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.
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 7x 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 17 October
2023.
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 18:50, 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 17 October 2023 and started
around 16:58 (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)
and Little Egret Egretta garzetta (2) were observed in pre-roost aggregate (PRA) around 17:50 at the
mudflat east side ANR1 of the Project boundary while other individuals of
Chinese Pond Heron Ardeola bacchus (4) were concurrently noted at the mudflat
northeast side ANR2 of the Project boundary (Table 17).
For the final night roost at around 18:30, individuals of Chinese
Pond Heron Ardeola bacchus
(5) 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 Chinese
Pond Heron Ardeola bacchus
(4) 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 17 October 2023 in
concurrence with the construction phase monthly monitoring of the
pre-identified active night roosts. Noise monitoring started at 18:30 and
lasted for 30 minutes, until 19:00.
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 October 2023 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 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 17 October 2023
(daytime and night-time) which started at around 07:00. 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 07:30. 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 17 October 2023 (daytime),
which started around 07:00, 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 07:00 had results presented in Section
5.2.3.3.
An overall total of 568
avifauna individuals was recorded in the monitoring area during the October
2023 monitoring period, of which 516 individuals were recorded from the point
count method and 52 individuals from the transect walk method. Relative to the October
2016 baseline data (point count method = 157; and transect walk = 51), increase
in both point count method and transect walk method was 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 568 avifauna
individuals recorded in the monitoring area during the October 2023 monitoring
period, 323 individuals (point count method = 314 individuals; transect walk
method = 9
individuals) were of conservation importance. With reference to October 2016
data, (point count method = 107; and transect walk = 35), increase in point
count method and decrease in transect walk method was also observed. 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.
A total of 36 avifauna
species (species richness) were recorded during the October 2023 monitoring
period, of which, 33 species were recorded by the point count method while 15 species
were also noted by the transect walk method. Relative to the baseline data
(point count method = 32 species; transect walk method = 13 species), increase
in total species richness for point count method and transect walk method were
noted. In terms of Shannon diversity index (H’) values, current result in point
count method showed slightly decrease (t-value = 4.47; t-crit = 1.97; p-value
=0.0000103; α = 0.05) relative to the baseline reference value. The current
results in the transect walk method showed slightly increase (t-value = 1.898;
t-crit = 1.98; p-value =0.06; 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 36 avifauna species
identified during the October 2023 monitoring period, 12 species were of
conservation importance (point count method = 10 species; transect walk method
= 4 species). Meanwhile, relative to the baseline values in October 2016 (point
count method = 13 species; transect walk method = 3 species), a decrease in the
number of species with conservation importance were recorded from point count
method and an increase was recorded in the transect walk method. In terms of
Shannon diversity index (H’), significant decrease in point count method
(t-value = 7.69; t-crit = 1.97; p-value =0.00; α = 0.05) and an increase
in transect walk method (t-value = 1.13; t-crit = 2.18; p-value =0.28; α =
0.05) was 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 very low (VL) abundance. In terms of species richness, different wetland
habitats were generally observed with very low (VL); and very low to low (VL-L)
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 also generally utilized by very low (VL); and
very low to low (VL-L) number of species (Table 25).
Noise levels LAeq (30 min) recorded on 17 October 2023 (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.