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 contractors 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 22 April 2026.
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 18:58, 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 22 April 2026 and started around 17:45 (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
(1) and Great Egret Ardea alba (1) were observed around 18:32 at the
mudflat east side ANR1 of the Project boundary while individuals of Chinese
Pond Heron Ardeola bacchus
(1), Great Egret Ardea alba (5), Little Egret Egretta garzetta (2) and Grey Heron Ardea cinerea (1)
were concurrently observed in pre-roost aggregate (PRA) 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 (13), Great Egret Ardea alba (1) and
Little Egret Egretta garzetta (2) 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 (9), Great Egret Ardea alba (7), Little
Egret Egretta garzetta (3) 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 22
April 2026 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 April 2026 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 22 April
2026 (daytime + night-time) which started at around 07:15 and 19:00
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. 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, r
respectively, of this EM&A report. The parameter as shown in was recorded
at each of the point count locations.
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 Table
19 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 22 April 2026 (daytime and night-time) which started at around 07:15 and
19:00 respectively, 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 423 avifauna individuals were recorded in the
monitoring area during the April 2026 monitoring period, of which 298
individuals were recorded from the point count method and 125 individuals from
the transect walk method. Relative to the April 2017 baseline data (point count
method =298; and transect walk = 47), point count numbers remained the same,
where an increase was noted for 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 423 avifauna
individuals recorded in the monitoring area during the April 2026 monitoring
period, 187 individuals (point count method = 140 individuals; transect walk
method = 47 individuals) were of conservation importance. With reference to
April 2017 data, (point count method = 200; and transect walk = 1), a decrease
was noted for point count method and an increase for transect walk method.
Details of these findings are summarized in Table 21.
No Action / Limit
exceedance was recorded for the abundance of Species of Conservation Importance
in both 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 50 avifauna
species (species richness) were recorded during the April 2026 monitoring
period, of which, 46 species were recorded by the point count method while 29
species were noted by the transect walk method. Relative to the baseline data (point
count method = 41 species; transect walk method = 13 species), an increase in
total species richness for both point count method and transect walk method
were recorded. In terms of Shannon diversity index (H’) values, current result
in point count method showed a slight increase (t-value = 1.34; t-crit = 1.96;
p-value = 1.82E-01; α = 0.05) relative to the baseline reference value.
The current results in the transect walk method also showed an increase
(t-value = 5.71; t-crit = 1.99; p-value = 2.47E-07; 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 species diversity of all avifauna species in
both point count and transect walk method.
5.2.3.2.2 Avifauna Species of Conservation
Importance
Of the 50 avifauna species
identified during the April 2026 monitoring period, 20 species were of
conservation importance (point count method = 17 species; transect walk method
= 11 species). Meanwhile, relative to the baseline values in April 2017 (point
count method = 13 species; transect walk method = 1 species), an increase in
number of species with conservation importance was recorded for both point
count method and transect walk method. In terms of Shannon diversity index
(H’), there is a slight decrease in point count method (t-value = 0.62; t-crit
= 1.97; p-value = 5.35E-01; α = 0.05) and a significant increase in transect
walk method (t-value = 15.1; t-crit = 2.01; p-value = 1.34E-19; α = 0.05)
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 species diversity of
avifauna species with conservation importance in both point count and 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 High (H) 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 to Low (VL –
L) number of species (Table 25).
5.2.3.4 Noise Levels
Noise levels LAeq (30 min) recorded on 22 April 2026 (daytime and 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.