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 8th and 20th June 2016. The dolphin monitoring schedule for the
reporting period is shown in Appendix D.
6.8
From these surveys, a total of 66.45 km of survey effort was collected,
with 100% 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 66.45 km of survey effort, the total survey
effort conducted on primary lines (the horizontal lines perpendicular to the
coastlines) was 44.79 km.
6.9
8 groups
of 17 Chinese White Dolphins were sighted from primary lines. Distribution
of the 11 dolphin sightings
made during June’s surveys is shown in Figure 4 of Appendix I. All except two sightings were located in the southern portion of the
survey area, with relatively even distribution from the offshore area of Kai
Kung Shan to Fan Lau. The other two sightings were made to the north of Tai O
Peninsula. Notably, no dolphin was
sighted at all near the HKLR09 alignment (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 June’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: June 8th |
8.9 |
22.3 |
|
Set 2: June 20th |
26.9 |
53.7 |
|
6.11
The average group size of Chinese White
Dolphins was 2.2 individuals
per group during June’s surveys, which was much lower than the averages in
previous months of monitoring surveys.
6.12
Almost
all dolphin groups were small in size, with five groups with single animals and
four other groups with 2-3 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
Additional land-based dolphin behavior and movement
monitoring was conducted on 2nd and 16th June 2016 in the
reporting month. The progress of the monitoring is summarized in the Table 6.3.
Table
6.3 Progress
Record of Additional Land-based Dolphin Behaviour and
Movement Monitoring in June 2016
|
Date |
Time |
Weather |
Number of Staff |
Number of Dolphin Sighting |
|
|
Beaufort |
Visibility |
||||
|
02/06/16 |
09:10 - 14:32 |
3-4 |
2.5 |
3 |
0 |
|
16/06/16 |
09:27 - 14:31 |
2-3 |
2.5 |
3 |
1 |
6.17 Detailed
monitoring methodology and results will be provided in a separate report after
the completion of full set of additional land-based dolphin behavior and
movement monitoring.