9               ECOLOGICAL MONITORING

Monitoring of Measures to Minimise Disturbance to Water Birds in Ng Tung River, Sheung Yue River, Shek Sheung River and Long Valley

Monitoring Requirements and Protocol

9.1         As required under Section 12.3.2.5 of Updated EM&A Manual, where development under the NDAs project is undertaken within 200m (the maximum distance at which it is predicted there may be some disturbance, and hence a reduction in numbers, of large waterbirds) of Sheung Yue River and Long Valley, weekly transect at both high and low tides should be followed (It is considered high tide when the tidal levels are above 1.5m and low tide when the tidal levels are below 1.5m at Tsim Bei Tsui Station).

9.2         The purpose of the survey was to identify and enumerate all bird species utilizing the river channels and Long Valley Nature Park (LVNP) and identify any sources of actual or potential disturbance to birds due to construction activities throughout the construction period according to Methodology specified in Table 12.1 in Updated EM&A Manual.

9.3         Monitoring in Long Valley should follow the methodology adopted by the regular HKBWS bird monitoring programme in order to obtain comparable results and complete coverage of the area in the shortest time possible.

Monitoring Frequency

9.4         High tide and low tide avifauna monitoring is required to be carried out on weekly basis.

Additional night-time avifauna monitoring in Long Valley is required to be carried out twice monthly from September to April.

Date of avifauna monitoring:

2nd , 3rd , 8th, 9th, 16th ,23rd , 24th, 28th, 29th December 2021

Date of night-time monitoring:

9th, 24th December 2021

 

Monitoring Location

9.5         The avifauna monitoring was carried out at Ng Tung River, Sheung Yue River and Long Valley in reporting month according to construction works. The transect routes in the Reporting Month were as follows:

       T1. Ng Tung River

       T2. Ng Tung River

       T3. Sheung Yue River

       T5. Long Valley

As the sensitive receivers (large waterbirds) are easily visible, the transect route will only need to follow one bank of the rivers.

9.6         The location of Transects T1, T2, T3 and T5 is shown in Figure 9 for reference.


 

Monitoring Parameters

9.7         The monitoring parameters and survey methodology for each transect are described below:

       Abundance of birds

       Types of habitat of which birds in use

       Notable bird behaviours such as roosting, feeding, nesting and presence of juveniles

       Birds heard through birdcalls that could not be located would be marked as “heard”, while birds flying over the survey area would be marked as “flight”. Species of conservation significance would be specified.

9.8         Other information at the time of survey such as weather condition, tidal condition, tide level and noticeable natural or anthropogenic activities would be documented.

9.9         For Avifauna survey, Ornithological nomenclature would make reference to The Avifauna of Hong Kong (Carey et al. 2001), The Birds of Hong Kong and South China (Viney et al. 2005), and the most recent updated list from other sources (e.g. Hong Kong Bird Watching Society).

Monitoring Result

9.10     In total, 67 species of birds were recorded during the bird surveys within assessment area. Among the recorded birds, there were 29 species of waterbirds. The detailed list of waterbirds and all recorded birds are shown in Appendix L1k and L1l respectively.

9.11     Among the four transects, the transect T5 had a higher species diversity and abundance due to its diverse habitat types within Long Valley. Species such as Ardeola bacchus and Egretta garzetta were commonly found roosting and foraging at wetland habitats such as agricultural lands and shallow water habitats.

9.12     Along the transect T5 in Long Valley, species with conservation interest such as Himantopus himantopus, which is a passage migrant, and Tringa nebularia which is a passage migrant and winter visitor, were commonly observed in swallow water habitat. In addition, winter visitor species with conservation interest such as Recurvirostra avosetta and Platalea minor, were observed in shallow water habitat in the reporting month.

9.13     Construction works were observed in T5 in the reporting month.

9.14     Transect T3 was conducted along the Sheung Yue River. Bird species such as Ardeola bacchus and Egretta garzetta were commonly observed feeding and roosting on the river bank and river bed. Construction works were observed beside Sheung Yue River.

9.15     Transect T1 and T2 are located at Ng Tung River. Ardeola bacchus and Egretta garzetta were commonly found feeding and roosting along the Ng Tung River. Fishing activities were observed at both T1 and T2, while construction activities were observed beside T2 during the avifauna monitoring. Noise-producing anthropogenic sources observed during avifauna monitoring includes ground investigation works of remaining phase near T1 and T2.

9.16     Avifauna monitoring in construction phase was conducted during the reporting month and the detailed results are attached in Appendix L1.

 

Monitoring of Measures to Minimise Impacts to Ma Tso Lung Stream and Siu Hang San Tsuen Stream, and Long Valley

Monitoring Requirements and Protocol

9.17     As required under Section 12.3.2.14 of Updated EM&A Manual, aquatic faunal monitoring should be carried out during the construction phase.

9.18     Larger organisms such as fish should be monitored by direct counting, while kick-netting and sweep-netting should be used for invertebrate sampling. There should be three replicates for invertebrate sampling at each sampling point. For kick-netting, the net should be placed with the opening facing the water current, and the substrate should be disturbed by kicking to dislodge organisms from the stream bed. Sweep-netting should be conducted when kick-netting is not feasible, such as in area with no water current. Small organisms that could not be identified with naked eye should be brought to the laboratory for identification under the dissecting microscope.

Monitoring Frequency

9.19     Quantitative aquatic fauna replicate surveys of stream fauna is required to be carried out on monthly basis during wet season. Three replicates for invertebrates sampling and direct counting of fish fauna should be performed respectively.

Monitoring Location

9.20     During wet season, the monitoring location required to be carried out in Ma Tso Lung Stream according to construction works are as follow:

             MS_01

             MS_02

             MS_03

             MS_04

             MS_05

             MS_06

             MS_07

             MS_08

             MS_09

             MS_10

             MS_11

             MS_12

             MS_13

             MS_14

             MS_15

9.21     The location of Monitoring Stations shown in Figure 10 for reference.

Monitoring Parameters

9.22     The monitoring parameters and survey methodology for each monitoring station are described below:

       Species composition

       Abundance

       Distribution for invertebrates and fish fauna

       Species of conservation significance would be specified

9.23     Other information at the time of survey such as weather condition and noticeable natural or anthropogenic activities would be recorded.

Monitoring Status

 

9.24     According to the Updated EM&A Manual, quantitative aquatic fauna replicate surveys of stream fauna is required to be carried out on monthly basis during wet season. During the reporting Month, no aquatic fauna replicate surveys was carried out.

Monitoring of Measures to Minimise Impacts on Ecological Sensitive Habitats from Disturbance and Pollution

Monitoring Requirements and Protocol

9.25     As required under Section 12.3.2.17 of Updated EM&A Manual, monitoring of measures to minimize impacts should be carried out during the construction phase.

9.26     The purpose of survey is to monitor the effectiveness of measures to minimize impacts on ecologically sensitive habitats from disturbance and pollution by standard faunal transect surveys.

Mammal survey

9.27     Mammal survey should be performed during both day and night times, in areas along the transect routes which may potentially be utilized by terrestrial mammals. Field signs such as droppings, footprints, diggings and burrows left by larger terrestrial mammals should be observed. Mammals directly observed should be recorded, and identification should be made as accurate as possible form the field signs observed.

9.28     Bat survey should be conducted along the transect routes shortly after sunset, with the use of a bat detector to record the echolocation calls. The relative abundance of the species encountered should be estimated with reference to the baseline monitoring results, i.e. using a scale from one (species recorded within transect routes) to three (dominant species within transect routes), for comparison between baseline results and the current monitoring results. Nomenclature of mammal should be based on Shek (2006).

Herpetofauna survey (Amphibians and Reptiles)

9.29     Amphibian surveys should be conducted whenever possible on evenings following or during periods of rainfall, focusing on areas suitable for amphibians (e.g. forest, shrublands, grasslands, streams, ponds, marshes, etc.). Calling amphibians should be recorded, supplemented by visual observation of eggs, tadpoles, adult frogs, and toads.

9.30     Active searching of appropriate microhabitats such as stones, pond bunds, crevices and leaf debris should be performed mainly. Observation of exposed, basking and foraging reptiles should also be conducted. Nomenclature of amphibian and reptile should be based on Chan et al. (2005) and Karsen et al. (1998), respectively.

Insect survey (Butterfly and Dragonfly)

9.31     Butterflies and dragonflies observed along the transects should be identified and counted. Preferable habitats of the insects such as watercourses, fishponds, and vegetated areas should be observed with special attention. Nomenclature and protection status of the species should be based on Lo et al. (2005) for butterflies and Tam et al. (2011) for dragonflies

Monitoring Frequency

9.32     Monitoring surveys of ecological sensitive receivers such as mammals, insects (butterflies and dragonflies), and herpetofauna should be undertaken on a monthly bases.

Date of Monitoring surveys of ecological sensitive receivers:

10th , 15th December 2021

 

Monitoring Location

9.33     The transect routes in the Reporting Month according to construction works are as follows:

           T1. Ma Tso Lung riparian zone and associated wetland habitats;

           T1. Green belt areas E1-8, D1-8 and G1-3 in KTN NDA;

           T1. AGR one C2-4 and C2-2 in KTN NDA;

           T1. Area north of Ng Tung River;

           T3. Area west of Siu Hang San Tsuen Stream

           T4. South side of Fanling Highway and Castle Peak Road in the vicinity of Pak Shek Au;

           T5. Area west and east of the southern limit of the FLN NDA work area; and

           T6. Areas in the western part of KTN

9.34     The location of Transects is shown in Figure 11 for reference.

Monitoring Parameters

9.35     The monitoring parameters and survey methodology for each transect are described below:-

       Species composition

       Abundance

       Distribution for fauna observed

       Species of conservation significance would be specified

Monitoring Result

Mammal

9.36     During the survey, a total of 4 mammal species were recorded from transects T1, T3, T4, T5 and T6. A total of 2 species of conservation importance were recorded, namely bats Pipistrellus abramus and Cynopterus sphinx.

9.37     Domestic cat, Felis catus was found at T1and T5. Domestic dog, Canis lupus familiaris, was found at T1, T5 and T6, where associated with human settlements.

9.38     Echolocation calls of bats were recorded with a bat detector. The bat detector would list out possible bat species having similar echolocation calls in pattern and frequency. The structure of the echolocation calls from the recordings was later analysed to identify species as far as possible (the lack of literature on echolocation call structure makes the field identification of some bat species in Hong Kong difficult, and some species could only be identified to genus level, or remain unidentified from the recordings).

9.39     Identification of bat species encountered in the surveys was made with consideration to the possible bat species suggested by the bat detector, the distribution of the suggested bat species in Hong Kong, previous records of bat species in the EIA Report and Baseline Monitoring Report, and the structure of echolocation calls of the recordings (including call structure, frequency, duration, inter pulse interval etc., with reference to relevant literatures).

9.40     Pipistrellus abramus was recorded with FM/QCF call structure and frequency around 45 kHz to 68 kHz (Ma et al., 2010, p.319). The above characteristics were further compared with data from relevant literatures to confirm the identities. References were also made to Tong (2016).

9.41     Bat species, Cynopterus sphinx was observed roosting in the tent-shaped shelter under fronds of Chinese Fan-palm during during the monitoring at T1, T4 and T6. Pipistrellus abramus was recorded in flight at nighttime at all of the transects.

Herpetofauna (Amphibians and Reptiles)

9.42     Along the transects, a total of 5 herpetofauna species were observed. No species of conservation importance were recorded. Species including frogs, toads, lizards and geckos were recorded near wetland habitats and watercourse. Transect T1 had higher species diversity than other transects, whereas T5 as the highest number of observations due to the dominance of Bufo melanostictus.

Insects (Butterfly and Dragonfly)

9.43     During the insect survey, a total of 15 butterfly species and 1 odonata species were recorded from the transects, with all butterfly species being common or very common. Transect T1 had higher butterfly species diversity than other transects.

9.44     T1 had recorded the most species among all transects. All of the dragonfly species recorded, were common and abundant in Hong Kong. No species of conservation importance was recorded.

9.45     Ecological sensitive receivers such as mammals, insects (butterflies and dragonflies), and herpetofauna monitoring in construction phase was conducted during the reporting month and the results are attached in Appendix L4 to L7.

9.46     Since activities of odonata can fluctuates with environmental conditions, in addition to potential effects of surrounding human activities and alteration to their natural habitat (vegetative clearance and construction works outside of the projects observed at various transect), more attention should be paid to future monitoring results, potential sources of disturbance and other relevant ecological data.

9.47     For the monitoring conducted on 10th December 2021 on Transect T/5, a section of the transect route was found located within private property, and was not accessible. Another section on transect T5 was found blocked by new accumulation of fallen trees. The inaccessible part are shown in Photo 1 and Photo 2 below. The adjusted accessible transect route is shown in Figure 11.

 

WhatsApp Image 2021-08-10 at 23

WhatsApp Image 2021-05-20 at 15

Photo 1. Inaccessible part of transect T5 located within private property.

Photo 2. Inaccessible part of transect T5 blocked by the fallen trees.

Results and Observation

Details of the Influencing Factors

Major Activities

9.48     During the survey of Monitoring of Measures to Minimise Disturbance to Water Birds in Sheung Yue River and Long Valley, anthropogenic activities including soil turning with excavator and other construction activities were observed in Long Valley. Construction works were observed beside Sheung Yue River.

9.49     The anthropogenic activities affected only a small area of habitat in Long Valley during the monitoring and would only pose minor disturbances to the birds. Acridotheres cristatellus and Bubulcus coromandus were observed foraging near the excavators.

9.50     During the survey of Monitoring of Measures to Minimise Disturbance to Water Birds in Ng Tung River, anthropogenic activities including construction works beside T2, and recreational fishing by fishing rod at both T1 and T2 were observed.

9.51     During the survey of Monitoring of Measures to Minimise Impacts on Ecological Sensitive Habitats from Disturbance and Pollution, construction activities NOT under this project were observed at T3 and T5. Dust plumes and considerable alteration of vegetative habitat were observed as a result of these activities.

Weather Conditions

9.52     According to the observation during survey, temperature and the rain flow record in the Reporting Month (Reference: http://www.weather.gov.hk/wxinfo/pastwx/metob202112.htm), weather condition might pose influence towards the monitoring result.

The detailed Ecological monitoring results are attached in Appendix L.

Reference

Ma, J., Jones, G., Zhu, G. J., & Metzner, W. (2010). Echolocation behaviours of the Japanese pipistrelle bat Pipistrellus abramus during foraging flight. Acta Theriologica, 55(4), 315-332.

 

Tong, C. F. (2016). Distribution and preference of landscape features and foraging sites of insectivorous bats in Hong Kong urban parks. (Master dissertation)