6.1
According to Section 10 of the
EM&A Manual, four kinds of ecological monitoring works are required during
the construction phase, namely dolphin monitoring, construction-phase
underwater noise monitoring, dolphin behavior monitoring and land-based dolphin
behavior and movement monitoring. The 30 days of construction-phase underwater noise monitoring, dolphin behavior
monitoring and land-based dolphin behavior and movement monitoring were completed in July 2013.
6.2
The monitoring work shall be
undertaken by suitably qualified specialist(s), (i.e. dolphin specialist and
bio-acoustician), who shall have sufficient (at least 5-10 years) relevant
post-graduate experience and publication in the respective aspects. They should
be approved by Agriculture, Fisheries and Conservation Department (AFCD) and
Environmental Protection Department (EPD).
6.3
According to EM&A Manual
Section 10.3.2, a dolphin monitoring programme should
be set up to verify the predictions of impacts and to ensure that there are no
unforeseen impacts on the dolphin population during construction phase.
6.4
Following the requirement in
the EM&A Manual Section 10.4.1, the dolphin
monitoring should adopt line-transect vessel survey method, and cover the
following line-transect survey areas as in AFCD annual marine mammal monitoring
programme.
6.5
For this contract, dolphin
monitoring will be carried out in the West Lantau (WL) along the line transect
as depicted in Figure 1 of Appendix I. The co-ordinates of all transect lines are shown in Table 6.1.
Table 6.1 Co-ordinates
of transect lines in WL survey area
|
Line No. |
Easting |
Northing |
Line No. |
Easting |
Northing |
||
|
1 |
Start Point |
803750 |
818500 |
7 |
Start Point |
800200 |
810450 |
|
1 |
End Point |
803750 |
815500 |
7 |
End Point |
801400 |
810450 |
|
2 |
Start Point |
803750 |
815500 |
8 |
Start Point |
801300 |
809450 |
|
2 |
End Point |
802940 |
815500 |
8 |
End Point |
799750 |
809450 |
|
3 |
Start Point |
802550 |
814500 |
9 |
Start Point |
799400 |
808450 |
|
3 |
End Point |
803700 |
814500 |
9 |
End Point |
801430 |
808450 |
|
4 |
Start Point |
803120 |
813600 |
10 |
Start Point |
801500 |
807450 |
|
4 |
End Point |
801640 |
813600 |
10 |
End Point |
799600 |
807450 |
|
5 |
Start Point |
801100 |
812450 |
11 |
Start Point |
800300 |
806500 |
|
5 |
End Point |
802900 |
812450 |
11 |
End Point |
801750 |
806500 |
|
6 |
Start Point |
802400 |
811500 |
12 |
Start Point |
801760 |
805450 |
|
6 |
End Point |
800660 |
811500 |
12 |
End Point |
800700 |
805450 |
6.6
Dolphin transect survey was
carried out at least twice a month (i.e. complete all the transect lines of
West Lantau survey area twice per month) throughout the construction period.
6.7
Dolphin monitoring was carried
out on 4th and 11th
November 2016. The dolphin monitoring schedule for the
reporting period is shown in Appendix D.
6.8
From these surveys, a total of 68.20 km of survey effort was
collected, with 96.1% of the total survey effort being
conducted under favorable weather conditions (i.e. Beaufort Sea State 3 or
below with good visibility) Out of the 68.20 km of survey effort, the
total survey effort conducted on primary lines (the horizontal lines
perpendicular to the coastlines) was 44.54 km.
6.9
7 groups of 28 Chinese White Dolphins were sighted from primary lines.
None of the dolphin groups was associated with an operating fishing vessel. Distribution
of the 8 dolphin sightings made during November’s surveys is shown in Figure 4 of Appendix I. The sighting
were evenly distributed across the survey area, ranging from just to the south
of HKLR alignment in the north, to Fan Lau in the south, with no particular
concentration (Figure 4 of Appendix I). It appeared that
dolphin groups occurred more often in offshore waters than inshore waters
within the survey area in this monitoring month (Figure 4 of Appendix I).
6.10
Dolphin encounter rates deduced
from the survey effort and on-effort sighting data made under favourable conditions (Beaufort 3 or below) are shown in Table 6.2.
Table 6.2 Dolphin
encounter rates (sightings per 100 km of survey effort) in November’s surveys
|
|
Encounter rate
(STG) (no. of on-effort dolphin sightings per 100 km of
survey effort) |
Encounter rate
(ANI)
(no. of dolphins from all
on-effort sightings per 100 km of survey effort) |
|
|
Primary Lines Only |
Primary Lines Only |
||
|
WL |
Set
1: November 4th |
4.5 |
4.5 |
|
Set
2: November 11th |
28.6 |
128.8 |
|
6.11
The average group size of Chinese White Dolphins was 3.9 individuals
per group during November’s surveys, which
was similar to the averages in previous months of monitoring surveys.
6.12
Half of the eight dolphin
groups were small in size with 1-3 animals, while the other half were moderate
in size with 4-8 animals per group (Appendix II).
6.13
During this month of dolphin
monitoring, marine construction activities have continued under this
contract. However, no adverse
impact on Chinese white dolphins was noticeable from general observations.
6.14
Evaluation of impacts on
dolphins due to construction work will be conducted in the quarterly EM&A
report.
6.15
Detailed monitoring methodology
and results can be found in Appendix I.
6.16
A total of 64 days of
additional monitoring according to the Proposal for Land-based Dolphin Behaviour and Movement Monitoring had been completed in
August 2016.
6.17
Detailed monitoring methodology and results will be provided in a
separate report.