With reference
to the Pre-construction Ardeid Night Roost survey (Feburary 2017) 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.
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.
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 25 March 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.
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 18:39, 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.
The monitoring
activity was conducted on 25
March 2024 and started around 17:36 (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 Little Egret Egretta garzetta (2) were observed in pre-roost
aggregate (PRA) around 18:09 at the mudflat east side ANR1 of the Project
boundary while individuals of Chinese Pond Heron Ardeola bacchus (2) and
Great Egret Ardea alba (3) were concurrently noted at the mudflat
northeast side ANR2 of the Project boundary (Table 17).
For the final
night roost at around 18:23, individuals of Chinese Pond Heron Ardeola
bacchus (8) 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 (10), Great Egret Ardea alba (23) and Little Egret Egretta
garzetta (12) 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.
Noise
monitoring activities were conducted on 25 March 2024 in
concurrence with the construction phase monthly monitoring of the
pre-identified active night roosts. Noise monitoring started at 18:23 and
lasted for 30 minutes, until 18:53.
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.
No unpredicted
indirect ecological impacts that arose from the project were noted during the
current monitoring period.
Two active
ardeid night roost areas (ANR1 and ANR2) were observed within the Survey Area
during the March 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.
Both noise
levels at each of the monitoring stations were below the action and limit
levels.
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.
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.
Avifauna
surveys on the different wetland habitats using the transect count and point
count methods were conducted last 4
March 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.
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,
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 March 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 07:15 had results
presented in Section 5.2.3.3.
An
overall total of 1076 avifauna individuals were recorded in the monitoring area
during the March 2024 monitoring period, of which 666 individuals were recorded
from the point count method and 410 individuals from the transect walk method.
Relative to the March 2017 baseline data (point count method = 607; and
transect walk = 170), increase in both point count and transect walk method were
observed.
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.
Of
the 1076 avifauna individuals recorded in the monitoring area during the March
2024 monitoring period, 599 individuals (point count method = 345 individuals;
transect walk method
= 254 individuals) were of conservation importance. With
reference to March 2017 data, (point count method = 510; and transect walk = 44),
a decrease was noted for point count method, while an increase in transect walk
method was observed. Details of these findings are summarized in Table 21.
One
exceedance in Action Level was recorded for the decline in Abundance of Species
of Conservation Importance in the point count method.
A
total of 58 avifauna species (species richness) were recorded during the March
2024 monitoring period, of which, 52 species were recorded by the point count
method while 40 species were noted by the transect walk method. Relative to the
baseline data (point count method = 45 species; transect walk method = 36
species), increases in total species richness for both transect walk count and point
count methods. In terms of Shannon diversity index (H’) values, current result
in point count method showed a significant increase (t-value = 8.84; t-crit = 1.96;
p-value = 3.55E-18; α = 0.05) relative to the baseline reference value. The current
results in the transect walk method showed an increase (t-value = 1.28; t-crit
= 1.97; p-value = 2.02E-01; 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.
Of
the 58 avifauna species identified during the March 2024 monitoring period, 26
species were of conservation importance (point count method = 23 species;
transect walk method = 20 species). Meanwhile, relative to the baseline values
in March 2017 (point count method = 21 species; transect walk method = 8
species), significant 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’), increases in point count method (t-value
= 5.83; t-crit = 1.96; p-value = 8.09E-9; α = 0.05) and transect walk method (t-value
= 3.98; t-crit = 2.00; p-value = 1.82E-4; α = 0.05) were noted 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.
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.
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 High to Very High (H - VH)
number of species (Table 24).
Majority
of the different wetland habitats had 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).
Noise
levels LAeq (30 min) recorded on 4 March 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.