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 1st and 13th March 2017. The dolphin
monitoring schedule for the reporting period is shown in Appendix D.
6.8
From these surveys, a total of 66.66 km of survey effort was collected, with 90.7% 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 66.66 km of survey
effort, the total survey effort conducted on primary lines (the horizontal
lines perpendicular to the coastlines) was 42.97 km.
6.9
4 groups of 13 Chinese White Dolphins were sighted from
primary lines. Notably, none of the dolphin groups were associated with any operating
fishing vessel. Distribution of the dolphin sightings made during March’s
surveys is shown in Figure 4 of Appendix D. These sightings were located to the
west of Kai Kung Shan, near Tai O Peninsula, and to the north of Sham Wat just
outside of the WL survey area which was made just before on-effort search (Figure
4 of Appendix D). Only one dolphin group was sighted in the vicinity of the
HKLR09 alignment (Figure 4 of Appendix D).
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 September’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: March 1st |
5.6 |
11.2 |
Set 2: March 13th |
4.7 |
4.7 |
6.11
The average
group size of Chinese White Dolphins was 3.3 individuals per group during March’s
surveys, which was slightly higher than the averages in previous months of
monitoring surveys.
6.12
2 of the 4
dolphin groups were small in size with only 1-2 animals per group, while the
other two groups were medium-sized with 4-6 animals per group.
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.