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 3rd and 10th December 2015. The dolphin monitoring schedule
for the reporting period is shown in Appendix
D.
6.8
From these surveys, a total of 66.61 km of survey effort was
collected, with 82.8% 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 66.61 km of survey effort, the
total survey effort conducted on primary lines (the horizontal lines
perpendicular to the coastlines) was 45.11 km.
6.9
6 groups of 19
Chinese White Dolphins were sighted from primary lines. Distribution of the 7 dolphin sightings made during December’s
surveys is
shown in Figure 4 of Appendix I. These sightings
were scattered from Tai O Peninsula to Fan Lau with no particular
concentration, and it appeared that more sightings were made at the offshore
waters than inshore waters. None of
the dolphin sightings were made near the HKLR09 alignment during 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 December’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: December 3rd |
12.4 |
62.2 |
Set
2: December 10th |
14.1 |
33.0 |
6.11
The average group size of Chinese White Dolphins was 3.0 individuals
per group during December’s surveys, which
was slightly lower than the ones in previous months of monitoring surveys.
6.12
Five of the seven dolphin
groups were composed of only 1-2 animals, while the other two dolphin groups
were moderate in size with five and eight animals respectively.
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 1st and 8th December 2015 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 December 2015
Date |
Time |
Weather |
Number of Staff |
Number of Dolphin Sighting |
|
Beaufort |
Visibility |
||||
01/12/15 |
08:59
- 14:30 |
2 |
3 |
3 |
2 |
08/12/15 |
08:53
- 14:24 |
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.