|
Consultancy
Ref.: AFCD/FIS/02/19 Consultancy Service for Environmental Impact Assessment
Study for Designation of New Fish Culture Zones Environmental
Impact Assessment (EIA) Report for Establishment of Fish Culture Zone at
Outer Tap Mun November
2022 |
This Section
presents the findings of an assessment of potential impacts on existing capture
and culture fisheries, including fisheries resources, fishing operations and
fish culture activities associated with the construction and operation of the
proposed Project with the available Project information to-date.
The
criteria for evaluating fisheries impacts are stated in the Technical Memorandum on Environmental Impact
Assessment Process (EIAO-TM). Annex 17 of the EIAO-TM prescribes the general approach and methodology for the
assessment of fisheries impacts deriving from a project or proposal, to allow a
complete and objective identification, prediction and evaluation of the
potential impacts. EIAO-TM Annex 9 recommends the criteria that are to be used for
evaluating fisheries impacts.
Other legislation which
applies to fisheries includes:
§ Fisheries Protection Ordinance
(Cap. 171), which provides for conservation
of fish and other aquatic life, regulates fishing practices and prevents
activities detrimental to the fishing industry;
§ Marine Fish Culture Ordinance (Cap.
353), which regulates and protects
marine fish culture and other related activities and requires all marine fish
culture activity to operate under licence in designated FCZs;
§ Water Pollution Control Ordinance
(Cap. 358), which aims to control water
pollution in Hong Kong waters. Water
Control Zones (WCZs) are designated with individual water quality objectives to
promote the conservation and best use of those waters in the public interest;
and
§ Environmental Impact Assessment
Ordinance (Cap. 499), the Study Brief Section 3.4.5 and
Appendix D which outline the key fisheries impacts to be reviewed and assessed
in this EIA report.
In accordance with Clause 3.4.5.2
of the Study Brief, the Assessment Area for fisheries impact assessment (Figure
A1.1 of Appendix 5A) shall be the
same as the assessment area for Water Quality Impact Assessment covering the
Mirs Bay Water Control Zone (WCZ) and the Tolo Harbour and Channel WCZ. Detailed description of the physical and
biological characteristics of the marine environment of the Assessment Area is
provided in Section 3 and Section
4 respectively.
A literature review was conducted to review the
baseline fisheries conditions within the Assessment Area and to identify
information gaps to determine whether field surveys are required to provide sufficient
information for the fisheries impact assessment. Findings of the literature review are
presented in Sections 5.3.2.1 to 5.3.2.6.
Commercial fishing
operations in Hong Kong are broadly identified into culture and capture
fisheries. Marine-based culture fishery operations occur at 26
FCZs which altogether occupy about 209 ha of Hong Kong waters with some 920
licensed operators. They involve rearing
of marine fish from fry or fingerlings to marketable size in cages suspended by
floating rafts usually in sheltered coastal areas. Fish farms are typically small scale
operations comprising only one or two rafts with an average total size of about
304 m2 ([1]).
With effect from June 2002, the
marine fish culture licence is transferable.
The existing moratorium for FCZs has been reviewed and was partially
lifted in 2013 to launch a pilot scheme for the issuance of new marine fish
culture licenses (MFCLs). Ten MFCLs were
issued in three FCZs with surplus carrying capacity, including the O Pui Tong,
Wong Wan and Sham Wan FCZs, in which four licences remained valid, with three
at Wong Wan FCZ and one at Sham Wan FCZ by the end of 2018 ([2]).
In 2021, the
marine fish culture industry produced about 332 tonnes of fish valued at HK$34
million which accounts for about 2% of local demand for live marine fish ([3]). Some recent figures on the local marine
culture fisheries are presented in Table 5.1
Table 5.1 Marine Culture Fisheries Summary Statistics 2008-2021 (Source: AFCD)
|
AFCD
Estimate |
2009 |
2010 |
2011 |
2012 |
2013 |
2014 |
2015 |
2016 |
2017 |
2018 |
2019 |
2020 |
2021 |
|
Licensed Mariculturists |
1,050 |
1,035 |
1,010 |
1,008 |
987 |
968 |
969 |
949 |
938 |
931 |
923 |
925 |
920 |
|
Production (tonnes) |
1,437 |
1,512 |
1,185 |
1,299 |
1,005 |
1,255 |
1,219 |
1,031 |
1,004 |
850 |
889 |
687 |
332 |
|
Value (HK$ million) |
92 |
118 |
94 |
117 |
94 |
115 |
105 |
86 |
78 |
71 |
72 |
52 |
34 |
Capture fisheries is vastly
distributed in the waters of Hong Kong, the Pearl River Estuary and the
adjacent continental shelf of the South and East China Seas ([4]). AFCD reported that in 2021 an estimated
112,000 tonnes of fish was produced, which was equivalent to an economic value
of about HK$2.8 billion. Also, 10,510
local fishermen with approximately 5,170 vessels were servicing in the fishing
industry ([5]). The major fishing methods consist of
long-lining, gill-netting and purse-seining.
In 2016-17, AFCD carried out the
latest round of port survey to collect the updated data of distribution of
fishing operations and production for 2016.
According to the survey results, the highest fisheries production of 400
to 600 kg ha-1 in Hong Kong was recorded in the vicinity of the
south of Cheung Chau and Shek Kwu Chau ([6]). The highest number of fishing vessels were
distributed around Soko Islands, Shek Kwu Chau, Cheung Chau, west of Lamma,
northwest of Ninepin Island, Tap Mun and Wong Chuk Kok Tsui. Mullet (Mugilidae), sardine / shad
(Clupeidae), scad / jack (Carangidae), seabream (Sparidae), croaker
(Sciaenidae), squid, crab, rabbitfish (Siganidae), shrimp and flathead
(Platycephalidae) were the top 10 families captured in Hong Kong waters.
To promote the sustainable
development of fishing industry and to conserve fisheries resources in Hong
Kong waters, AFCD has implemented a number of fisheries management and
conservation measures. On 31 December
2012, trawling (including pair, stern, shrimp and hang trawling) was prohibited
to restore the seabed and the decreased fisheries resources ([7]). Other fisheries management practises are
implemented to supplement the ban, including:
§ Setting
up a registration system for local fishing vessels;
§ Limiting
new entrants to control the fishing effort;
§ Restricting
fishing activities of non-fishing vessels and prohibiting fishing activities of
non-local fishing vessels;
§ Designating
fisheries protection areas;
§ Habitat
enhancement and restoration (i.e. artificial reefs); and
§ Fish
restocking trials.
Since 1999, Mainland Authorities
have implemented a fishing moratorium for the South China Sea fishing
ground. In 2022, the revised fishing
moratorium has extended from 1 May to 16 August. The moratorium prohibits all fishing
operations except lining by the Hong Kong fleet outside of Hong Kong waters and
also banning on the operation of fish collectors ([8]) in order to
conserve fisheries resources and promote sustainable development of the fishing
industry ([9]).
Three FCZs are located within the Assessment Area and their
separation distances from the Project site are presented in Table 5.2. The FCZ nearest to the
Project site is Tap Mun FCZ located at ~0.3 km (by sea distance) from the
site. The other FCZs including Kau Lau
Wan and Sham Wan are located over 0.9 km away from the Project site. There are no fish ponds or oyster farms
identified in the northeastern part of Hong Kong waters (Figure
5.1).
Table 5.2 Distances between the FCZs in the Assessment Area and the Proposed FCZ at Outer Tap Mun
|
Fish Culture Zone |
Shortest Separation Sea
Distance (km) |
|
Tap Mun |
0.3 |
|
Kau Lau Wan |
0.9 |
|
Sham Wan |
2.3 |
Trawling has been banned in Hong
Kong waters since 31 December 2012. Apart
from historical data, only some published information after the trawl ban was
available for review.
The most systematic information on
commercial fishing operation and fisheries production of the Assessment Area
was obtained primarily from the AFCD Port Survey 2016/17 (Figures
5.2 to Figure
5.3). The survey was
conducted from 2015 to 2016 through a comprehensive interview survey of local
fishermen by AFCD ([10]). The survey achieved a sampling rate of about 36%
which included various fishing vessels from different homeports. Apart from the Port Survey, other recently
approved EIA and fisheries studies undertaken in the Assessment Area have also
been reviewed.
Data
from AFCD Port Survey 2016/17 indicated that the majority of vessels that operated
throughout the Assessment Area were sampans and other vessels including gill
netter, long liner, purse seine etc. were present in smaller numbers. The data indicated that the areas within and
in the vicinity of the Project site has moderate to high levels (>400-600
vessels and >600-800 vessels) of fishing operations (Figure
5.2). Moderate to high
levels of fishing operation (>400-600 vessels and >600-800 vessels) were
recorded in other areas around the coastline of Hoi Ha Wan, Tolo Harbour, Port
Island and Tap Mun. Areas within Hoi Ha
Wan Marine Park (HHWMP) supported moderate to high levels of fisheries
operation respectively (>400-600 vessels for HHWMP areas). Under the Marine Parks and Marine Reserves
(Amendment) Regulation 2019 which came into effect on 1 April 2020, commercial
fishing would be banned and eventually phase out in HHWMP to protect coral
communities and enhance the overall fisheries resources in Hong Kong ([11]). A
transitional period of two years is provided under the ban which new fishing
permits will no longer be granted and existing fishing permits will not be
renewed for HHWMP.
Fisheries production of the
Assessment Area in terms of weight as reported in the AFCD Port Survey 2016/17
is presented in Figure
5.3. Results showed that
fisheries production within and in the vicinity of the Project site is moderate
(>200-300 kg/ha), with low level of fisheries production recorded at the
northeastern waters of Port Island (>100-200 kg/ha) and in the majority of
Long Harbour (>50-200 kg/ha). Low
level of fisheries production (>0-50 kg/ha) was noted at offshore areas of
northeastern waters.
Historically, Tolo Harbour was
found to consist of fish assemblages of moderate species richness with low
diversity identified ([12]). It was recorded that the majority of fish
assemblages was fast growing but with low commercial value thriving in heavily
eutrophic waters. The species captured that were considered
of medium commercial value were sea breams, rock fish and chicken grunt ([13]). Low diversity and species evenness were
recorded at Long Harbour which corresponded to the location of the Project site
and the lowest species evenness was recorded at north-west Mirs Bay which was
attributed to the majority of the catch consisting of Ponyfish (Leiognathus brevirostris) ([14]).
A more
recent review of the fisheries resources data could be referred to the
monitoring of local fisheries resources from 2010-2015 initiated by AFCD with
the implementation of the trawl ban in 2012.
Demersal fisheries surveys were conducted using stern and shrimp
trawlers across four areas in Hong Kong waters and the results showed that
there were signs of recovery of fisheries resources. In the northeastern waters relevant to this
Assessment Area, it was reported that the abundance and biomass of seabreams
(Sparidae) and hairtails (Trichiuridae), and the abundance of threadfin breams
(Nemipteridae) had increased ([15]). The main commercial fisheries resources
(ranked based on the biomass of each family) found in the northeastern waters
of Hong Kong ([16])
are summarised in Table 5.3 below. Overall, the northeastern waters generally
supported fish families of low commercial value, such as Ponyfish (Leiognathus sp.), with some commercially important families recorded in the area,
such as swimming crabs (Portunidae), seabreams (Sparidae), flatheads
(Platycephalidae) of lower biomass ranking.
A study on Marine Parks and Marine
Reserve fisheries resources in 2016 showed that the abundant fishes in HHWMP included
both fishes of low and high commercial values ([17]). The most abundant species in HHWMP were
pearl-spotted spinefoot (Siganus
canaliculatus) and jarbua terapon (Terapon
jarbua) respectively which were of low commercial values. Other abundant species in HHWMP included
rice-paddy eel (Pisodonophis boro),
Japanese golden thread (Nemipterus
japonicas), red pargo (Pagrus major),
threadfin porgy (Evynnis cardinalis)
and black bream (Acanthopagrus schlegelii). Among the abundant species, Japanese golden thread,
red pargo and black bream were commercially important. It should be noted that HHWMP is some
distances from the project site (~0.8 km).
Table 5.3 Main Commercial Families of Fisheries Resources in Northeastern Hong Kong Waters from Fishery Surveys (Source: AFCD Hong Kong Fisheries Resources Monitoring Report (2010-2015))
|
Rank |
Main Commercial Families
from Shrimp Trawl Surveys |
Main Commercial Families
from Stern Trawl Surveys |
Main Commercial Families
from Purse-Seine Surveys |
|
1 |
Leiognathidae |
Leiognathidae |
Clupeidae |
|
2 |
Platycephalidae |
Clupeidae |
Carangidae |
|
3 |
Portunidae |
Sparidae |
Engraulidae |
|
4 |
Clupeidae |
Carangidae |
Scombridae |
|
5 |
Sparidae |
Polynemidae |
Sphyraenidae |
|
6 |
Gerreidae |
Trichiuridae |
|
|
7 |
Synodontidae |
Siganidae |
|
|
8 |
Squillidae |
Synodontidae |
|
|
9 |
Sciaenidae |
Sciaenidae |
|
|
10 |
Soleidae |
Nemipteridae |
The northeastern Hong Kong waters were previously identified
in 1998 as fisheries spawning grounds for various fish species ([18]). In Hong Kong, spawning period differs
among fisheries species with the majority of commercial species aggregate and
spawn in the open waters during June to September. Some fish species, including flathead (Platycephalus
indicus) and shad (Clupanodon (Konosirus) punctatus), spawn in late
winter / early spring (i.e. February to April) and a few are known to spawn in
January. Shrimp scad (Alepes djedaba)
spawns in early summer (around June) whilst pony fish (Leiognathus
brevirostris) and croakers were found to be reproductive throughout most of
the year from May to December. The
spawning period of most of the crustacean species was found to be from April to
November, with spawning concentrated between June and August.
Field surveys
were conducted in Tolo Channel and Long Harbour from May 2016 to May 2017 to
investigate the abundance, composition and distribution of the ichthyoplankton,
zooplankton, juvenile fish and crustacean ([19]). The study recognised the areas as spawning
ground and nursery area which supported a diverse assemblage of fisheries
resource. The ichthyoplanktons of
several commercially important species, such as rockfish
(Sebastiscus marmoratus), seabreams (Acanthopagrus schlegelii, Sparidae
spp.), grunt (Parapristipoma trilineatum), shad (Nematolosa
japonica) and flatheads (Inegocia japonica, Platycephalus indicus),
were recorded in the surveys.
The recognised spawning ground in
northeastern Hong Kong waters is approximately >7 km long covering waters
from the north of Kat O to Wong Chuk Kok Hoi (Figure
5.1). The Project site is
located at ~4 km away from this recognised spawning ground of the northeastern
waters (Figure
5.1).
The waters in Tolo Channel and
northeastern Mirs Bay was identified as important nursery areas for high
commercial value species in 1998, which extends approximately 10 km from Yan
Chau Tong Marine Park (YCTMP), covering waters at Tolo Harbour, Tap Mun, Port
Island and Long Habour (Figure
5.1). This recognised
nursery area is an important habitat for commercial species, namely red pargo (Pagrus major) and the goldlined seabream
(Rhabdosargus sarba) ([20]). The fish fry of Pagrus major have been found to be most abundant during February
and March, whereas juveniles of other commercial species were found abundantly
from July to August. A juvenile fish
survey conducted between 2013 and 2014 identified the mangrove and seagrass bed
in YCTMP as important nursery areas, but the dominant species, such as bald
glassy (Ambassis gymnocephalus), are
of low commercial value ([21]). The Project site is located within this
recognised nursery area (Figure
5.1).
As mentioned in Section
5.3.2.4, Tolo Channel and Long Harbour were also recognised by a study
conducted between 2016 and 2017 as nursery area which supported a diverse
assemblage of fisheries resource ([22]),
with some commercially important families such barracuda (Sphyraena flavicauda), jack mackerel (Trachurus japonicus), rabbitfish (Siganus fuscescens) and seabreams (Acanthopagrus schlegelii, Rhabdosargus
sarba, Evynnis cardinalis, Pagrus major) were recorded in the area ([23]).
An Artificial Reef (AR) program has
been implemented in Hong Kong’s waters by AFCD since 1996 as an effort to
enhance fisheries resource whilst promoting biodiversity ([24]). ARs are recognised worldwide as having the
ability to encourage growth and development of a great number and variety of
marine organisms, which in turn provide food, shelter and protection for
fishes. Therefore, the ARs are
considered to be fisheries sensitive receivers.
There has been a total of 673 units of ARs with a total volume of over
179,200 m3 ([25])
deployed in Hong Kong waters, the location of all ARs deployed is
recorded by the Hong Kong Artificial Reef Project.
There are two AR deployment sites
within the Assessment Area, including HHWMP and Long Harbour (Figure
5.1). No AR has been
deployed within the Project site. The
nearest AR from the Project site would be those deployed at Long Harbour (~0.7
km south of the Project site), followed by those deployed at HHWMP (~0.8 km
west of the Project site). A total of 6
and 7 units of ARs with a total volume of 33,420 m3 and 9,530 m3
ARs were deployed in Long Harbour from 2002-2004 and in HHWMP from 1998-2003
respectively, to provide hard, bottom, high profile habitat in areas
without natural cover and act as biofilters to enhance habitat quality and
marine resources ([26]).
Based
on the baseline information reviewed, moderate to high levels of fishing
operation with moderate level of fisheries production were reported at the
Project site, and similar levels of fisheries operation and production were
also reported elsewhere in the broad Assessment Area, which indicates the
Project site does not represent a unique fishing ground. The Assessment Area including the Project
site also supported fisheries resources that are mainly with low commercial
value, and areas that support fisheries of higher commercial values, such as
HHWMP (~0.8 km west of the Project site), are located at some distances from
the Project site. ARs which are key
fisheries habitats are also at some distances (>0.7 km from the Project
site) from the Project site.
Annex
9 of the EIAO-TM
states that spawning ground and nursery area can be regarded as important
habitats to fisheries. The Project site
is located within the recognised nursery area in northeastern Hong Kong waters
which covers a large area of over 10 km long, but is located ~4 km away from
the recognised spawning ground.
Consequently the Project Site only occupies a very small proportion of
the nursery area. The potential for the
Project site and its immediate vicinity to function as a unique spawning ground
and nursery area is relatively low.
Based on the preceding review of
the available information on the capture and culture fisheries of the waters in
the vicinity of the proposed Project, the potential sensitive receivers that
may be affected by the Project activities (i.e.
distances are shown by sea distance) are identified as follows:
§ Recognised
nursery area of commercial fisheries resources in northeastern waters which is
located within the Project site;
§ Recognised
spawning ground of commercial fisheries resources in northeastern waters which
is ~4 km from the Project site;
§ FCZ
at Tap Mun (located at ~0.3 km east of Project site), Kau Lau Wan (located at
~0.9 km southeast of Project site) and Sham Wan (located at ~2.3 km south of
Project site);
§ A
total of 33,420 m3 ARs were deployed in Long Harbour (located at
~0.7 km south of the Project site); and
§ Hoi
Ha Wan Marine Park (located at ~ 0.8 km west of the Project site) and 9,530 m3
of ARs deployed within.
The locations of the sensitive
receivers are shown in Figure
5.1.
A review of baseline fisheries
conditions from available literature was conducted for the purpose of
establishing the fisheries importance of the waters in the Assessment Area and
its vicinity. Information
from the water quality impact assessment has been examined to assess
potentially affected area by perturbations to water quality parameters.
The potential impacts due to the
construction and operation of the Project were then identified and evaluated
(with reference to the EIAO-TM Annex 17
guidelines and the criteria in EIAO-TM
Annex 9).
The construction of the proposed
Project will mainly involve the setup of fish farm structures, including fish rafts
/ cages, auxiliary facilities and mooring system. No dredging works is required during the
construction phase.
The scale of construction work
on-site is relatively small. Main
components of the rafts / cages are manufactured off-site and will be towed to
the Project site using tug boat. On-site
assembly and anchoring of the fish rafts / cages will be assisted by a small
number of marine vessels such as sampans and small speed boats for up to a few
trips per day. Anchoring of these
vessels might be required. No heavy
construction plant would be used. Fish
rafts / cages and auxiliary facilities, such as storage space and shelters,
would be positioned by anchor lines attaching to the anchorage points on the
seabed. Use of winch might be required
during the assembly and anchorage of fish rafts / cages. All construction activities shall be
conducted during daylight hours.
Potential impacts to fisheries
resources and fishing operations arising from these works may be divided into
those related to:
§ Disturbances
of fisheries habitat (including spawning ground and nursery area) and loss of
access to fishing grounds; and
§ Underwater
sound from marine construction activities and marine vessels.
Direct impacts to
fisheries resources, habitats (including nursery area) and fishing operations
include disturbance caused by assembly and installation activities
on-site. The installation of fish farm structures are expected to be completed
within a few weeks for each fish raft, and would cause temporary
disturbance to fisheries habitat and loss of access to potential fishing
grounds with an area of approximately 55 ha.
Fish farm structures, such as fish cages will occupy a section of the
water column and the disturbance of seabed due to the anchorage of fish farm
structures will be confined to a thin surface
layer (<0.5 m) within a small area.
It should be noted that only a small number of vessels will be used and
the frequency / trip of these vessels would also be relatively low. No disturbance to the identified fisheries
sensitive receivers, including Tap Mun FCZ (~0.3 km from the Project site), Kau Lau Wan FCZ (~0.9 km
from the Project site), Sham Wan FCZ (~2.3 km from the Project site), and
ARs of Long Harbour and HHWMP (~0.7 km and ~0.8 km from the Project site
respectively) is expected.
In the
context of the size of fisheries habitats and fishing ground available in the
vicinity, the size of the area affected would be small. Considering the
temporary nature of the disturbance (a few weeks for each fish raft / cage),
impacts are considered to be of minor significance and unacceptable impacts on
fisheries resources, habitats and fishing activities are not expected. Fisheries resources are
expected to return to the area following the cessation of fish farm
construction activities.
Construction
activities, such as during the assembly of fish raft, would generate noise,
glare and dust which may affect fisheries resources. Potential impacts, mostly to fish species,
would have temporary avoidance of areas in the vicinity of works area or close
to the source of disturbance.
Considering the temporary nature of the construction works, impacts from
the generation of noise, glare and dust on fisheries habitats are considered
negligible, and unacceptable impacts on the fisheries resources are not
anticipated. Major lighting sources will
be pointed inward and downwards to avoid disturbance to wildlife, unacceptable
impacts on the fisheries resources are not anticipated.
Intermittent sounds, which occur during assembly
and installation activities on-site and marine vessel movement, may have an impact on
fisheries resources. Potential effects
of increased underwater sound include physiological stress, avoidance and
injury (at high pressure levels). The
level of impact is however dependent upon background sound, number and type of
species affected, proximity of organism to the sound source, attenuation
properties of seabed sediments and hearing capabilities of the species
affected, etc..
Most marine invertebrates do not possess air-filled space
and thus it is generally considered that sound would have limited physiological
or behavioural effects on marine invertebrates, except if they are located within
a few metres of the sound source.
Therefore, underwater sound generated from marine works is expected to
have negligible impact on marine invertebrates in the Assessment Area.
The impact of underwater sound generation from
construction activities on fish is highly depended upon the hearing
capabilities of the different species present in the area, with the hearing
specialists being of greatest concern.
The significance of these effects is dependent upon the proximity of
fish to the sound source. Considering
that a small number of marine vessels would be present temporarily at the
Project site during fish farm construction, fish species that are sensitive to
the generation of sound are likely to instinctively avoid the area once works
commence and would be temporarily displaced to other areas where similar
habitat conditions are present.
Fisheries
resources are expected to return to the area following the cessation of fish
farm construction activities.
Waters within the Assessment Area
and its vicinity is subject to moderate to high levels of marine traffic by
similar types of vessels. It is
reasonable to assume that fish are habituated to a moderate to high background
levels of underwater sound, and a small increase in vessel activity associated with the
construction of this Project is not anticipated to result in unacceptable
impacts on fisheries resources. Overall,
the fisheries sensitive receivers, including Tap Mun FCZ (~0.3 km from the Project site), Kau Lau Wan FCZ (~0.9 km
from the Project site), Sham Wan FCZ (~2.3 km from the Project site), and ARs of Long Harbour and HHWMP (~0.7 km and ~0.8 km from the
Project site respectively), are located at some distances from the Project site
and unacceptable impacts on these fisheries sensitive receivers are not
expected.
Mariculture activities, such as
management of fish raft / cages and fish stocks within the Project site will be
undertaken during operational phase.
Limited numbers of small power generators will be used on fish rafts to
support daily mariculture activities.
The transportation of fish stocks, fish feed, fish raft equipment and
workforce as well as occasional visitors will make use of small marine vessels
such as sampans and speed boats for a few trips a day. No maintenance dredging or sediment removal
is anticipated during FCZ operation. All
operation activities shall be conducted during daylight hours. The potential impacts on fisheries of the
Assessment Area include:
§ Changes
in fisheries habitats and loss of access to fishing grounds;
§ Temporary
relocation of rafts under typhoons or algal blooms;
§ Underwater
sound from daily operations and marine vessels;
§ Perturbations
to key water quality parameters during fish farm operation, including fish feed
wastage and fish excretion; and
§ Fish
diseases.
As
discussed in Section 5.5.1.1, the fish farm structures will not fully occupy
all of the Project site area but mainly a section of the water column and a
small area of seabed confined to a thin surface
layer (<0.5 m). In the
context of the size of fisheries habitats and fishing
ground available in the vicinity, the size of the area affected would be small and the majority of fisheries
resources found in and around the vicinity of the Project site are of low
commercial value. The impacts on
fisheries resources and fisheries habitat are considered to be of minor
significance and unacceptable impacts are not expected.
Fish farm
structures would provide hard substrate that could be colonised by a variety of
marine organisms. Although periodic
cleaning will be implemented as part of the fish farm management practice to
maintain good aquaculture environment, regular cleaning activities will be
mainly applied to fish cages / nets, while the majority of the fish farm
structures, such as the main framework of the fish raft, auxiliary facilities
and mooring system will remain intact most of the time. There is considerable knowledge in Hong Kong
and elsewhere on the colonisation of marine structures with species such as
seaweeds, crustaceans, octocorals, bivalves, amphipods, anemones, bryozoans and
more mobile fauna including crabs.
Colonisation of these structures could attract fish and marine
invertebrates into the area. Overall,
the structures of the fish farm are expected to result in potential positive
effect on fisheries resources and habitats of the waters within and in the
vicinity of the Project site.
All the
fish rafts / cages will be floating with permeable nets to allow water
exchanges with the marine environment.
Consequently, it is predicted that no unacceptable changes in
hydrodynamics will occur.
The impact from the construction works on fishing
activity is of temporary nature.
Furthermore, although the project site is largely located in an area
with high level of fishing activities, the loss of access to fishing ground is
considered to be relatively small compared to the availability of fishing
grounds elsewhere in northeastern Hong Kong waters available for fishing
activities. Overall, the impacts on
fishing activity are of minor significance and no unacceptable impacts are
expected.
Operational activities, such as cleaning of fish cages
and the use of lighting, would generate noise, glare and dust which may affect
fisheries resources. Potential impact,
mostly to fish species, would have temporary avoidance of areas in the vicinity
of the operational area or close to the source of disturbance. Considering the temporary nature of the
cleaning activities, impacts from the generation of noise, glare and dust on
fisheries resources are considered negligible, and unacceptable impacts on the
fisheries resources are not anticipated.
Major lighting sources will be pointed inward and downwards to avoid
disturbance to wildlife, unacceptable impacts on the fisheries resources are
not anticipated.
In
general, relocation of fish rafts adopting advanced mariculture technologies are
not necessary under adverse weather (e.g. typhoon) given the framework of fish
cages would use weather-resistant and durable materials (e.g. HDPE cages, steel
truss cages). For other potential
circumstances (e.g. red tide event, outbreak of fish disease), the licensees
will review the need of fish raft relocation and propose the fish raft
relocation plan as necessary for agreement with AFCD on a case-by-case basis,
depending on the type of algal bloom (any toxicity to fish), expected duration
of such circumstances, feasibility for early harvesting of fish stock,
feasibility of implementing onsite control measures etc. In case fish raft relocation is considered
necessary, the fish rafts will be relocated away from the areas of
circumstances, avoid marine fairways and utilities and at some distance away
from ecological and fisheries sensitive receivers (e.g. about 200 m away from
established coral communities) to minimise potential impacts to these sensitive
receivers. Such relocation will be
temporary (e.g. a few weeks) and the fish rafts will return to the Project site
upon the cease of the circumstances. The
mobilisation of the fish rafts will cause temporary disturbance to fisheries
habitat. Increased operation of marine
vessels will occur due to the towing of fish rafts to the new location, and the
re-anchoring of fish rafts will cause temporary disturbance to the water column
and seabed. The corresponding impacts
would be similar to those occurred in the construction phase (Section
5.5.1). Overall, impacts are considered to be of minor significance and unacceptable
impacts on fisheries resources, habitats and fishing activities are not
expected.
Operation of the fish farm would produce underwater sound
from the management of fish rafts / cages and fish stocks, and operation of
marine vessels. The daily operations of
small marine vessels, such as sampans or speed boats would be temporary which
the underwater sound characteristics of these vessels are similar to the
operations at Tap Mun FCZ and marine traffic at the ferry routes nearby. Fish in these waters are habituated to the
background level of underwater sound, and a small increase in mariculture and
vessel activities associated with the operation of this Project are not anticipated
to result in unacceptable impacts on fisheries.
Mariculture activities would
result in an increase in water quality pollutants primarily
from fish feed, feed wastage, fish excretion and dead fish. The increase in pollution load would affect the water quality in the receiving waters and the potential impacts on fisheries are as follows:
§ Suspended
solids (SS) dispersion;
§ Dissolved
oxygen (DO) depletion; and
§ Elevated
nutrient levels.
The use and storage of chemicals, such
as pharmaceuticals for fish and those used for equipment maintenance will be
limited on site and stored at secured locations, discharge of water containing
such chemicals is not expected from daily operations. Human activities, such as the removal of
fouling organisms on fish net / cages and the generation of sewage by the staff
on site will be limited. The dislodged
biomass will not be constituted as additional pollution load by feeding on the original
pollution source at the fish farm, and automated / remote operation of
mariculture activities is expected for the new FCZ with minimal manual labour
required. Water quality impacts as a
result from chemical and sewage discharge from the Project site are therefore
not anticipated, and mainly impacts from fish feed, feed wastage, fish
excretion and dead fish are discussed below.
To estimate the impacts on fisheries sensitive
receivers of the Assessment Area, computer modelling of changes in water quality were conducted under two scenarios:
§ Baseline
scenario, which covered the “without-project” condition in 2023, including pollution loading from existing FCZs (including Tap Mun FCZ (~0.3 km from the Project site), Kau Lau Wan FCZ (~0.9 km
from the Project site) and Sham Wan FCZ (~2.3 km from the Project site)); and
§ Project
scenario, which took into account the additional pollution load from the
mariculture activities at the Project site, as well as the other nearby
proposed new fish culture zones at Wong Chuk Kok Hoi and Mirs Bay (each at their
carrying capacity).
Relevant assessment criteria, i.e. Water Quality
Objectives (WQOs) in the Mirs Bay and Tolo Harbour and Channel WCZs, were then
used to assess potential impacts on fisheries.
Fish farm operation are expected to generate SS within
the water column as a result of fish feed, fish feed wastage and fish
excretion, contributing to an increase in sediment deposition in close
proximity of the Project site.
Fluxes of SS naturally occur in the marine environment
and as a result, fish have evolved behavioural adaptations to tolerate changes
in SS load (e.g. clearing their gills by flushing water over them). Beyond the Project site, dispersion will
cause a rapid decrease in the suspended solids concentrations. Compared to adult fish, larvae and
post-juvenile fish are relatively more susceptible to variations in SS
concentrations as their sensory system is less developed. Adult fish are more likely to move away from
area of disturbance when they detect sufficiently elevated SS concentrations
and therefore are unlikely to be significantly impacted.
The SS level at which fish move into clearer water is
defined as the tolerance threshold which varies among species and different
stages of the life cycle. If SS levels exceed
tolerance thresholds and the fish are not able to move away from the affected
area, the fish are likely to become stressed, injured and may eventually
die. The rate, timing and duration of SS
elevations influence the type and extent of impacts upon fish and potentially
crustaceans.
Findings from literature reviews indicated that lethal
responses had not been reported in adult fish at SS values below 125 mg/L ([27])
and that sub-lethal effects were only observed when levels exceeded 90
mg/L ([28]). However, as part of a study for AFCD, Consultancy Study on Fisheries and Marine
Ecological Criteria for Impact Assessment guideline values have been
identified for fisheries and selected marine ecological sensitive receivers
based on international marine water quality guidelines for the protection of
ecosystems ([29]). The AFCD study recommends a maximum SS
concentration of 50 mg/L (based on half of the no observable effect
concentrations). However, the study
cautioned that site-specific data should be considered in environmental
assessments on a case-by-case basis. In
order to provide a more conservative assessment (i.e. with a lower tolerance
criterion), the relevant WQOs for SS elevation are adopted instead in this
study as the assessment criteria for fisheries sensitive receivers.
The water quality modelling results have indicated
that at all fisheries sensitive receivers, SS elevations as a result of fish
farm operation are predicted to be compliant with the relevant WQOs for both
wet and dry seasons. SS elevations are
expected to be temporary in nature and localised to the Project site. With the fish farm standing stock kept within
the Project site’s maximum carrying capacity and the use of pellet feed within
fish farms, potential impacts to fisheries will be well managed. Although the Project site is located within
the recognised nursery area in northeastern Hong Kong waters, the Project site
only occupies a very small proportion of the habitat and generally supported
fish families of low commercial value. Areas which supported fisheries of higher
commercial value, such as YCTMP and HHWMP which are at some distance away from
the Project site. As such, unacceptable
impacts from fish farm operation on fisheries resources and habitats (including
spawning ground or nursery area) due to potential elevations of SS are not
expected to occur.
The relationships between SS and DO are complex, with
elevated SS in the water column together with a number of other factors to
reduce DO concentrations. Elevated SS
(and turbidity) reduces light penetration, lowers the rate of photosynthesis by
phytoplankton (i.e. primary productivity) and thus lowers the rate of oxygen
production in the water column.
Furthermore, the decomposition of organic matter in fish feed, fish
excretion and dead fish in the water column may consume DO in the receiving
waters. The resulting overall DO
depletion has the potential to cause an adverse effect on the eggs and larvae
of fish and crustaceans, as at these stages of development high levels of
oxygen in the water are required for growth to support high metabolic growth
rates.
The water quality modelling results have indicated that DO
depletion associated with fish farm operation are predicted to be low and
remain compliant with the relevant WQO DO criteria at most fisheries sensitive
receivers. Lower DO levels recorded at
the northern areas are likely a result of relatively high pollution loading
from dry weather load and treated sewage effluent from the Starling Inlet (also
known as Sha Tau Kok Hoi), as well as pollution load from Yantian area of
Guangdong. Within the Long Harbour
embayment, the levels of dissolved oxygen were predicted to remain rather
stable with and without project operation.
The mariculture operation at the Project site and other proposed FCZs
would result in limited change in dissolved oxygen and the predicted dissolved
oxygen level would comply with the corresponding WQO criterion. Outside of the Long
Harbour embayment, no unacceptable change in DO level is predicted at other
fisheries sensitive receivers in both baseline and project scenarios.
Overall, there is limited change in
the predicted DO levels at baseline and project scenarios
and unacceptable impacts to fisheries are not expected to occur.
High levels of nutrients released from fish feeds,
fish excretion and dead fish to the water column may potentially cause rapid
increases in phytoplankton population, on occasions to the point that an algal
bloom occurs. An intense bloom of algae can lead to sharp decreases
in the levels of DO. This decrease will initially occur in the
surface water, and then spread to deeper waters as dead algae fall through the
water column and decompose on the seabed. Anoxic conditions may
result if DO concentrations are already low or are not
replenished. As discussed above, reduced levels of DO can impact the
eggs and larvae of fish and crustaceans which require high levels of oxygen for
development. Significantly low levels of DO may also result in fish
mortality.
The water quality modelling results have indicated
that the levels of nutrients as a result of fish farm operation are expected to
be low in general within the Assessment Area.
Predicted levels of Total Inorganic Nitrogen (TIN) and unionized ammonia
at the Project site and all fisheries sensitive receivers are below the
corresponding assessment criterion.
Overall, the increased levels of nutrients in the water column as a
result of fish farm operation are considered to be of minor significance and
unacceptable impacts to fisheries are not expected to occur.
Chlorophyll-a is a
photosynthetic pigment of phytoplankton and is commonly used as a direct
indicator of algal biomass. As mentioned
above, increased levels of phytoplankton due to nutrients released from fish
farms could potentially trigger algal blooms, in which could reduce DO levels
in the water column and result in fish mortality.
The water quality modelling
results have indicated that the levels of chlorophyll-a vary spatially across
the Assessment Area and are generally higher at the surface level and areas
with shallower water depth. The
predicted change of chlorophyll-a levels between baseline and project scenarios
at the Project site and all other fisheries sensitive receivers within the
Assessment Area is limited and below the corresponding assessment
criterion. Therefore, fish farm
operation is not expected to result in significant increase of chlorophyll-a
and unacceptable impacts to fisheries are not expected to occur.
Fishes are kept in close proximity
at individual cages in fish farms compared to the open marine waters which will
increase the chance of disease transmission once developed.
It is expected that good mariculture practices shall be
implemented by the fish farmers and preventive measures such as quarantine
newly stocked fish / fry, using uncontaminated fish feed, regular monitoring
and control of fish density, etc., as specified in Appendix 2A. As mentioned in Section 5.5.2.4, if the use of pharmaceuticals for fish is required, it will be limited on
site and stored at secured locations, discharge of such chemicals is not
expected from daily operations. Mariculturists at the Project site would be required to strictly observe
the requirement under Cap. 529 Veterinary Surgeons Registration Ordinance and
have strict control on prescription drugs, therefore, adverse impacts on
fisheries are not anticipated. The implementation of the fish health
surveillance program would also be vital to maintain the health of these
maricultured fish species in the new FCZ ([30]), therefore, AFCD has implemented the
Fish Health Inspection Programme by conducting regular visits to fish farms, to
identify early outbreaks of fish diseases and advice on good mariculture
practices and prevention measures to fish farmers as specified in Appendix 2A ([31]).
Unacceptable impacts on fisheries are expected to be minor.
From the information
presented above, the fisheries impacts associated with the Project are not
considered to be significant. An
evaluation of the impacts according to Annex
9 of the EIAO-TM is presented in Table 5.4.
Table 5.4 Evaluation of Fisheries Impacts in accordance with the Criteria described in Annex 9 of the EIAO-TM
|
Potential Impact |
Nature of Impact |
Size of Affected Area |
Loss of Fisheries Resources / Production |
Destruction and Disturbance of Nursery and
Spawning Grounds |
Impact on Fishing Activity |
Impact on Aquaculture Activity |
Overall Impact Significance |
Mitigation Measures Required |
|
Construction Phase |
||||||||
|
Habitat
disturbances and loss of access to fishing grounds |
Temporary and short term (a few weeks) in the active
works area. |
Loss of access to fishing grounds would cover the whole Project site
(55 ha). |
Project site is
of moderate levels of fisheries production and the majority of fisheries resources is of low commercial value. Considering that
the impacts are temporary, impacts on
fisheries resources / production is minor. |
The Project site is located within the recognised
nursery area with the spawning grounds located ~4 km away. No destructive
constructing method are used. The magnitude of disturbance is considered to
be low. |
Moderate to high
fishing operations have been recorded at the Project site. Considering the
temporary nature of construction impact, overall, the impacts on fishing
activity are considered to be of minor significance and no unacceptable
impacts are expected. |
No adverse impact
is expected on Tap Mun FCZ, Kau Lau Wan FCZ and Sham Wan FCZ located at ~0.3
km, ~0.9 km and ~2.3 km from Project site respectively. |
Minor |
No |
|
Underwater sound
from marine construction activities and marine vessels |
Temporary and short term (a few weeks) in the
active works area. |
Localised to sound-generating activities, e.g. assembly
of fish rafts, installation of mooring system, marine vessels. |
Avoidance and habituation by fish are
expected. Loss of fisheries resources
or production are considered negligible. |
Underwater sound
is expected to have negligible impact on spawning ground and nursery area. |
Underwater sound
is expected to have negligible impact on fishing operations. |
No adverse impact
is expected on Tap Mun FCZ, Kau Lau Wan FCZ and Sham Wan FCZ located at ~0.3
km, ~0.9 km and ~2.3 km from Project site respectively. |
Minor |
No |
|
Operation Phase |
||||||||
|
Change in fisheries habitat and loss of access to fishing grounds |
Long term over
Project operation but reversible. |
Loss of access to fishing grounds would cover the whole Project site
(55 ha). |
The fish farm structures only occupy a
section of the water column and a small area of seabed confined to a thin
surface layer. Considering that the majority of fisheries resources is of low
commercial value in the Project site, impacts on fisheries resources /
production is minor. Potential positive effect on fisheries resources due to
the colonisation of marine organisms on fish farm structures is expected. |
The fish farm structures only occupy a section of
the water column and a small area of seabed confined to a thin surface layer,
impacts were considered of minor significance. Fish farm structures may
potentially provide spawning and nursery habitats, the magnitude of
disturbance is therefore considered to be low. |
The loss of access to fishing ground is also
considered to be small compared to the availability of fishing grounds
elsewhere in northeastern Hong Kong waters available for fishing activities. Suitable fishing grounds outside of these
structures can allow similar fishing activities to take place. Overall, the
impacts on fishing activity are of minor significance and no unacceptable
impacts are expected. |
No adverse impact
is expected on Tap Mun FCZ, Kau Lau Wan FCZ and Sham Wan FCZ located at ~0.3
km, ~0.9 km and ~2.3 km from Project site respectively. The proposed FCZs would provide more fisheries
resources to the local and global fisheries market. |
Minor |
No |
|
Temporary relocation of fish rafts/ cages |
Temporary. |
Localised to the immediate vicinity of the area
of fish rafts / cages relocation. |
Avoidance by fish is expected, and negligible
loss of fisheries resources when re-anchoring occurs. |
Impacts are localised with neglgible impact on
nursery and spawning grounds when re-anchoring occurs. |
Impacts are localised with negligible impact on
fishing operations when re-anchoring occurs. |
Impact is variable depending on the location in
which the fish rafts / cages will be relocated (i.e. distance with other
existing FCZs). Considering that the impact is temporary and the
rafts / cages shall be relocated back into the Project site afterwards,
impacts are localised with negligible or low impact. |
Minor |
No |
|
Underwater sound from marine vessels and daily
operations |
Long term over
Project operation but reversible. |
Localised to the
immediate vicinity of the sound-generating activities e.g. maintenance of the
fish rafts / cages and marine vessel movement. |
Avoidance and
habituation of fish is expected. Loss of fisheries resources or production
are considered negligible. |
Underwater sound is expected to have negligible
impact on spawning ground and nursery area. |
Underwater sound is expected to have negligible
impact on fishing operations. |
Daily fish farm
operations and marine traffic are present at the Tap Mun FCZ and nearby ferry
routes. Small increase of underwater
sound from the Project site is expected to have no unacceptable impact. |
Minor |
No |
|
Changes in water quality due to fish farm
operational activities |
Long term over
Project operation but reversible. |
Localised to the immediate
vicinity of the fish farm. |
Water quality compliance expected with no
unacceptable impact. |
Water quality compliance expected with no
unacceptable impact. |
Impacts are localised with negligible
impact on fishing operations. |
No unacceptable water quality impact
expected at FCZs. |
Minor |
Water quality mitigation measures would further
reduce impacts. |
|
Fish diseases |
Infrequent
outbreaks. Occur when source of pathogens / stressors are present. |
Specific fish
rafts / cages or waters in the vicinity of the Project site. |
Magnitude of
impact would depend on the type of disease induced. Proper treatment will be implemented at the
infected sites, therefore the magnitude of impact is considered to be low. |
Magnitude of
impact would depend on the type of disease induced. Proper treatment will be implemented at the
infected sites, therefore
the magnitude of impact is considered to be low. |
Impacts are localised with negligible impact on fishing operations. |
Good mariculture practices will be implemented, therefore,
impact on fish stock will be minor. |
Minor |
No |
As there are no other existing or
committed non-FCZ projects identified in the vicinity of the Project site, the Water Quality Impact Assessment
conducted is based on the worst-case scenarios of concurrent operation of all
existing and planned FCZs as sources of pollution. It is expected that all FCZs will be operated
within the maximum carrying capacity and therefore, unacceptable impacts to
water quality are not anticipated.
Consequently, unacceptable cumulative impacts to fisheries resources are
not predicted to occur.
Potential operational impacts presented in Section
5.5.2 were examined to evaluate potential cumulative impacts with other
operations / developments in the northeastern Hong Kong waters. Outcomes of this evaluation, excluding the
impact on water quality are summarised as follows:
§ Changes
in Water Quality: No marine
works or other major source of pollution is expected from the construction
phase of the Project, therefore, no unacceptable cumulative impact during the
construction phase is expected. Water
quality modelling results for the operation phase, including the pollution
loading from existing and other proposed FCZs (i.e. Wong Chuk Kok Hoi FCZ and
Mirs Bay FCZ) also showed that no unacceptable cumulative impact during the
operation phase is expected.
§ Underwater
Sound: This Project is located at ~0.3 km and 0.9 km away
from Tap Mun FCZ and Kau Lau Wan FCZ respectively, and >2 km away from other
existing and planned FCZs. For this
Project, mainly small marine vessels e.g. sampans and speed boats operated by
fishermen would be used during FCZ operation.
The underwater acoustic profiles generated by works vessels of this
Project would therefore be similar to the daily operations of the Tap Mun FCZ
and other nearby FCZs and ferry routes.
Cumulative effects of works vessels operational sound, if any, are
anticipated to be negligible. It is not
expected to result in significant cumulative impact to the fisheries resources
within the Assessment Area.
§ Marine
Traffic: This Project is located at sufficient distance from
other FCZs in the vicinity. It is
expected to involve a relatively small number of small marine vessels, such as
sampans and speed boats that travel to and from the Project site during daily operations. Given that existing marine traffic is present
within Outer Tap Mun near Tap Mun FCZ and Tap Mun pier and that the waters off
northeastern Hong Kong have moderate levels of existing marine traffic, such as
the ferry route between Ma Liu Shui to Lai Chi Wo / Kat O and Ma Liu Shui to
Tap Mun, the cumulative effects of marine traffic disturbance to the nearby
fishing operations are anticipated to be negligible.
In accordance with the guidelines
in the EIAO-TM on fisheries impact assessment, the approach adopted in
this EIA includes:
§ 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 confining works in specific area or season; and
§ Compensation:
When all possible mitigation measures have been exhausted and there are still
significant residual impacts or when the impacts are permanent and
irreversible, consideration shall be given to off-site compensation. It may include enhancement of fisheries
resources and habitats elsewhere.
To summarise, this assessment of
impacts demonstrates that impacts will largely be avoided and minimised during
the construction and operation of the proposed Project, particularly to the key
fisheries sensitive receivers, such as the spawning ground and nursery area of
the northeastern waters of Hong Kong, marine parks, ARs and nearby FCZs.
Impacts to fisheries have largely
been avoided and minimised through proper planning and design of the
works. The Project site is selected to
be far from HHWMP and ARs, such that impact to these habitats is avoided. The construction work of the FCZ is properly
designed such that no dredging work is required. To minimise the impacts to the vicinity of
the Project site, it is designed to have minimal construction work on
site. The scale of construction work
on-site is relatively small, and the number of vessels operating concurrently
are limited to a small number. The
installation time of fish farm structures is minimised and is expected to be
completed within a few weeks for each fish raft which would only cause
temporary disturbance to fisheries habitat and fishing ground. Main components of the rafts / cages are
manufactured off-site and will be towed to the Project site using tug
boat. On-site assembly and anchoring of
the fish rafts / cages will be assisted by a small number of marine vessels
such as sampans and small speed boats for up to a few trips per day. No heavy construction plant would be
used. To minimise the impact on
fisheries resources, the fish farm is designed to occupy minimal space which
will only occupy a thin surface layer (<0.5 m) within a small area.
These designs are expected to
control and reduce potential impacts to fisheries resources, and no
fisheries-specific mitigation measures are thus required during construction.
Taking into
consideration the impact assessments in the previous sections and with
effective implementation of the proposed mitigation measures, the significance
of residual impacts on fisheries resources including sensitive receivers such
as Tap Mun FCZ, Kau Lau Wan FCZ, Sham Wan FCZ and other ARs in the vicinity
have been evaluated. Residual impacts
occurring as a result of the proposed Project have been determined and are
discussed as follows:
§ 55
ha of fisheries habitat and fishing grounds will be affected during operation
of the FCZ. While the design of fish farm will only occupy a section of the water
column and a small area of seabed. With the small extent of affected area and
the overall low commercial value of fisheries resources, the impact due to the
loss of access to fishing grounds is considered to be of minor significance.
Furthermore, with the implementation of the proposed mitigation measures, the
potential impact on fisheries will be further minimised. No unacceptable
residual fisheries impacts during the construction and operation of the Project
are therefore anticipated.
§ In
addition, the establishment of the proposed FCZ would have positive effects on
fisheries resources. While the proposed FCZ would provide more fisheries
resources to the local and global fisheries market, the fish farm structures
would also provide artificial substrates, which could form habitat and shelter
for juveniles or adult fisheries resources. Besides, the reduced fishing
pressure may also have potential positive effect on fisheries resources within
and adjacent to the Project site.
As no
unacceptable impacts have been predicted to occur during the construction and
operation of this Project, monitoring of fisheries resources during these
project phases is not considered necessary.
A review of baseline information on
commercial fisheries resources, habitats and fishing operations surrounding the
waters of the proposed Project from available literature has been
conducted. Results of the review
indicated that although moderate to high levels of fishing operation with
moderate level of fisheries production were reported at the Project site,
similar levels of fisheries operation and production were also reported
elsewhere in the broad Assessment Area. Recent studies
suggested that the northeastern waters supported fisheries resources that are
mainly with low commercial value, with some commercially important families
recorded in the area. It remains as
important spawning ground and nursery area for fisheries resources. Areas which supported fish families with higher
commercial values, such as YCTMP and HHWMP are located at some distance away
from the Project site.
Within
the Assessment Area, fisheries sensitive receivers, including spawning
ground, nursery area, marine parks, ARs and existing FCZs have been identified. Based on the information
reviewed, the Project site does not represent a unique fishing ground, spawning
ground and nursery area for fisheries resources.
During the construction of the Project,
direct impacts arising from the proposed marine works include disturbance to
fisheries habitats and the loss of access to potential fishing grounds (~55
ha). Considering the temporary nature of
the disturbance and the majority of fisheries resources found in and around the
vicinity of the Project site are of low commercial value, unacceptable impacts
on fisheries are not expected. Moderate
to high fishing operations have been recorded at the Project site. Considering the temporary nature of construction
impact, overall, the impacts on fishing activity are considered to be of minor
significance and no unacceptable impacts are expected. Impact of elevated levels of underwater sound
as a result of construction activities are considered acceptable with the
presence of existing underwater sound from the nearby Tap Mun FCZ and other
FCZs in the vicinity, and marine
traffic at the vicinity of ferry routes. No fisheries-specific
mitigation measures are required during FCZ construction.
During FCZ operation, there will be
55 ha loss of access to fishing grounds.
The structures mainly occupy a section of the water column and a small
area of seabed confined to a thin surface layer
(<0.5 m). The presence
of fish farm structures will also provide hard substrates that could be
colonised by a variety of marine organisms and bringing potential positive
effect on fisheries resources.
Considering the relatively small area affected in the context of
surrounding similar habitat and the majority of fisheries resources found in
and around the vicinity of the Project site are of low commercial value,
unacceptable impacts on fisheries are not expected. The loss of access to fishing ground is also
considered to be small compared to the availability of fishing grounds elsewhere
in northeastern Hong Kong waters available for fishing activities. Suitable fishing grounds outside of these
structures can allow similar fishing activities to take place. Overall, the
impacts on fishing activity are of minor significance and no unacceptable
impacts are expected. Potential impacts
of elevated levels of underwater sound generated from the marine vessels in the
vicinity of the Project site are considered acceptable with the presence of
existing underwater sound from the nearby Tap Mun FCZ and other FCZs in the
vicinity, and marine traffic at
the vicinity of ferry routes.
Temporary relocation of fish rafts may occur over a short time,
therefore, unacceptable impacts are not anticipated. Impacts of changes in water quality arising from
FCZ operation are predicted to be largely confined in the vicinity of the
Project site within the maximum carrying capacity. No unacceptable change in water quality is
predicted at all fisheries sensitive receivers in both baseline and project
scenarios. The management of fish health
will be conducted regularly to prevent fish disease outbreaks, including the
Fish Health Inspection Programme to be conducted regularly by AFCD and the
implementation of good mariculture practices by fish farm owners. No fisheries-specific mitigation measures are
required during FCZ operation.
Overall, no
unacceptable impacts to fisheries are expected to occur. All of the potential construction and
operational fisheries impacts identified are deemed acceptable.
([2]) Legislative Council Panel on Food Safety and Environmental Hygiene (2019) Development of Mariculture.
([4]) Sumaila UR, Cheung WWL and Teh L (2007) Rebuilding Hong Kong’s Marine Fisheries: An Evaluation of
Management
Options. Fisheries Centre Research Reports 15 (3). pp.112.
([8]) Refers to the fisheries ancillary vessels which are used to gather catch from fishing vessels, and operate either in Hong Kong waters or further afield.
([9]) AFCD (2020) Proposed Injection into
the Fishing Moratorium Loan Scheme. Paper presented in Legislative Council
Panel on Food Safety and Environmental Hygiene.
([12]) Leung
AWY (1997) The epibenthic ichthyofauna of Tolo Harbour and Hong Kong's
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([13]) ERM
(2003). The Proposed Submarine Gas Pipeline From Cheng Tou Jiao Liquefied Natural
Gas Receiving Terminal, Shenzhen to Tai Po Gas Production Plant, Hong Kong. EIA
Study (EIA-089/2003). Prepared for The Hong Kong and China Gas Company Limited.
([15]) South China Sea Fisheries Research Institute (2017) Report on Survey of Fisheries Resources in Hong Kong (2010-2015). Prepared for AFCD.
([16]) South China Sea Fisheries Research Institute (2017) Main Commercial Families of
Fisheries Resources in Hong Kong.
Prepared for AFCD.
([17]) Country and Marine Parks Board Marine Parks Committee (2020) Fisheries Resources Surveys at Existing and Proposed Marine Parks, and Cape D’Aguilar Marine Reserve – Results and Conclusion.
([18]) ERM
(1998) Fisheries Resources and Fishing Operations in Hong Kong Waters, Final
Executive Summary, for Agriculture, Fisheries and Conservation Department.
([19])
State Key Laboratory of Marine Pollution, City University of Hong Kong
(2018) Provision of Survey Services of Ichthyoplankton, Zooplankton and
Juvenile Fish and Crustacean in the Potential Fisheries Protection Areas. Final
Executive Summary, for Agriculture, Fisheries and Conservation Department.
([21]) Leung PTY, Mak S, Ip J, Yau C, Lai V and Leung KMY (2014) Survey of Juvenile Fish Resources at the Three Marine Parks at Northeast Hong Kong. Prepared for Agriculture, Fisheries and Conservation Department, HKSAR Government.
([27]) References cited in BCL (1994) Marine
Ecology of the Ninepin Islands including Peddicord R and McFarland V (1996)
Effects of suspended dredged material on the commercial crab, Cancer magister. in PA Krenkel, J
Harrison and JC Burdick (Eds) Dredging and its Environmental Effects. Proc.
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([28]) Alabaster JS & Lloyd R (1984)
Water Quality Criteria for Freshwater Fisheries. Butterworths, London.