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 9 July 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 19:11, 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 8
July
2024 and started around 18:11 (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
(4), Little Egret Egretta garzetta (11) and
Great Egret Ardea alba (1)
were observed in pre-roost aggregate (PRA) around 18:24
at the mudflat east side ANR1 of the Project boundary while individuals of Chinese
Pond Heron Ardeola bacchus
(2), Little
Egret Egretta garzetta
(6)
and Great Egret Ardea alba (2)
were concurrently noted at the mudflat northeast side ANR2 of the Project boundary
(Table 17).
For the final night roost
at around 19:14, individuals of Chinese
Pond Heron Ardeola bacchus
(21) and Little Egret Egretta garzetta (13) 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
(13), Little Egret Egretta garzetta (8) and Great Egret Ardea
alba (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 8 July 2024 in concurrence with the
construction phase monthly monitoring of the pre-identified active night
roosts. Noise monitoring started at 19:14 and lasted for 30 minutes, until 19:44.
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 July 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.
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
13 June 2024 (daytime) and 19 June 2024 (night-time) which started at around
07:15 and 19:09. 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 25 July 2024
(daytime) and 8 July 2024 (night-time) which started at around 07:15 and 19:41,
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 666
avifauna individuals were recorded in the monitoring area during the July 2024
monitoring period, of which 489 individuals were recorded from the point count
method and 177 individuals from the transect walk method. Relative to the July 2017
baseline data (point count method = 165; and transect walk = 36), significant
increases were noted for both the point count and transect walk methods.
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 666 avifauna
individuals recorded in the monitoring area during the July 2024 monitoring
period, 376 individuals (point count method = 280 individuals; transect walk
method = 96 individuals) were of
conservation importance. With reference to July 2017 data, (point count
method = 80; and transect walk = 8), significant increases were noted for both point
count and 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 41 avifauna
species (species richness) were recorded during the July 2024 monitoring
period, of which, 39 species were recorded by the point count method while 26 species
were noted by the transect walk method. Relative to the baseline data (point
count method = 26 species; transect walk method = 18 species), increases in
total species richness for both transect walk count and point count methods
were recorded. In terms of Shannon diversity index (H’) values, current result
in point count method showed a slight increase (t-value = 0.77; t-crit = 1.97;
p-value = 0.44; α = 0.05) relative to the baseline reference value. The current
results in the transect walk method also showed a slight increase (t-value = 0.37;
t-crit = 2.00; p-value = 7.09E-1; 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 41 avifauna species
identified during the July 2024 monitoring period, 16 species were of
conservation importance (point count method = 16 species; transect walk method
= 10 species). Meanwhile, relative to the baseline values in July 2017 (point
count method = 5 species; transect walk method = 3 species), a 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’), an increase was noted in point count method (t-value = 3.22; t-crit = 1.97;
p-value = 0.0015; α = 0.05) while a significant increase in transect walk
method (t-value = 2.47; t-crit = 2.20; p-value = 3.09E-2; 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 Very Low (VL) abundance. In terms of species richness, different wetland
habitats were generally observed with Low (L) and Moderate (M) 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 (VL) number of
species (Table 25).
5.2.3.4 Noise Levels
Noise levels LAeq (30 min) recorded on 25 July 2024(daytime) and 8 July
2024(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.