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 3 February 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 18:22, 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 3 February
2026 and started around 17:12 (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 (5), Great
Egret Ardea alba (1) and Little Egret Egretta garzetta
(1) were observed in pre-roost aggregate (PRA) around 17:59 at the mudflat east
side ANR1 of the Project boundary while individuals of Chinese Pond Heron Ardeola bacchus (5), Great
Egret Ardea alba (1), Little Egret Egretta garzetta
(1) and Grey Heron Ardea cinerea (3) were concurrently noted at the
mudflat northeast side ANR2 of the Project boundary (Table 17).
For the final night roost at around 18:22,
individuals of Chinese Pond Heron Ardeola bacchus (8), Little Egret Egretta garzetta (1) and Grey Heron Ardea cinerea (3) 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
(3), Great Egret Ardea alba (1), Little Egret Egretta garzetta (3) and Grey Heron Ardea cinerea (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 3 February
2026 in concurrence with the construction phase monthly monitoring of the
pre-identified active night roosts. Noise monitoring started at 18:22 and
lasted for 30 minutes, until 18:42.
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 February 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 12 February
2026 (daytime) which started at around 07:15 and 3 February 2026 (night-time)
which started around 18:26. 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 12 February 2026 (daytime) which
started at around 07:15 and 3 February 2026 (night-time) which started at
around 18:30 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 1012 avifauna individuals were recorded in the
monitoring area during the February 2026 monitoring period, of which 658 individuals
were recorded from the point count method and 354 individuals from the transect
walk method. Relative to the February 2017 baseline data (point count method = 642;
and transect walk = 2), a slight increase was noted for point count method and a
significant increase 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 1012 avifauna individuals recorded in the monitoring area during
the February 2026 monitoring period, 710 individuals (point count method = 452
individuals; transect walk method = 258 individuals) were of conservation
importance. With reference to February 2017 data, (point count method = 447;
and transect walk = 2), a slight increase was noted for point count method and a
significant increase for 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 65 avifauna species (species richness) were recorded during
the February 2026 monitoring period, of which, 62 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 = 58 species; transect walk
method = 1 species), a slight increase in total species richness for the point
count method and a significant increase for 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 = 0.05; t-crit = 1.96; p-value = 9.58E-01;
α = 0.05) relative to the baseline reference value. The current results in
the transect walk method also showed a significant increase (t-value = 52.9;
t-crit = 1.97; p-value = 4.91E-170; 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 65 avifauna species identified during the February 2026 monitoring
period, 30 species were of conservation importance (point count method = 28
species; transect walk method = 18 species). Meanwhile, relative to the
baseline values in February 2017 (point count method = 26 species; transect
walk method = 1 species), a slight increase in number of species with
conservation importance was recorded for point count method and a significant
increase for transect walk method. In terms of Shannon diversity index (H’),
there is a decrease in point count method (t-value = 1.57; t-crit = 1.96;
p-value = 1.16E-01; α = 0.05) and a significant increase in transect walk
method (t-value = 42.3; t-crit = 1.97; p-value = 4.17E-118; 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
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) abundance
of avifauna species of conservation importance; and were generally utilized by
Moderate (M) number of species (Table 25).
5.2.3.4 Noise
Levels
Noise
Levels
Noise levels LAeq (30 min) recorded on 12 February
2026 (daytime) and 3 February 2026 (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.