5.1.3.2
Noise
Monitoring
Noise monitoring activities were conducted on 12 April
2023 in concurrence with the construction phase monthly monitoring of the
pre-identified active night roosts. Noise monitoring started at 18:27 and
lasted for 30 minutes, until 18:57.
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 5.3.
5.1.4
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.
5.1.5
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.
5.1.6
Summary
5.1.6.1
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 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,
Little Egret Egretta garzetta,
Great Egret Ardea alba, and Grey Heron Ardea cinerea.
5.1.6.2
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
5.2.1
Monitoring Requirement
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
Monitoring Methodology
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 14 April
2023 (daytime) and 12 April 2023 (night-time) which started at around 07:30 and
17:42. 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.
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.
5.2.3
Monitoring Results
Results of the avifauna survey on the different
habitats within the monitoring area using the transect count and point count
methods as conducted last 14 April 2023 (daytime) and 12 April 2023
(night-time), which started around 07:30, 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 07:30 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 297 avifauna individuals was recorded in the monitoring area during the April
2023 monitoring period, of which 240 individuals were recorded from the point count method and 57 individuals from the transect walk method. Relative to the April
2017 baseline data (point count method = 298; and transect walk = 47), decrease
in point count method and increase in transect walk method was observed.
Details of these findings are summarized in Table 5.5.
5.2.3.1.2 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.
5.2.3.1.3Avifauna Species of Conservation
Importance
Of the 297 avifauna individuals
recorded in the monitoring area during the April 2023 monitoring period, 108 individuals (point count method = 93 individuals; transect walk method = 15 individuals) were of conservation importance. With reference
to April 2017 data, current results showed decrease in total abundance for the
point count method and increase for the transect walk method. Details of these
findings are summarized in Table 5.6.
5.2.3.2
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.
5.2.3.3
Diversity
(Species Richness[1] and
Shannon Diversity Index[2])
5.2.3.3.1 All Avifauna
Species
A total of 38 avifauna species (species richness) were
recorded during the April 2023 monitoring period, of which, 34 species were
recorded by the point count method while 20 species were noted by the transect
walk method. Relative to the baseline data (point count method = 41 species;
transect walk method = 13 species), decrease in total species richness for the
point count method and increase for transect walk method were noted. In terms of Shannon
diversity index (H’) values, current result in point count method showed no
significant difference (t-value = 0.02; t-crit = 1.97; p-value =0.98; α =
0.05) relative to the baseline reference value. Conversely, current results in
the transect walk method showed a significant increase (t-value = 3.96; t-crit
= 1.99; p-value =0.00; α = 0.05) from baseline reference value. Details of these findings
are summarized in Table 5.7, Appendix F.6.1, and Appendix F.6.2.
5.2.3.3.2 No Action / Limit
exceedance was recorded for the decline in species diversity of all avifauna
species in the point count / transect walk method.
5.2.3.3.3 Avifauna Species of
Conservation Importance
Of the 38 avifauna species identified during the April
2023 monitoring period, 16 species were of conservation importance (point count
method = 13 species; transect walk method = 6 species). Meanwhile, relative to
the baseline values in April 2017 (point count method = 13 species; transect
walk method = 1 species), no changes 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’), no significant
difference in point count method (t-value = 0.23; t-crit = 1.99; p-value =0.82;
α = 0.05) and a significant increase in transect walk method (t-value = 7.42;
t-crit = 2.13; p-value =0.00; α = 0.05) was noted relative to the baseline
reference values. Details of these findings
are summarized in Table 5.8, and Appendix F.6.3.
5.2.3.4
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.
5.2.3.5
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.
5.2.3.5.1 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 very low (VL); and very low to low (VL-L) number of species (Table 5.9).
5.2.3.5.2 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 5.10).
5.2.3.6
Noise
Levels
Noise levels LAeq
(30 min) recorded on 14 April 2023 (daytime) and 12 April 2023 (night-time) from
each of the point count locations during the ecological bird monitoring are
shown in Table 5.11.
5.2.4 No Action / Limit exceedance was recorded
for noise levels at all stations for the ecological monitoring of birds in the
reporting month.