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 9th and 18th October 2013. The dolphin monitoring schedule
for the reporting period is shown in Appendix
D.
6.8
From these surveys, a total of 64.94 km of survey effort was collected,
with 98.0%
of the total survey effort being conducted under favourable
weather conditions (i.e. Beaufort Sea State 3 or below with good visibility)
Out of the 64.94 km of survey effort, the
total survey effort conducted on primary lines (the vertical lines
perpendicular to the coastlines) was 43.05
km.
6.9
7 groups of 21 Chinese White
Dolphins were sighted from primary lines. These dolphin
groups were mainly concentrated near Tai O Peninsula and Fan Lau, while no
sighting was made in the middle portion of the survey area (i.e. between Tai O
and Fan Lau). None of the sightings
were made near the HKLR09 alignment.
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 October’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: Oct
9th |
14.1 |
28.2 |
Set
2: Oct
18th |
19.0 |
71.1 |
6.11
A total of 16
re-sightings of known individual Chinese White Dolphins were made during the October’s
surveys.
6.12
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.
6.13
Evaluation of impacts on
dolphins due to construction work will be conducted in the quarterly EM&A
report.
6.14
Detailed monitoring methodology
and results can be found in Appendix I.