5.1
Ardeid Night
Roost Monitoring
With reference to the Pre-construction Ardeid Night
Roost survey (January 2021) findings that identified two active ardeid night
roosts within 100 m from the Project boundary (one approximately 40 m east of
the Project boundary and the other one approximately 45 m northeast of the
Project boundary), consequent monthly monitoring of these active ardeid night
roosts was done in accordance to the EM&A Manual Sections 7.3.10 and
7.3.11; and EIA Report Section 8.12.1.3.
The Ardeid Night Roost Monitoring survey was
conducted with the following objectives:
·
Check the status and
location of any active ardeid night roosts within 100 m from the Project
boundary (Survey Area) with reference to EM&A Manual Section 7.3.10;
·
Monitor the effectiveness
of proposed mitigation measures and detect any unpredicted indirect ecological
impacts arising from the proposed Project as specified in EIA Report Section
8.12.1.3; and
·
Recommend remedial actions,
where appropriate, based on the impact monitoring results (EIA Report
Section 8.12.1.3) for the implementation of the contractor as only
necessary.
5.1.2.1 Monitoring
Area
With reference from Section 7.3.10 of the approved
EM&A Manual, the monitoring was conducted in areas within 100 m from the
Project boundary. The monitoring area and vantage points for direct observation
of any active night roosts are shown in Appendix
O.
5.1.2.2 Monitoring Activity
5.1.2.2.1 Active Ardeid Night Roost
Current
Ardeid Night Roost Monitoring Survey focused on the two active night roosts
within the Survey Area (100 m from the Project boundary) that were previously
confirmed during the pre-construction Survey. These roosts include one that was
approximately 40 m east of the Project boundary and another around 45 m
northeast of the mentioned boundary (Section 3 of the approved
Pre-construction Survey Report of Ardeid Night Roost). Primary data
collection with the use of 8x and 10x binoculars; and field guides including
the Avifauna of Hong Kong (Carey et al., 2001) and The Birds of Hong Kong and
South China (Viney et al., 2005), was from about one
hour before sunset time until one hour after sunset with reference to Section
7.3.10 of the approved EM&A Manual. Sunset time was according to
Hong Kong Observatory (HKO). The survey was conducted on 19
June
2024.
Species
composition, abundance and locations of night roosts were recorded. Species
composition, abundance and location of pre-roosting aggregations (PRA) were
also noted. PRAs are gatherings of avian individuals prior to flying into a
night roost (Moore and Switzer, 1998). The time of return of the ardeids to the
pre-roost and the final night roost were also recorded. Direct observations
were made from vantage points adjacent the Project site with clear and
unobstructed view of any active roosting location (s) within the Survey Area.
However, aside from the established vantage points for the focused mangrove
strips along Shan Pui River, observations were also
conducted throughout the whole 100 m study site to cover other areas aside from
the mangrove strips.
Observations such as any changes in site
condition or disturbances detected or observed at the monitoring locations,
including both construction and non-construction related activities, during the
monitoring activity was recorded with reference to Section 7.3.10 of the
approved EM&A Manual. Additionally, other observations such as bird
droppings on the ground which may possibly indicate presence of night roosts
were noted in addition to noting of the roosting substrate (i.e.
substrate species and approximate height). Any breeding activity usage of the
roosting locations within the Survey Area was also noted.
5.1.2.2.2 Noise Monitoring
Monitoring Locations, Frequency, Time and
Parameters
The noise monitoring locations were established at 22°28’4.25”N, 114°1’41.32”E; and 22°28’10.43”N, 114°1’42.17”E for
NMS1 and NMS2 stations, respectively. Monitoring frequency was only once a
month in concurrence with the construction phase monthly monitoring of the
active night roosts for correlation. Monitoring time for both stations started
around 19:10, the earliest final night roost period recorded during the survey
and lasted for 30 minutes. Table 16
presents the monitoring parameters.
The Action and Limit Levels for Active Ardeid Night Roost Survey have
been set and are presented in Appendix C.
However, exceedances to the limit level were
endeavoured to be prevented by the full implementation of mitigation measures (Section
4.2 of the approved Pre-construction Survey Report of Ardeid Night Roost
and Sections 5.2.1-5.2.2 of this Report) during the construction
phase.
Event and Action Plan
In instances of exceedance/s in the action and/or
limit levels, the different measures as specified in Table 3.3 Event and
Action Plan for Construction Noise of the approved EM&A Manual and likewise presented in Appendix
H of this report shall be implemented as responses.
5.1.3.1 Active Ardeid Night Roost
The monitoring activity was conducted on 19
June
2024 and started around 18:09 (one hour before sunset) on a
low tide condition. During the pre-roost period (PRP), the period when avian
individuals gather first before flying into a night roost, individuals of
Chinese Pond Heron Ardeola bacchus
(2), Little Egret Egretta garzetta (7) and
Great Egret Ardea alba (3)
were observed in pre-roost aggregate (PRA) around 18:29
at the mudflat east side ANR1 of the Project boundary while individuals of
Chinese Pond Heron Ardeola bacchus (1), Little
Egret Egretta garzetta
(2)
and Great Egret Ardea alba (1)
were concurrently noted at the mudflat northeast side ANR2 of the Project
boundary (Table 17).
For
the final night roost at around 18:58, individuals of Chinese Pond
Heron Ardeola bacchus
(12), Little Egret Egretta garzetta (2) and Great Egret Ardea
alba (6) were observed at the roosting area ANR1 utilizing the understory
to canopy layer of the roosting substrate Sonneratia
apetala and S. caseolaris; while other
individuals of Chinese Pond Heron Ardeola bacchus (4), Little Egret Egretta
garzetta (2) and Great Egret Ardea
alba (1) were noted at ANR2 that utilized the understory to canopy layer of
the aforementioned roosting substrate.
No disturbance (construction related and/or otherwise) to
the active night roost areas was observed during the period. Bird droppings
were observed within the vicinity of the roosting area located east of the
Project boundary.
5.1.3.2 Noise
Monitoring
Noise monitoring activities were conducted on 19 June 2024
in concurrence with the construction phase monthly monitoring of the
pre-identified active night roosts. Noise monitoring started at 18:58 and
lasted for 30 minutes, until 19:28.
Current survey results showed noise levels (LAeq (30 min.)) at both monitoring stations to be well
below the action and limit levels as presented in Table 18.
No Action / Limit exceedance was recorded for noise
levels at stations (NMS1 and NMS2) in close proximity to the two active ardeid
night roosts (ANR1 and ANR2) observed within the Survey Area during the
reporting month.
5.1.4
Detection of Any
Unpredicted Indirect Ecological Impacts Arising from the Project
No unpredicted indirect ecological impacts that
arose from the project were noted during the current monitoring period.
5.1.5.1 Status and Location of Any Active
Ardeid Night Roost
Two
active ardeid night roost areas (ANR1 and ANR2) were observed within the Survey
Area during the June 2024 monitoring period. These roosts were located at the
mangrove strips in the east and northeast portions of the Project boundary.
These were used by individuals of Chinese Pond Heron Ardeola
bacchus, Great Egret Ardea
alba and Little Egret Egretta garzetta.
5.1.5.2 Noise Monitoring Results
Both noise levels at each of the monitoring
stations were below the action and limit levels.
5.2
Ecological
Monitoring of Birds
With reference to Section 7.3.6 of the EM&A
Manual, monthly ecological monitoring of birds, focusing on avifauna
species of conservation interest, and overwintering waterbirds utilising
wetland habitats in Fung Lok Wai and Nam Sang Wai as well as along Shan Pui River and Kam Tin River within the monitoring area (500
m from the Project Boundary) was conducted in addition to monitoring on the
utilization of wetland habitats by birds also within the same monitoring area
as required by Section 7.3.1 of the EM&A Manual.
5.2.2.1 Monitoring Area
The monitoring area included wetland habitats in
Fung Lok Wai and Nam Sang Wai as well as along Shan Pui
River and Kam Tin River within 500m from the Project boundary with reference to
Section 7.3.6 of the EM&A Manual. The location of point count
sites and transect routes is shown in Appendix
P.
5.2.2.2 Monitoring Activity
Avifauna
surveys on the different wetland habitats using the transect count and point
count methods were conducted last 13 June 2024 (daytime) and 19 June 2024
(night-time) which started at around 07:15 and 19:09. Additionally, the survey
overlooking the mudflats and mangroves in the Shan Pui
River was concurrently conducted on the same date with the daytime survey
during the low tide (generally 1.5m or below) period, and also started at
around 07:15. The methodology for the monitoring activity followed Sections
8.3.3.6 and 8.3.3.7 of the EIA Report (AEIAR-220/2019) and as
detailed below.
For
the transect count and point count methods, the presence and relative abundance
of avifauna species at various wetland habitats were recorded visually and
aurally.
Avifauna species were detected either by direct sighting or
by their call and identified to species level. Any notable behaviours such as
feeding, roosting and breeding were also recorded. Bird species encountered
outside the point count locations and walk transects were also recorded. A
comprehensive list of species recorded from the Assessment Area was prepared,
with wetland-dependence, conservation and/or protection status indicated.
Ornithological nomenclature in this report follows Carey et al. (2001), Viney et al. (2005) and the most recent updated list from
Hong Kong Bird Watching Society (HKBWS).
Noise levels were recorded with the methodology and
equipment as mentioned in Section 3.4 and Section 3.2, respectively, of this EM&A report.
The parameter as shown in was recorded at each of the point count locations.
In addition to recording of noise levels, any changes in site condition
or disturbances detected or observed at the monitoring locations, including
both construction and non-construction related activities with reference to Section
7.3.7 of the EM&A Manual were also noted.
5.2.2.3 Data Analysis
For
the bird communities, the monitoring results were compared to pre-construction
baseline condition during the dry and wet seasons as summarized in the Baseline
Bird Survey Report with reference to Section 7.3.8 of the EM&A
Manual. However, to further account the seasonality, monitoring results of
the current month were compared to the results of the corresponding month of
the baseline data.
The
data for point count method and transect walk method were presented separately
to account for the difference in the survey effort of the two methods. For each
method, abundance and species composition of the avifauna communities during
the monitoring month were summarized.
To
check the presence of variation in bird abundance between baseline and impact
monitoring, t-test was applied (α = 0.05). Moreover, to check the presence
of variation in bird species diversity, the two-sided Hutcheson t-test was also
used. The two-sided Hutcheson t-test was developed as a method to compare the
diversity of two community samples using the Shannon diversity index (Hutcheson
1970). Shannon diversity index will be computed using the formula, 
where,
H’ = Shannon Diversity Index; Pi = proportion of the population of
species; i = number of species in sample; ln
= natural logarithm. Shannon diversity index is used as it accounts the
proportion (relative abundance) of each species; thus, it gives a better
description of diversity than a plain number of species (species richness).
The Action and Limit Levels for ecological monitoring of birds have been
set and are presented in Appendix C.
Wetland habitat utilization during the construction phase monitoring
shall only be compared seasonally, hence the comparison shall only be done
after all the data (dry season and wet season) were collected with reference to
Appendix 8.5 of the approved EIA Report.
Results
of the avifauna survey on the different habitats within the monitoring area
using the transect count and point count methods as conducted last 13 June 2024
(daytime) and 19 June 2024 (night-time) which started at around 07:55 and
19:40, are presented in Sections 5.2.3.1 and 5.2.3.2.
Meanwhile, results for the surveys overlooking the mudflats and mangroves in
the Shan Pui River, with monitoring activities
conducted on similar date with the daytime survey during the low tide
(generally 1.5m or below) period around 07:55 had results presented in Section
5.2.3.3.
5.2.3.1 Abundance
5.2.3.1.1 All Avifauna Species
An overall
total of 437 avifauna individuals were recorded in the monitoring area during
the June 2024 monitoring period, of which 284 individuals were recorded from
the point count method and 153 individuals from the transect walk method.
Relative to the June 2017 baseline data (point count method = 121; and transect
walk = 69), increases were noted for both the point count and transect walk
methods.
Details of these findings are summarized in Table 20.
No Action / Limit exceedance was recorded for the abundance of all
avifauna species (including but not limited to overwintering waterbirds) for
both the point-count and transect walk method.
5.2.3.1.2 Avifauna Species of Conservation
Importance
Of the
437 avifauna individuals recorded in the monitoring area during the June 2024
monitoring period, 138 individuals (point count method = 93
individuals; transect walk method =
45
individuals) were of conservation importance. With reference to June
2017 data, (point count method = 45; and transect walk = 40), an increase was
noted for both point count and transect walk method. Details of these findings are summarized in Table 21.
No Action / Limit exceedance was recorded for the abundance of avifauna
species with conservation importance only for both the point-count and transect
walk method.
5.2.3.2 Diversity (Species Richness1
and Shannon Diversity Index2)
5.2.3.2.1 All Avifauna Species
A total
of 33 avifauna species (species richness) were recorded during the June 2024
monitoring period, of which, 32 species were recorded by the point count method
while 30 species were noted by the transect walk method. Relative to the
baseline data (point count method = 25 species; transect walk method = 13
species), increases in total species richness for both transect walk count and
point count methods were recorded. In terms of Shannon diversity index (H’)
values, current result in point count method showed an increase (t-value =
0.30; t-crit = 1.97; p-value = 0.76; α = 0.05) relative to the baseline
reference value. The current results in the transect walk method also showed a
significant increase (t-value = 6.39; t-crit = 1.98; p-value = 2.22E-09; α
= 0.05) from baseline reference value. Details of these findings are
summarized in Table 22, Appendix F.6.1, and Appendix F.6.2.
No Action / Limit exceedance was recorded for the decline in species
diversity of all avifauna species in the point count / transect walk method.
5.2.3.2.2 Avifauna Species of Conservation
Importance
Of the
33 avifauna species identified during the June 2024 monitoring period, 9
species were of conservation importance (point count method = 9 species;
transect walk method = 7 species). Meanwhile, relative to the baseline values
in June 2017 (point count method = 5 species; transect walk method = 3
species), an increase in the number of species with conservation importance was
recorded with both the point count and transect walk method. In terms of
Shannon diversity index (H’), an increase was noted in point count method
(t-value = 0.12; t-crit = 1.98; p-value = 0.90; α = 0.05) while a
significant increase in transect walk method (t-value = 3.50; t-crit = 2.00;
p-value = 8.22E-04; α = 0.05) was observed relative to the baseline
reference values. Details of these findings are summarized in Table 23, and Appendix F.6.3.
No Action / Limit exceedance was recorded for the decline in species
diversity of avifauna species with conservation importance in the point count /
transect walk method.
5.2.3.3 Wetland Habitat Utilization
Avifauna communities were observed during the current monitoring period
in the different wetland habitats, i.e. mangrove,
modified watercourse, ponds, and reed bed.
With reference to Section 7.3.1 of the EM&A Manual,
the utilization of the wetland habitats by birds within the monitoring area was
recorded and monitored.
5.2.3.3.1 All Avifauna Species
During
the current monitoring period, majority of the different wetland habitats were
observed with Very Low (VL) abundance. In terms of species richness, different
wetland habitats were generally observed with Low (L) and Moderate (M) number
of species (Table 24).
5.2.3.3.2 Avifauna Species of Conservation
Importance
Majority
of the different wetland habitats had Very Low (VL) abundance of avifauna
species of conservation importance; and were generally utilized by Very Low
(VL) number of species (Table 25).
5.2.3.4 Noise Levels
Noise
levels LAeq (30 min) recorded on 13 June
2024(daytime) and 19 June 2024(night time) from each of the point count
locations during the ecological bird monitoring are shown in Table 26.
No Action / Limit exceedance was recorded for noise levels at all
stations for the ecological monitoring of birds in the reporting month.