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 18 December
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 16:44, 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 18 December 2024 and
started around 16:43 (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 (4),
Great Egret Ardea alba (1)
and Grey Heron Ardea
cinerea (1) were observed in pre-roost aggregate (PRA)
around 17:28 at the mudflat east side ANR1 of the Project
boundary while individuals of Chinese Pond Heron Ardeola
bacchus (18), Great Egret Ardea
alba (1) and Little Egret Egretta garzetta (2) were
concurrently noted at the mudflat northeast side ANR2 of the Project boundary (Table 17).
For
the final night roost at around 17:45, individuals of Chinese Pond
Heron Ardeola bacchus
(8),
Great Egret Ardea alba
(2) and Grey Heron Ardea
cinerea (1) 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
(27), Great Egret Ardea
alba (6) and Little Egret Egretta
garzetta (3) 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 18
December 2024 in concurrence with the construction phase monthly monitoring of
the pre-identified active night roosts. Noise monitoring started at 17:45 and
lasted for 30 minutes, until 18:15.
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 December 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, Little Egret Egretta garzetta and Grey Heron Ardea
cinerea.
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 4 December 2024 (daytime) and 18 December
2024 (night-time) which started at around 07:15 and 18:00, respectively. 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, respectively. 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 4 December
2024 (daytime) which started at around 07:15 and 18 December 2024 (night-time)
which started at around 18:00 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 07:15
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 1132 avifauna individuals were recorded in the monitoring area
during the December 2024 monitoring period, of which 914 individuals were
recorded from the point count method and 218 individuals from the transect walk
method. Relative to the December 2016 baseline data (point count method = 530;
and transect walk = 85), a significant increase was noted for both point count
method and transect walk method.
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
1132 avifauna individuals recorded in the monitoring area during the December
2024 monitoring period, 704 individuals (point count method = 568 individuals;
transect walk method = 136 individuals) were of conservation importance. With
reference to December 2016 data, (point count method = 462; and transect walk =
16), an increase was noted for both the point count and transect walk methods. Details
of these findings are summarized inTable 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 62 avifauna species (species richness) were recorded during the
December 2024 monitoring period, of which, 62 species were recorded by the
point count method while 36 species were noted by the transect walk method.
Relative to the baseline data (point count method = 35 species; transect walk
method = 22 species), an increase in total species richness for both point
count and transect walk method was recorded. In terms of Shannon diversity
index (H’) values, current result in point count method showed an increase
(t-value = 10.42; t-crit = 1.96; p-value = 3.20E-24; α = 0.05) relative to
the baseline reference value. The current results in the transect walk method
showed an increase (t-value = 2.58; t-crit = 1.97; p-value = 1.08E-02; 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
62 avifauna species identified during the December 2024 monitoring period, 29
species were of conservation importance (point count method = 29 species;
transect walk method = 15 species). Meanwhile, relative to the baseline values
in December 2016 (point count method = 18 species; transect walk method = 5
species), an increase in the number of species with conservation importance for
both the point count method and the transect walk method was recorded. In terms
of Shannon diversity index (H’), an increase was noted in point count method
(t-value = 5.11; t-crit = 1.96; p-value = 3.87E-7; α = 0.05) while a
significant increase in transect walk method (t-value = 3.72; t-crit = 2.06;
p-value = 1.08E-3; 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 Low to Moderate (L – M) abundance. In terms of species richness,
different wetland habitats were generally observed with Very High (VH) 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) and Low to Moderate (L – M)
abundance of avifauna species of conservation importance; and were generally
utilized by Low to Moderate (L – M) number of species (Table 25).
5.2.3.4 Noise Levels
Noise
levels LAeq (30 min) recorded on 4 December 2024 (daytime)
and 18 December 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.