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 4 November 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 16:47,
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 4 November
2024 and started around 16:44 (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 (6), Great Egret Ardea alba (1) and Grey Heron Ardea
cinerea (1) were observed in pre-roost aggregate (PRA) around 17:23 at the
mudflat east side ANR1 of the Project boundary while individuals of Chinese
Pond Heron Ardeola bacchus
(3), Great Egret Ardea alba (6), Little Egret Egretta garzetta (2) and Grey
Heron Ardea cinerea (2) were concurrently noted at
the mudflat northeast side ANR2 of the Project boundary (Table 17).
For the final night roost at around 17:41,
individuals of Chinese Pond Heron Ardeola bacchus (35) and Great Egret Ardea
alba (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
(8), Little Egret Egretta garzetta
(4), Great Egret Ardea alba (6) and Grey Heron Ardea cinerea (2) 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 4
November 2024 in concurrence with the construction phase monthly monitoring of
the pre-identified active night roosts. Noise monitoring started at 17:41 and
lasted for 30 minutes, until 18:11.
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 November 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 was conducted
last 5 November 2024 (daytime) which started at around 07:15. 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 5 November 2024 (daytime) which
started at around 07:15, 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 08:00 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 817 avifauna
individuals were recorded in the monitoring area during the November 2024
monitoring period, of which 613 individuals were recorded from the point count
method and 204 individuals from the transect walk method. Relative to the November
2016 baseline data (point count method = 608; and transect walk = 125), an 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 817 avifauna individuals recorded
in the monitoring area during the November 2024 monitoring period, 444
individuals (point count method = 340 individuals; transect walk method = 104
individuals) were of conservation importance. With reference to November 2016
data, (point count method = 394; and transect walk = 59), a decrease was noted
for the point count method, while a notable increase was noted for the transect
walk method. 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 November 2024 monitoring period, of which,
53 species were recorded by the point count method while 39 species were noted
by the transect walk method. Relative to the baseline data (point count method
= 48 species; transect walk method = 20 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 = 2.59; t-crit = 1.96; p-value = 0.0097; α =
0.05) relative to the baseline reference value. The current results in the
transect walk method showed an increase (t-value = 4.64; t-crit = 1.97; p-value
= 5.38E-6; 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 November 2024 monitoring period, 24 species were of conservation
importance (point count method = 20 species; transect walk method = 14
species). Meanwhile, relative to the baseline values in November 2016 (point
count method = 20 species; transect walk method = 7 species), an increase in
the number of species with conservation importance for transect walk method was
recorded. In terms of Shannon diversity index (H’), a slight increase was noted
in point count method (t-value = 0.44; t-crit = 1.96; p-value = 0.66; α =
0.05) while a significant increase in transect walk method (t-value = 4.84;
t-crit = 1.98; p-value = 3.93E-6; 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 (L)
abundance. In terms of species richness, different wetland habitats were
generally observed with Low (L) and High to Very High (H – 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) abundance of avifauna species of conservation
importance; and were generally utilized by Low (L) number of species (Table 25).
5.2.3.4 Noise Levels
Noise levels LAeq
(30 min) recorded on 5 November 2024 (daytime) 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.