3.3.11 Transect 4 was the most species-rich (13 species), possibly due to the presence of a few flowering shrubs and a raised bund providing higher ground than the surroundings. Low floral diversity, the lack of woodland and (possibly) deleterious impacts of insecticide applications to crops may account for the low butterfly diversity in the middle of Long Valley.

Amphibians

3.3.12 The following tables provide a semi-quantitative assessment of individuals present, detected by vocalisations and/or spotlighting. I = 1 individual; II = 2-5 individuals; III = 6-10 individuals; IV = 11-20 individuals; V = >20 individuals.

Table 3.8 Amphibian species recorded at transect 1

Species/date

15.6.00

22.6

23.7

29.7

11.8

23.8

3.9

12.9

15.11

29.11

6.4.01

10.4

29.4

5.5

8.5

21.5

30.5

Bufo melanosticta

I

II

II

I

I

III

Kaloula pulchra

I

Polypedates megacephalus

I

I

I

Rana guentheri

I

II

II

II

I

II

II

Rana limnocharis

II

V

III

II

II

II

I

I

I

I

Table 3.9 Amphibian species recorded at transect 2

Species/date

15.6.00

22.6

23.7

29.7

11.8

23.8

3.9

12.9

15.11

29.11

6.4.01

10.4

29.4

5.5

8.5

21.5

30.5

Bufo melanosticta

I

II

II

I

II

III

I

Kalophrynus interlineatus

I

Rana guentheri

II

II

II

II

II

II

I

Rana limnocharis

II

V

II

III

II

I

II

I

I

Table 3.10 Amphibian species recorded at transect 3

Species/date

15.6.00

22.6

23.7

29.7

11.8

23.8

3.9

12.9

15.11

29.11

6.4.01

10.4

29.4

5.5

8.5

21.5

30.5

Bufo melanosticta

I

III

I

Kalophrynus interlineatus

IV

Microhyla ornata

II

III

IV

Polypedates megacephalus

I

I

I

I

I

I

Rana guentheri

III

II

II

II

II

II

I

I

I

II

Rana limnocharis

I

III

II

II

II

I

Table 3.11 Amphibian species recorded at transect 4

Species/date

15.6.00

22.6

23.7

29.7

11.8

23.8

3.9

12.9

15.11

29.11

6.4.01

10.4

29.4

5.5

8.5

21.5

30.5

Bufo melanosticta

I

I

II

II

I

I

Kaloula pulchra

II

I

Polypedates megacephalus

I

I

I

I

Rana guentheri

II

II

II

IV

II

II

III

Rana limnocharis

II

II

I

II

I

II

Rana rugulosa

I

Table 3.12 Amphibian species recorded at transect 5

Species/date

15.6.00

22.6

23.7

29.7

11.8

23.8

3.9

12.9

15.11

29.11

6.4.01

10.4

29.4

5.5

8.5

21.5

30.5

Bufo melanosticta

II

I

I

II

Kalophrynus interlineatus

III

Microhyla ornata

II

III

III

Microhyla pulchra

III

III

Polypedates megacephalus

I

I

II

I

Rana guentheri

III

III

III

II

II

I

I

Rana limnocharis

II

II

III

II

II

II

Rana rugulosa

II

3.3.13 No additional species were encountered within the study area which were not also recorded from at least one of the transects.

Discussion

3.3.14 Nine species of amphibian were recorded at Long Valley between June and September. Precise numbers were frequently difficult to gauge due to several individuals (of different species) often calling at the same time. Also, females (which do not vocalise) were largely undetected, and only occasionally caught in the torchlight. For these reasons it is probable that the semi-quantitative assessments of numbers are conservative. Transect 5 had greatest amphibian diversity, with 8 species present. One species of conservation concern, Rana rugulosa (Fellowes et al., in prep.), was detected at transects 4 and 5 in May 2001. The eight other species present across the study area probably represent the five most common and widespread amphibians in Hong Kong (e.g. Karsen et al., 1998; Lau & Dudgeon, 1999).

Reptiles

3.3.15 Results for all five transects are summarised in Table 13 below.

Table 3.13

Reptile Species Recorded along Transects

Species/date

15.6.00

22.6

23.7

29.7

11.8

23.8

3.9

12.9

10.4.01

29.4

5.5

21.5

Calotes versicolor

1(T3)

Enhydris chinensis

1(T1) night

1(T2)

2(T2)

Eumeces chinensis

1(T1) 1(T4)

1(T1) 1(T2)

1(T3) 2(T4) 2(T5)

1(T2)

1(T5)

1(T1)

1(T5)

1(T1) 2(T2)

2(T2) 1(T3)1(T5)

Hemidactylus bowringii

1(T3)

1(T3) 1(T4)

2(T5)

1(T3)

1(T3)

1(T3)

Pytas mucosus

1(T5)

Ramphotyphlops braminus

1(T3)

1(T3)

3.3.16 Notable reptile sightings made outside of the transects (i.e. of species not otherwise recorded) included the following:

Chinemys reevesi - 1 individual at N133 on 15 August 2000. A common but possibly declining species locally (see Karsen et. al., 1998).

Trachemys scripta – 2 idividuals at N40 on 9 May 2001. A common, introduced species, thought to be displacing the native Chinemys reevesi in Hong Kong (Karsen et al., 1998).

Xenocrophis piscator – 1 individual at N56 on 9 May 2001. This species, while still quite common, is regarded as having declined somewhat in Hong Kong since the early 1980s as a direct consequence of wetland habitat loss (Karsen et al., 1998).

Discussion

3.3.17 Reptile sightings were scarce during the surveys, with only six common and widespread species encountered on the transects. Chinese Skink was the most commonly encountered species, recorded from all five transects.

Mammals

3.3.18 No evidence of mammals was encountered during the course of the transect surveys. However, a sighting of Small Asian Mongoose Herpestes javanicus was made at the northern end of Long Valley. This species appears to be spreading and becoming quite common in the lowlands of the northwest New Territories (Reels, 1996).

3.4 Conclusion

3.4.11 Survey findings to date have indicated that the Long Valley site supports mainly common and widespread species of dragonfly, butterfly, amphibian, reptile and mammal, typical of disturbed lowland habitats in Hong Kong. Two species of conservation concern – Reeve’s Terrapin Chinemys reevesi and Chinese Bullfrog Rana rugulosa - have been encountered.

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