient Murrelet, were the
only two recorded species within the Project Site during the surveys.
8.7
Summary
of Terrestrial Ecological Resources
The avifauna habitats of the Study Area include nearshore and offshore marine waters in southwest
The Project Site has an
area of approximately 600 ha and comprises offshore waters located about 2 km
away from the nearest shoreline.
Literature reviews suggested that the area could be within the flying
route of migratory birds and focussed surveys revealed relatively high
abundance of birds south of the Project Site especially in Winter. This implies that the migratory pathway
of some species could pass through the Project Site. A few species also showed potential
usage of the Project Site by foraging/resting. A total of 14 identified and one unidentified
species was recorded with Heuglin’s Gull,
White-winged Tern and Common Tern having relatively higher abundance. Two species of conservation interest
were recorded including Black Kite and Ancient Murrelet.
The lists and evaluations of the bird species of
ecological interest recorded within the Study Area, according to the EIAO-TM,
are given in Table 8.9.
Table 8.9 Bird
Species with Ecological Interest Recorded within the Study Area
|
Species |
Location |
Protection Status |
Distribution |
Rarity |
|
White-bellied
Sea Eagle Haliaeetus leucogaster |
Flying/soaring
and resting around |
Protected under
WAPO (Cap 170) in HK, Class II Protected Animal of PRC, CITES Appendix II |
Found in
coastal area of |
Uncommon
resident in |
|
Black Kite Milvus lineatus |
Mainly
flying/soaring over large area within Study Area; found flying/foraging
within Project Site |
Protected under
WAPO (Cap 170) in HK, Class II Protected Animal of PRC, CITES Appendix II |
Found in many
types of habitats; |
Common and
widespread in |
|
Common Buzzard Buteo buteo |
Soaring in open
sea around Tung O Wan |
Protected under
WAPO (Cap 170) in HK, Class II Protected Animal of PRC, CITES Appendix II |
Found in open area in Hong Kong, |
Common and widespread in |
|
Pacific Reef Egret Egretta sacra |
Resting/flying/foraging
along shoreline within the Study Area |
Protected under
WAPO (Cap 170) in HK, Class II Protected Animal of PRC |
Found in coastal habitats in |
Uncommon but widespread in |
|
Ancient
Murrelet Synthliboramphus antiquus |
Flying over
open sea |
Protected under
WAPO (Cap 170) in HK, Vulnerable in |
Found in offshore waters in |
Scare winter visitor in |
A desktop literature review and extensive avifauna
field surveys (see Sections 8.4 – 8.6) were conducted in order to establish the ecological resources for
avifauna within and surrounding the Study Area. The importance of potentially impacted
avifauna resources identified within the Study Area was assessed using the
methodology defined in the EIAO-TM.
The potential impacts due to the construction and operation of the wind
farm were then assessed (following the EIAO-TM Annex 16
guidelines) and the impacts evaluated (based on the criteria in EIAO-TM
Annex 8).
In addition, where
necessary, assessment will make reference to other EIAs
conducted elsewhere for wind farm development projects, particularly in
8.9
Potential Sources
of Impacts on Birds
In this section of the report, the potential for avifauna
associated with various marine works and activities involved in the proposed
project are examined in detail. The
significance of a potential impact from works or activities on birds can be
determined by examining the consequences of the impact on the affected bird
species.
Habitat loss, habitat fragmentation/isolation and
disturbance to wildlife are the typical ecological impacts due to the
development projects. International
EIAs and scientific studies conducted by Birdlife International
and Royal Society for the Protection of Birds (RSPB) have also identified the
following potential impacts identified on
birds and their movement due to the development of wind farm ([29])([30])([31]):
·
Habitat
loss/ avoidance/ disturbance;
·
Creation
of a barrier effect to bird movement including displacement or exclusion; and,
·
Collision
mortality.
Each of the potential impacts on birds mentioned
above is discussed detailed below.
8.9.1
Construction Phase
Habitat Loss
·
Permanent
loss of open water habitats (approximately 0.16 ha footprint area) due to the
construction of wind turbine foundations, offshore substation and offshore
monitoring mast (details see Section
9.5.1).
·
The
physical loss of habitat due to the Project could potentially affect some
individuals of the frequently sighted bird species that utilise the southwest Lamma waters.
This may potentially reduce the species abundance/diversity in the area.
·
Based
on the vessel-based survey findings, although a comparatively higher density
was recorded within the Project Site (231 individuals in 14 identified and one
unidentified species, mean density was 1.4 individuals per effective survey
trip per km2), most species recorded were flying over the area (11
identified species) or resting (7 identified species) with limited number
foraging and swimming (2 identified species) in the area. The affected southwest Lamma
waters in the vicinity of the Project Site are not used as important foraging
area. For this reason, the
relatively small scale loss of approximately 0.16 ha of open waters within the
Project Site is not expected to be significant for bird/migratory bird populations. The loss of these open waters would represent
a very minor loss of marine habitat in the context of the size of marine areas
in the range of these birds.
Provided the recommended mitigation measures are followed during
construction, no unacceptable adverse impacts on bird individuals that utilise
southwest Lamma waters are anticipated.
·
Information
from the fisheries impact assessment (Section
10) indicates that the permanent loss of a small area of marine habitat due
to the construction works are not predicted to adversely impact fisheries resources. As a result, impacts to birds through
the loss of small area of feeding ground (the fisheries resources in the marine
habitat serve as bird’s food prey) are not predicted to be significant.
·
Direct
impacts due to cable installation works to the birds are not expected to be
severe as the construction works would not cause any permanent loss of the
marine water habitats in the area.
·
Other
International EIAs conducted elsewhere also reached
similar conclusions that impacts on birds through the loss of food resources by
direct habitat loss are considered negligible/small-scale for the bird
populations using the area ([32])([33]).
Other Impacts
·
Secondary
impacts to birds may arise from the potential of increased noise impact through
piling for foundations of turbines, monitoring mast and offshore substation,
human activities and disturbance, and disposal of construction waste. The impacts are expected to be low owing
to the temporary nature of the construction works. It should also be noted that the marine
traffic volume in this part of
8.9.2
Operational Phase
Habitat Avoidance/Disturbance
Barrier Effect
It is suggested that wind turbines may act as
barriers to bird movement such that instead of flying between the turbines, the
birds may fly around the outside of the cluster ([35]).
This may consequently displace the bird movement/flight path and
subsequently disrupt the ecological links between feeding, breeding and
roosting areas.
The spacing of turbines may alleviate any barrier
effect by allowing wide corridors.
It has been suggested that gulls have been able to regularly fly between
turbines spaced 200 m apart ([36]).
At present, the preliminary wind farm design will allow distances of 650
m (East-West) and 360m (North-South) between turbines. Surveys results also revealed that flying
routes of most birds tended to be near coastal areas (especially those along
East Lamma Channel) and only occasionally passed
through offshore waters ie the proposed Project
Site.
It is generally believed that the local flying path
of the migratory species such as gulls and terns follow coastal areas from the
south when arriving to breed, and there exist many corridors of entry to the
HKSAR coastline and these birds will travel around the coastline away from
exposed offshore areas ([37]).
In view of there being similar marine water habitats in
the vicinity of Project Site as flying corridor and limited usage by avifauna
around the waters in close proximity to and within the Project Site, it is
anticipated that the barrier effect due to the operation of the wind turbines
and wind monitoring mast will not cause any unacceptable impacts to the
migratory bird species.
Glare/Noise Disturbance
Potential disturbance on the vision of flying birds
will be minimised by the use of non-reflective colour scheme of the wind
turbines and wind monitoring mast, which would not cause glare during
operation.
Noise generated by the wind turbine may potentially
cause disturbance on bird movement.
Experiments on the detectability of wind
turbine blades noise by birds revealed that the sound level generated under windy
environment is probably less audible to birds than humans ([38]).
The noise produced by the operating wind turbine and monitoring mast
will be at a low, constant and predictable sound level to minimise the noise
disturbance. Since the wind turbine
site is not considered to be an important bird habitat, the noise impacts to
bird are expected to be low.
Collision Risk
Mortality due to collisions between birds and wind
farm structures including turbines and monitoring mast remains the major
concern in impact assessment, although actual collision rate is low in
operating wind farms due to avoidance ([39])([40]).
Such risk is species-dependent, site-specific and can be easily
influenced by weather conditions. Evidence
suggests that the risk of collision increases during periods of bad weather and
poor visibility ([41]).
Collision risk was estimated for the identified
species recorded within the Assessment Area including the Project Site (Figure 15 of Annex
8), with a total area of 2,000 ha.
This assessment adopted the worse-case scenario by assuming that all
birds sighted within the assessment area will pass through the Project Site
(~600 ha). This may lead to an
over-estimation in the predicted collision risk and consequently should be
noted when interpreting the results.
Within the Assessment Area, all bird species recorded were selected for
individual assessment of its collision risk. However, some bird species were not
included in the assessment because all individuals recorded within the
Assessment Area were below the rotor height during the surveys and thus the
risk cannot be determined by the adopted calculations (Table 5 of Annex 8. This included Ancient Murrelet, Artic Skua, Barn Swallow, Black-headed Gull, Black-tailed Gull,
Bridled Tern, Greater Crested Tern, Little Tern and Whiskered Tern. The bird species assessed include:
·
Aleutian Tern
·
Black Kite
·
Black-legged Kittiwake
·
Black-naped Tern
·
Common Tern
·
Heuglin’s Gull
·
Red-necked Phalarope
·
White-bellied Sea Eagle
·
White-winged Tern
In this assessment, Collision Risk Model (CRM)
developed for Scottish National Heritage is used to calculate the collision
risk (see Annex 8 for detailed methodology adopted) ([42]).
CRM has been generally accepted to estimate bird collision risk in
impact assessment of bird for various wind farm development projects ([43])([44])([45]).
In addition, we have estimated the risk in two different situations. The first situation is that birds fly as
if the wind turbine structures and rotors were not there and take no avoiding
action (ie death). In reality most birds do take avoiding
action and therefore the collision risk is usually adjusted by the avoidance
factor. It is suggested that an
avoidance rate of 95% is conservative enough for collision risk assessment ([46]).
The following presents the results of individual
assessment for each species, followed by an overall assessment of the
impact. The calculations of
collisions are detailed in Tables 6 - 7
of Annex 8 and Table
8.10 presents the summary results of the number of collisions predicted in
each season for each species.
Table 8.10 Number
of Bird Collisions Predicted (Number per Season) within the Assessment Area (a
total of 20 km2)
|
Species |
No. of Collision 95% Avoidance (No Avoidance) |
|||
|
Spring |
Summer |
Autumn |
Winter |
|
|
Aleutian Tern |
0 (0) |
0 (0) |
0.19 (3.76) |
0 (0) |
|
Black Kite |
2.97 (59.5) |
0 (0) |
0 (0) |
0.69 (13.87) |
|
Black-legged
Kittlewake |
0 (0) |
0 (0) |
0 (0) |
0.03 (0.64) |
|
Black-naped Tern |
0.02 (0.43) |
0 (0) |
0 (0) |
0 (0) |
|
Common Tern |
0.18 (3.69) |
0.07 (1.5) |
0.18 (3.69) |
0 (0) |
|
Heuglin's Gull |
0.22 (4.49) |
0 (0) |
0 (0) |
0.15 (3.01) |
|
Red-necked
Phalarope |
0.16 (3.17) |
0 (0) |
0 (0) |
0 (0) |
|
White-bellied
Sea Eagle |
0.01 (0.28) |
0 (0) |
0 (0) |
0 (0) |
|
White-winged
Tern |
0.04 (0.76) |
0 (0) |
0 (0) |
0 (0) |
Aleutian Tern
Within the Assessment Area, Aleutian Tern were sighted
in Autumn only during the surveys and number of collisions predicted was 3.76
birds per season under no avoidance situation. After applying the 95% avoidance factor,
the number of collisions predicted is 0.19 birds per season (only in
Autumn). The number predicted
under 95% avoidance is considered negligible when compared with the
total number of individuals recorded during the surveys (~0.2% of 85
individuals) and the highest daily peak count documented in Hong Kong ([47]) (~0.1%
of 190 individuals). The impact of
collision to this bird species is therefore not considered adverse.
Black Kite
Within the Assessment Area, Black Kite were sighted in
Spring and Winter only during the surveys and the number of collisions
predicted is 59.5 birds per season in Spring and 13.87 birds per season in
Winter under no avoidance situation.
After applying the 95% avoidance factor, the number of collisions
predicted is 2.97 birds per season and 0.69 birds per season in Spring and
Winter respectively. The numbers
predicted under 95% avoidance are considered negligible when compared with the
total number of individuals recorded during the surveys (<0.4% of 712
individuals) and the highest daily peak count documented in
Black-legged Kittiwake
Within the Assessment Area, Black-legged Kittiwake
were sighted in Winter only during the surveys and the number of collision
predicted is 0.64 birds per season (only in Winter) under no avoidance
situation. After applying the 95%
avoidance factor, the number of collisions predicted is 0.03 birds per season
(only in Winter). The number
predicted under 95% avoidance is considered low when compared with the total
number of individuals recorded during the surveys (~3% of one individual). Information of the observation records
for this species was however not available. The impact of collision to this bird
species is therefore not considered adverse.
Black-naped Tern
Within the Assessment Area, Black-naped
Tern were sighted in Spring only during the surveys and the number of
collisions predicted is 0.43 birds per season (only in Spring) under no
avoidance situation. After applying
the 95% avoidance factor, the number of collisions predicted is 0.02 birds per
season (only in Spring). The number
predicted under 95% avoidance is considered negligible when compared with the
total number of individuals recorded during the surveys (~0.02% of 101 individuals)
and the estimated breeding population in Hong Kong ([49]) (~0.01%
of over 200 individuals). The
impact of collision to this bird species is therefore not considered adverse.
Common Tern
Within the Assessment Area, Common Tern were sighted
in Spring, Summer and Autumn during the surveys. Numbers of collisions predicted in
Spring, Summer and Autumn are 3.69 birds per season, 1.50 birds per season and
3.69 birds per season respectively under no avoidance situation. After applying the 95% avoidance factor,
the numbers of collisions predicted in Spring, Summer and Autumn are 0.18 birds
per season, 0.07 birds per season and 0.18 birds per season respectively. The numbers predicted under 95%
avoidance are considered negligible when comparing with the total number of
individuals recorded during the surveys (<0.17% of 107 individuals) and the
highest daily peak count documented in
Heuglin’s Gull
Within the Assessment Area, Heuglin’s
Gull were sighted in Spring and Winter only during the surveys and the numbers
of collisions predicted in Spring and Winter are 4.49 birds per season and 3.01
birds per season respectively under no avoidance situation. After applying the 95% avoidance factor,
the numbers of collisions predicted in Spring and Winter are 0.22 birds per
season and 0.15 birds per season respectively. The numbers predicted under 95%
avoidance are considered negligible when compared with the total number of
individuals recorded during the surveys (<0.12% of 183 individuals) and the
highest daily peak count documented in
Red-necked Phalarope
Within the Assessment Area, Red-necked Phalarope were
sighted in Spring only during the surveys and the number of collisions
predicted in Spring is 3.17 birds per season under no avoidance situation. After applying the 95% avoidance factor,
the number of collisions predicted in Spring is 0.16 birds per season. The number predicted under 95% avoidance
is considered negligible when compared with the total number of individuals
recorded during the surveys (~0.08% of 207 individuals) and the highest daily
peak count documented in Hong Kong ([52]) (~0.02% of 952 individuals). The impact of collision to this bird
species is therefore not considered adverse.
Within the Assessment Area,
White-winged Tern
Within the Assessment Area, White-winged Tern were
sighted in Spring only during the surveys and the number of collisions
predicted is 0.76 birds per season under no avoidance situation. After applying the 95% avoidance factor,
the number of collisions predicted is 0.04 birds per season (only in
Spring). The number predicted under
95% avoidance is considered negligible when compared with the total number of
individuals recorded during the surveys (<0.02% of 178 individuals) and the
highest daily peak count document in
Based on the above assessment, Black Kite has the
highest number of collisions with 2.97 birds per season (only in Spring and Winter) under 95% avoidance rate. It should be noted that the calculated
numbers are likely to be over-estimated based on the conservative assumptions
included in the assessment.
Nonetheless, the predicted numbers of collisions in each species is
generally low, which is probably attributable to the low numbers of individuals
recorded flying within the rotor risk height.
Numbers of bird collision/strike predicted in other
studies/international EIAs varied greatly due to
different assumptions, methodology and population estimates used. Some revealed the range of 0.6 to 37
birds per turbine per year ([55])([56])
while others expressed the
risk as the annual number ranging from 0.01 to 4.6 per turbine per year ([57])([58]).
In terms of seasonal prediction, the number ranges from 0.102 birds per
turbine per season (under 99.8% avoidance rate) ([59]) to 45 birds per season (accounting for
0.02% of total population of the selected species) ([60]).
Although information on mortality rate and population estimates is not
readily available in
In addition, monitoring of operating wind farms has shown
that birds do exhibit of avoidance behaviour ([61]),
resulting in generally low collision mortality rates per turbine ([62]). In Hong Kong, no bird collision/carcass was
recorded by the monthly bird monitoring conducted during the operation of the
onshore wind turbine in Lamma Island from March 2006
to February 2007 ([63]). This implies that the actual collision
rate could be much lower than that predicted in the EIA studies. In this Study, a comprehensive site
selection study has been carried out such that the by siting
the wind turbine away from habitat and area with significant ecological
interests, such as Country Parks, SSSI, Special Area and Restricted Areas; as
well as important bird habitat (ie breeding sites of
Roseate Tern, Black-naped Tern and Bridled Tern,
nesting sites and frequent utilising areas of
White-bellied Sea Eagle) or as important routes of migratory birds (higher
density of seabirds occurred in southern waters between southeastern Lamma and Po Toi and southeastern
Hong Kong waters ([64])) (see Figure 8.2 and Section 3).
It has also been suggested that lighting of turbines
for safety/navigation purpose has the potential to attract nocturnal migrant
birds at night and subsequently increase the collision risk, especially in
conditions of poor visibility ([65]). These nocturnal migrants
are usually small songbirds (Order Passeriformes) including
warblers, hummingbirds and flycatchers, which are commonly found in woody areas
and not over open sea. Within the
Assessment Area, low number of Barn Swallow (a passerine) was observed with no
individuals flying at rotor height; which suggested that the area is not an
important habitat for this species.
Although some shorebirds and seabirds also exhibit nocturnal
migration, their relatively low abundance suggested that the study area is not
an important habitat for these species.
The effects of
lighting on birds in terms of light colour, type, duration on and intensity
remain poorly unknown ([66]) ([67]) and no conclusive
recommendation has been made. It is noted that aviation warning
lights of low intensity will be installed on top of the nacelle of the wind
turbine, monitoring mast and offshore substation to alert vessels during
periods of poor visibility. The
impacts due to the light of these structures are expected to be minimal
as the Project Site and areas
in the vicinity are not an important bird habitat and have relatively low
utilisation.
Overall, in view of the limited number of birds
flying within the risk height within the Project Site, it is anticipated that
the collision risk due to the operation of the wind turbines and wind monitoring
mast is low and will not cause any unacceptable impacts to these migratory bird
species.
8.9.3
Cumulative Impact
At present, there are no planned projects at
8.10
Evaluation Of the
Impacts To Birds
The following section discusses and evaluates the
significance of the impacts to avifauna (particularly migratory birds)
identified in the previous section.
Based upon the information presented above, the significance of bird
impacts associated with the construction and operation of the wind farm have
been evaluated in accordance with the EIAO-TM
(Annex 8, Table 1) and presented in Table
8.11.
Table 8.11 Overall
Impact Evaluation for Avifauna
|
Evaluation Criteria |
Birds |
|
Habitat quality |
The Project Site is located in the
southwest Lamma waters (approximately 2 km from the
nearest shoreline) where sightings of birds (especially migratory birds) are
low to moderate and higher sightings were recorded in Spring. In view of the present condition of
the Project Site, as well as other areas within the Study Area, the marine
water habitat within the Project Site is not an important bird habitat or
important flight path of migratory birds. |
|
Species |
Bird
species of conservation interest recorded within the Study Area include A total of
14 identified and one unidentified species were recorded including Aleutian
Tern, Ancient Murrelet, Barn Swallow, Black Kite,
Black-headed Gull, Black-naped Tern, Black-tailed
Gull, Bridled Tern, Common Tern, Heuglin’s Gull,
Little Tern, Red-necked Phalarope, Whiskered Tern, White-winged Tern and Barn
Swallow, two of which were considered bird species of
conservation interest (Black
Kite and Ancient Murrelet). |
|
Size/Abundance |
Relatively
small scale loss of approximately 0.16 ha of open waters within the Project
Site (~600 ha) comparing to the similar habitats within the Study Area
(~25,800 ha). Bird
species were found to be infrequently utilising the Project Site during the
baseline surveys (most of them were flying). The relatively high mean density
recorded within the Study Area was mainly attributable to the occurrence of
the Heuglin’s Gull (mostly resting) and
white-winged Tern (mostly flying).
Reduction of species abundance/diversity and ecological carrying
capacity will not be expected. |
|
Duration |
The impact will be low and
temporary during the construction phase – the construction of wind monitoring
mast and wind turbine is expected to last for about 6 months and 9 months
respectively. The impact will persist during the
operational phase but is not predicted to cause adverse impacts to birds due
to the offshore location (> 2km) and limited number of bird flying within
rotor risk area of the Project Site. |
|
Reversibility |
The impacts will be permanent and
irreversible with the existence of the wind farm. |
|
Magnitude |
The risks of collision of
the bird species and operational noise impacts to birds are not considered to
be significant, particularly considering that the wind farm will be operated
in offshore waters with moderate sightings of migratory birds. |
|
Overall Impact Conclusion |
Low to Moderate |
In view of the offshore location and low to moderate
magnitude of impacts on birds, reduction of species abundance/diversity and
ecological carrying capacity due to marine water habitats consumed for the
development of wind farm are not expected.
Overall operational impacts
on birds are not expected to cause adverse impacts and are therefore considered
to be low to moderate.
Annex 16 of the EIAO-TM states that the general policy for mitigation of significant
ecological impacts, in order of priority, is:
Avoidance:
Potential impacts should be avoided to the maximum extent practicable by
adopting suitable alternatives;
Minimisation:
Unavoidable impacts should be minimised by taking appropriate and
practicable measures such as constraints on intensity of works operations 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.
At each stage, residual impacts are to be re-assessed
to determine whether there is a need to proceed to the next stage of
mitigation. The following measures
have been developed in accordance with this approach to mitigate the
impacts.
8.11.1
Avoidance
The Southwest wind farm site was proposed based on the
following considerations:
·
Avoid habitat and area with significant ecological interests, such as
·
Avoid adverse impacts to birds by siting the
wind turbine and monitoring mast away from important bird habitat (ie breeding sites of Roseate Tern, Black-naped Tern and Bridled Tern, nesting sites and frequent utilising areas of
8.11.2
Minimisation
The previous discussion in Section 8.9 has
indicated that the potential ecological impacts due to the construction and
operation of a wind farm at the Project Site are considered to be low. The following measures are recommended
to further reduce the potential impacts and disturbance to the surrounding
habitats.
·
In
addition to the requirement from Civil Aviation Department (CAD), extreme level
of lighting should be avoided as to minimise the numbers of birds attracted to
the wind turbine at night. Lighting
should be of low intensity.
·
The
construction should adopt good construction/operation practices to minimise the
impact of construction/operation on marine water habitat (such as no dumping of
rubbish or chemicals, see Section 9).
There will be the permanent loss of approximately
0.16 ha of marine water habitats (in terms of open waters/ subtidal
soft bottom habitats). Since the
wind farm structures would not be located at important bird habitat or on travelling routes
of migratory birds, the
potential residual impacts due to bird collision with the operating wind turbines and
monitoring mast are considered to be minor and of low magnitude and
significance. No adverse residual impact due to the
construction of the wind turbine is expected after the implementation of the
proposed mitigation measures.
8.13
Environmental
Monitoring and Audit
The implementation of the ecological mitigation
measures stated in Section 8.11.2 should
be checked as part of the environmental monitoring and audit procedures during
the construction and operation period.
Although no adverse residual impacts are envisaged based on
the results of impact assessment, monitoring for bird abundance and distribution
for one year of pre-construction phase, one year of the construction
phase ([68])
and the first year of
operation phase is recommended.
The
purpose of the construction and operation monitoring is to investigate the
temporal variation in species occurrence, abundance and distribution of birds
before and after the commencement of the wind farm. Particular focus will be made on species
of conservation interest (especially the Birds of Prey including
Traditional vessel-based survey will be applied for
pre-construction, construction and operation monitoring, which
will be undertaken at once per week during migratory season (March to May) and
at once/twice per month for the rest of the year. Line transects survey method will be
used at designated sampling locations within the Project Site. Locations of sampling transects will be finalised during the detailed design stage (after
confirmation of the types and siting of the
turbines).
The results will be
reviewed and analysed after the operation monitoring
period. Should bird abundance be
significantly different (taking into account naturally occurring alterations to
distribution patterns such as due to seasonal change) to the pre-construction
activity (following the operation monitoring), recommendations for a further
operation monitoring survey will be made.
Data should then be re-assessed and the need for any further monitoring
established. Significance levels
will be quantitatively determined following the operation monitoring which will
review up-to-date publicly available information on bird distribution to allow
for typical variance levels.
If, after the first-year
operation monitoring period, insignificant variation in bird abundance have
been reported then the monitoring will be ceased, as it will have been
confirmed that the wind turbine is not having an adverse impact on bird
species.
The proposed
A total of 14 identified species were recorded in the
Project Site including Aleutian Tern, Ancient Murrelet,
Barn Swallow, Black Kite, Black-headed Gull, Black-naped
Tern, Black-tailed Gull, Bridled Tern, Common Tern, Heuglin’s
Gull, Little Tern, Red-necked Phalarope, Whiskered Tern and White-winged Tern,
two of which were considered bird species of conservation interest (Black Kite
and Ancient Murrelet). In addition, in the wider Study Area a
further three bird
species of conservation interest were recorded, including White-bellied Sea Eagle, Common Buzzard and Pacific Reef
Egret. Most of the birds that are
of conservation interest are common and widespread in Hong Kong with the
exception of Pacific Reef Egret (uncommon but widespread resident),
Potential construction phase impacts to birds may
arise from the permanent loss of habitats due to the construction of wind
turbine foundation, substation and monitoring mast; temporary disturbance and
displacement of birds. The
relatively small scale loss of approximately 0.16 ha of open waters within the
Project Site is not expected to be significant for bird/migratory bird
populations in view of similar habitats in the vicinity and the limited bird
use in the area. The direct
ecological impact due to the construction of the wind farm is expected to be
low, and will not contribute to any potential cumulative impact. Barrier
effect to bird movement and bird collisions during the operation of the wind
farm were assessed. Aleutian Tern, Ancient Murrelet
and Barn Swallow, Black Kite, Black-headed Gull, Black-naped
Tern, Black-tailed Gull, Bridled Tern, Common Tern, Heuglin’s
Gull, Little Tern, Red-necked Phalarope, Whiskered Tern, White-winged Tern have
utilised the Project Site and therefore are the
species that may be affected by the operation of the wind farm. However, these species were recorded in
relatively low numbers and most of them were flying below the rotor area. Since the wind farm is not located within important
bird habitat or on the flight path of migratory birds, the potential risk of
bird collision will be low. In
addition, collision risk assessment using the
worse case scenario also predicted low number of bird collision. Overall, no adverse residual impacts are envisaged.
A bird monitoring programme will be undertaken to confirm
that the construction and operation of the wind turbines will not cause adverse
impacts to birds. Monitoring for
bird abundance and distribution will be undertaken for one year during the
pre-construction phase, one year during the construction phase for the wind
turbines and the first year of the operation of the turbines.