9.1.1
The Assessment of potential impacts on
fisheries arising from construction and operation of the proposed Project are
presented in this section of the EIA Report.
This fisheries assessment is based on a desktop review of the latest
relevant literature. It includes a description of baseline conditions,
evaluation of potential impacts, and recommended mitigation measures, where
necessary. The objectives of the fisheries impact assessment are to:
·
Establish the importance of the fisheries habitats that may be affected
by construction and operation of the Project.
·
Identify fisheries sensitive receivers.
·
Assess the scale of possible impacts on fisheries resources arising from
the proposed works.
·
Identify any necessary mitigation measures and evaluate residual
impacts.
·
Assess the need for a fisheries monitoring and audit programme.
9.2.1
Evaluation of fisheries impacts in
Hong Kong was conducted according to criteria set out in the EIAO TM.
These criteria provide for the complete and objective identification,
prediction and evaluation of potential fisheries impacts. In this regard, Annex
9 of the Technical Memorandum sets out criteria for evaluating fisheries
impact while Annex 17 denotes the guidelines for fisheries impact
assessment.
9.2.2
Other legislation that applies to
fisheries and is relevant to fisheries assessment includes the:
·
Fisheries Protection
Ordinance (Cap. 171) – It
promotes the conservation of fish and other forms of aquatic life within the
waters of Hong Kong and regulates fishing practices to prevent activities
detrimental to the fishing industry.
·
Marine Fish Culture
Ordinance (Cap. 353) – It
designates, regulates and protects fish culture zones (FCZs) from injury to
fish and pollution of waters.
·
Water Pollution Ordinance (Cap. 358) – It sets limits to water quality
parameters in various Water Control Zones.
9.3.1
Baseline information on fisheries in
the Assessment Area was elucidated via a desktop review of the literature. This review included relevant fisheries
baseline data presented in AFCD’s Port Survey 2001/2002 and incorporated the
most recent information available in other reports and publications. Potential
impacts on the Fish Culture Zone at Tung Lung Chau are also discussed. The
impact assessment followed the criteria and guidelines for evaluating and
assessing fisheries impacts as stated in Annexes 9 and 17 of the EIAO
TM.
9.4.1
In Hong Kong, marine-based commercial
fishing operations are classified as capture or culture fisheries. According to
AFCD (2005), in 2004, Hong Kong’s capture fisheries’ fishing fleet comprised
about 4,630 vessels, about half of which were sampans or non-mechanised boats.
The Hong Kong fleet was manned by 9,500 local fishers, mainly family members,
and also employs Mainland deckhands. In
terms of production, in 2004, the capture fisheries industry yielded about
167,500 tonnes of fisheries produce valued at about HK$1,600 million. About 90%
of the catch was caught in waters outside Hong Kong (AFCD 2004) on the
traditional fishing grounds over the continental shelf of the East and South
China Seas.
9.4.2
Some recent data on the local capture
fisheries industry against the background of heavy exploitation and
over-fishing of inshore fisheries resources are shown in Table 9.1. Since 1999, Mainland
Authorities have implemented a fishing moratorium for two months during
midsummer for South China Sea fishing grounds. This fishing ban (from 1 June to
1 August) prohibits fishing activity by the Hong Kong fleet in the South China
Sea outside HKSAR waters except by gill-netting, long-lining, hand-lining and
cage trapping.
Table 9.1 Recent Hong Kong Capture Fisheries Industry Figures
|
Parameter
|
2004
|
2003
|
2002
|
2001
|
2000
|
1999
|
|
Fishing fleet size (No. of vessels)
|
4,630
|
4,600
|
4,470
|
5,100
|
5,250
|
5,170
|
|
Portion of fishing fleet comprising sampans (P4) and
non-mechanised vessels
|
No data
|
No data
|
53%
|
54%
|
51%
|
44%
|
|
Local fishers engaged in capture fisheries
|
9,500
|
10,100
|
10,860
|
11,560
|
11,900
|
12,900
|
|
Mainland deckhand employed
|
No data
|
No data
|
4,100
|
4,560
|
5,200
|
6,300
|
|
Production (tonnes)
|
167,500
|
157,400
|
169,790
|
174,000
|
157,010
|
127,780
|
|
Value of produce (HK$ million)
|
1,600
|
1,500
|
1,600
|
1,700
|
1,600
|
1,500
|
Note: no data – data were
unavailable at time of reporting
Source: AFCD
9.4.3
Culture fisheries activities, on the
other hand, include 26 fish culture zones (FCZs) located in various sheltered
embayments across the HKSAR and occupy about 209 ha of sea area. Typically,
fish farms are relatively small scale, family-run operations consisting of one
or two rafts with an average size of about 260m2. In 2004, there
were 1,125 licensed operators at these FCZs. With effect from June 2002, the Marine
Fish Culture Ordinance was amended to allow licenses to be transferred. The
annual production in 2004 by the marine fish culture industry was about 1,540
tonnes of fish valued at HK$79 million and catering for about 9.1% of local
demand for live marine fish (AFCD 2005). Some recent figures on the local
marine culture fisheries are presented in Table 9.2.
Table 9.2 Recent
Hong Kong Fish Culture Industry Figures
|
Parameter
|
2004
|
2003
|
2002
|
2001
|
2000
|
1999
|
|
Licensed mariculturists
|
1,125
|
1,155
|
1,237
|
1,320
|
1,418
|
1,454
|
|
Production (tonnes)
|
1,540
|
1,490
|
1,210
|
2,470
|
1,770
|
1,250
|
|
Value (HK$ million)
|
79
|
76
|
57
|
136
|
102
|
66
|
Source: AFCD
Capture Fisheries
9.4.4
With regard to the capture fisheries operations
and resources, the Assessment Area comprises fishing grounds within Junk Bay.
9.4.5
According to the most recently
published data (AFCD 2003), annual catches of adult fish within Junk Bay are typically
in the range 100-200kg /ha, but reach higher levels of 200-400kg / ha at the
middle southern edge and southeast areas of the bay. In comparison with other
fishing grounds across Hong Kong, the fishing grounds of Junk Bay are therefore
considered to support low to moderate adult fish production.
9.4.6
Fry production in Junk Bay, used as
grow-out stock by mariculturists, is very limited (AFCD
2003). Latest figures indicate
that the fry caught in the inner Junk Bay waters were at a low density of >0
– 50 tails/ha (AFCD 2003). No fry production was recorded from outer Junk Bay.
In the same way, Junk Bay was not considered to be an important spawning or
nursery ground for commercially important species (ERM 1998).
9.4.7
The scale of fishing operations in
terms of number of fishing vessels operating in Junk Bay is considered to be
low to moderate (100 – 400 vessels) as compared with other fishing grounds of
Hong Kong. Junk Bay supports a range of fishing vessel operations dominated by
P4 sampans but also including gill-netters, handliners and miscellaneous craft.
In addition, small numbers of stern trawlers, long liner, and purse seine
vessels operate in Junk Bay. According to AFCD data, limited numbers of shrimp
trawlers generally confine fishing effort to outer Junk Bay. In terms of vessel
size, all fishing vessels operating in Junk Bay were less than 15m in length
with the exception of a small number of larger vessels operating at the outer
areas of Junk Bay.
9.4.8
At inner Junk Bay, production levels
are generally low compared to other local fishing grounds with the exception of
moderate catches (20-40kg/ha) of seabream (Sparidae) and rabbitfish
(Siganidae). Among the other most
common components of the catch by Hong Kong fisheries, inner Junk Bay has
low-moderate production of crab (10-20kg/ha) and low production (5-10kg/ha) of
croaker (Sciaenidae). The waters of inner Junk bay also typically yield very
low production (<5 kg/ha) of sardine (Clupeidae), scad (Carangidae), anchovy
(Engraulidae), threadfin seabream (Nemiperidae), squid and shrimp.
9.4.9
Outer Junk Bay fishing grounds on the
other hand, generally support high production (40-60kg/ha) of seabream
(Sparidae) and rabbitfish (Siganidae) and moderate production (20-40kg/ha) of
crabs. These waters also yield low-moderate
production (10-20kg/ha) of scad (Carangidae), croaker (Sciaenidae) and squid,
and low production (5-10kg/ha) of anchovy (Engraulidae), sardine (Clupeidae)
and shrimp. Threadfin seabream
(Nemiperidae) have very low (<5kg/ha) production levels.
9.4.10
Of the fishes with moderate to high
yields caught in the Assessment Area, rabbit fish are fast-growing fishes of
relatively low commercial value. Seabream are typically of medium commercial
value.
9.4.11
Based on annual adult fish and fry
production figures, the dollar value of catches was regarded as moderate
(HK$2,000 – 5,000/ha/yr) at inner Junk Bay. Waters at outer Junk Bay are
generally considered to be of greater importance to the fishing industry having
moderate – high value (HK$5,000 – 10,000/ha/yr) in comparison with other
fishing grounds in Hong Kong.
Culture Fisheries
9.4.12
Marine culture fisheries are present
in the region of the project works in waters outside Junk Bay off the northwest
coast of Tung Lung Chau. The Tung Lung
Chau FCZ is a fisheries sensitive receiver and would be located about 6 km from
the project works.
9.4.13
As at 20th Febraury 2005,
the Tung Lung Chau FCZ consisted of 58 licensed rafts with a total licensed
area of 12,234 m2. A total of 58 licenses have been issued to
operators at this FCZ.
9.4.14
Although no figures are available on
the individual production of these FCZs, it is known that Hong Kong production
in 2004 totalled 1,540 tonnes. The fish species commonly cultured in FCZs are
of high commercial value including the
orange-spotted grouper (Epinephelus coioides), giant grouper (Epinephelus lanceolatus), mangrove snapper (Lutjanus
argentimaculatus) and the pompano (Trachinotus blochii).
9.4.15
Based on
the information presented above, the fisheries within the Assessment Area are
considered to range from low to moderate value and importance to the Hong Kong
fishery.
9.4.16
Low to
moderate catches in inner Junk Bay and moderate to high catches in outer Junk
Bay waters as compared with other Hong Kong fishing grounds are dominated by
fish species of low commercial value often sold as fish feed in mariculture.
These waters attract a relatively low to moderate level of capture fishing
operations. There is one fish culture
zone located in adjacent waters at Tung Kung Chau.
Construction Phase
9.5.1
Potential
impacts on fisheries resources arising from Project would be direct loss of
fishing ground at inner Junk Bay. Impacts may also arise indirectly through
deterioration in water quality, particularly due to release of sediments into
the water column during dredging.
Loss of fishing grounds
9.5.2
The
reclamation for the WCR is considered to be of a relatively moderate scale and
would result in the permanent loss of approximately 16.3 ha of fishing ground
due to WCR reclamation and a further 0.2ha of fishing ground due to
construction of piers for CBL.
9.5.3
Due to
the generally low importance of the fishing area in inner Junk Bay to the Hong
Kong fishery and the low production at this area, the direct impact of the
project on fisheries resources and operations was regarded as low.
Effects of suspended sediments
9.5.4
Temporary
elevation in suspended sediment (SS) during dredging works of Phase 1 WCR
reclamation is identified as a potential impact on water quality for primary
consideration because at high levels sediment may cause injury to fisheries
resources. For instance, high SS levels
may clog gill structures and hinder transfer of oxygen. Eggs and early life
stages (fry) are more susceptible to smothering of respiratory surfaces due to
high sediment levels. Susceptibility generally decreases with age, so that
adult fishes are the least sensitive to effects from sediments. Suspended
sediment fluxes occur naturally in the marine environment, particularly in
estuaries, and consequently fish have evolved behavioural adaptations to
tolerate increased SS loads, including clearing their gills by flushing more
water over them. Where SS levels become excessive, fish may move to less turbid
waters.
9.5.5
Based on
water quality model predictions taking into account the recommended deployment
of silt curtains, the suspension of sediment into the water column by dredging
is not expected to have a significant impact on fisheries resources.
9.5.6
Tung
Lung Chau FCZ is located approximately 6km away from the proposed project. It is predicted that elevations in SS at this,
the only fisheries sensitive receiver, would be negligible and would not result
in adverse impacts on cultured fish.
Decrease in dissolved oxygen concentrations
9.5.7
The
relationship between SS and DO are complex, with increased SS in the water
column combining with a number of other effects to reduce DO concentrations in
the water column. Elevated SS reduces
light penetration, lowers the rate of photosynthesis by phytoplankton and thus
lowers the rate of oxygen production in the water column. Elevated sediment can also cause increased
energy retention from sunlight, resulting in higher temperatures, and hence the
potential for lower oxygen levels (because oxygen is more soluble in colder
water). Low oxygen has a particularly
adverse effect on the eggs and larvae of fish, as at these stages of
development, high levels of oxygen in the water are required for growth due to
high metabolic rates.
9.5.8
Based on
the water quality modelling results presented in Section 5, there are not
expected to be significant reductions in DO levels which could impact fisheries
resources.
Operation
Phase
9.5.9
No
impacts on fisheries resources are expected during the operation phase of the
project.
Cumulative
Assessment
9.5.10
No concurrent project in the
Assessment Area was identified that would give rise to cumulative impacts on
fisheries. Hence, no impacts to fisheries beyond those identified and evaluated
in the assessment for this Project are expected.
9.6.1
According
to the EIAO TM, the order of priority for mitigating impacts should be
avoidance, minimisation and compensation.
9.6.2
Dredging,
reclamation and marine construction activities incorporate constraints that serve
as appropriate mitigation to control environmental impacts to with acceptable
levels. Since no unacceptable adverse
impacts on fisheries are predicted, there would be no need for
fisheries-specific mitigation measures.
The mitigation measures recommended in Section 5 of this EIA Report for controlling water quality would serve also
to protect fisheries from indirect impacts and ensure no unacceptable impact on
fisheries resources and operations.
9.7.1
Based on
the above assessment, the residual impact of the project would be limited to
loss of approximately 16.5ha of fishing ground in Junk Bay. This loss is not
expected to impact production by the Hong Kong fishery as a whole.
9.8.1
Actual
impacts from dredging operations during the construction phase would be
monitored through an EM&A programme (see the separate EM&A
Manual). Monitoring and audit
activities for detecting and mitigating any unacceptable impact on water
quality would also serve to protect fisheries resources. Specific EM&A activities to assess the
effects of the project on commercial fisheries resources are not deemed
necessary.
References
Agriculture, Fisheries and Conservation Department
(2003). Port Survey 2001/2002
Agriculture, Fisheries and Conservation Department
(2004). Fisheries. http://www.afcd.gov.hk
ERM (1998). Fisheries Resources and
Fishing Operations in Hong Kong Waters. Report commissioned by AFD.