Vertebrates

	The fish assemblages inhabiting shallow coral communities in Hong Kong’s eastern waters
	Amazing snake
	Turtles in Temples
	Nocturnal news - Latest on the hillside sightings at KFBG
	More on typhoons and birds

The fish assemblages inhabiting shallow coral communities in Hong Kong’s eastern waters

by Andy Cornish

Hong Kong has some of the northernmost coral communities along the coast of mainland China. These coral communities, which do not have a limestone base of accumulated hard coral as do true coral reefs, are most abundant as shallow, fringing communities in eastern waters. Surprisingly, given the economic importance of reef fishes in Hong Kong, little was known about the fishes inhabiting these coral communities, leaving me to start my Ph.D research virtually from scratch.

My first task was to compile a comprehensive list of all reef fishes known from Hong Kong, as those inhabiting coral communities would be a sub-set of these. A literature review of 34 publications dating back to 1846 produced 448 valid species from 63 reef fish families (those with some reef-associated species), I added a further 137 new species and 6 new families for Hong Kong from market and field collections over a 4 year period. Of the total 576 species (69 families), 75% are widely distributed in the tropical Indo-Pacific, 15% are temperate or sub-tropical Asian-Pacific species and 10% had other distributions. Hong Kong is, therefore, a region of overlap for tropical and temperate species along the coast of mainland China. This is to be expected as local sea-surface temperatures vary from 27 to 16 ^oC annually.

Fish assemblages were studied in detail on 3 coral communities at Sharp Island, Hoi Ha Wan Marine Park and Ping Chau (Mirs Bay). Diversity (per unit area), abundance and biomass were recorded using Underwater Visual Census (UVC) of permanent 2 0 x 3 m transects. Biomass can be calculated by estimating the lengths of each fish and inputting these values into species-specific length-weight relationships derived from caught fishes.

As fish assemblages differed little between sites or between the two years of the survey, 1997 and 1998, I will just deal with the overall results here. Some 195 species, or 34 % of the local reef fish fauna, were recorded from the 3 sites. These shallow, fringing coral communities, are clearly hotspots for reef fish diversity, despite their small size. The fish assemblages were dominated by very few species, with just 9 species, contributing > 90% to abundance and > 75% to biomass. Surprisingly, the species with the greatest mean biomass was the nocturnal Silver sweeper (Pempheris oualensis), a fish that had not even been recorded previously from Hong Kong. Large reef fishes were scarce at all 3 sites and the largest fish recorded in over 500 censuses was a 40 cm Great barracuda (Sphyraena barracuda), estimated to weigh 530 g. Overall, mean biomass in the shallows, where the corals are most developed, was estimated at 20-29 g.m^-2. This figure comprises 2 components, the "visually obvious" fauna which was sampled using UVC, and the cryptic fauna which was sampled on 2 random transects by surrounding the transects with fine nets and collecting all the fishes within.

The biomass estimate of between 20 and 30 g.m^-2 was highly revealing as it is amongst the lowest ever recorded from coral habitats in the Indo-Pacific, where biomass varies from 9.2 g.m^-2 for just 8 families on a heavily dynamited reef in Kenya (McClanahan & Kaunda-Arara 1996) to 237 g.m^-2 on the midshelf Great Barrier Reef (Williams & Hatcher 1983). The lack of larger reef fishes seems the fundamental reason for low biomass here, indeed most individuals of larger species recorded at the study sites had not reached size of sexual maturity. Biomass almost certainly used to be higher as more than 75% of long-time local divers responding to a questionnaire noted that parrotfishes (Scaridae) and groupers (Serranidae) had declined on coral communities in recent decades. Overfishing is the most likely cause of this decline, as these large reef fishes are slow to reach size of sexual maturation and respond poorly to being intensively fished, as they are in Hong Kong.

Fish assemblages varied seasonally, with diversity, abundance (excluding two common species, Chinese demoiselle [Neopomacentrus bankieri] and Broadbanded cardinalfish [Apogon fasciatus]), and biomass being greater in summer (July-September), than in winter (January-March). It appears that mobile fishes leave the coral communities and site-attached species spend more time within the coral framework in winter, apparently in response to cold water temperatures at this time. Wrasses, such as the common Bubblefin wrasse [Halichoeres nigrescens], may bury themselves under sand as is the case for some other wrasses, although this could not be proved.Similar seasonality in reef fish assemblages has also been reported from other high-latitude reefs in the Red Sea, Florida and Japan but is not a well-known phenomenon.

Chaetodon speculum "Mirror butterflyfish feed almost entirely on live coral polyps and are moderately abundant in Hong Kong"

At the moment, no coral communities in Hong Kong are protected from fishing although two coral areas, totalling 7.4 hectares, have been proposed as no-take areas in the proposed marine park at Tung Ping Chau. This is clearly an oversight if reef fish biodiversity is to be preserved in local waters. The scleractian corals themselves receive more protection than reef fishes, even though it is the latter that is seriously threatened by overexploitation. Even within the 2 marine parks, unlimited fishing with certain gears is still permitted by commercial license holders. Clearly, the duties of AFCD such as "protecting, restoring and, where necessary, enhancing marine life" are not being met, at least not with regard to reef fishes. Although no-take Artificial Reefs may protect some species, others only inhabit areas of hard coral, the coral-eating species of butterflyfish (Chaetodontidae) being a good example, or are quite mobile. The high proportion of sub-adult fish on coral communities also shows them to be nursery grounds for fish such as Blue-barred parrotfish (Scarus ghobban) and the most abundant local grouper, Chocolate hind (Cephalopholis boenak). This role as nursery grounds is surely enough reason to offer greater protection to coral communities in itself, given that very few local nursery areas have been identified to date (ERM HK Ltd. 1998). Conversely, the present low abundance of larger reef fishes means that fishers have little to lose financially by creating no-take zones of these nursery grounds. This is an important consideration as compensating fishers is currently a major obstacle to creating no-take reserves. Indeed, the issue of ex-gratia payments to fishers in compensation for creating the first no-take reserve at Cape d’Aguilar in 1996 has still not been resolved.

In the larger picture, coral communities are just one of the many habitat types that will need to be protected from exploitation if Hong Kong is serious about maintaining its substantial marine biodiversity. For example, The Great Barrier Reef Marine Park Authority has recently identified more than 70 marine "bioregions" in the Great Barrier Reef and is currently working to create no-take zones around representative areas of each (see www.gbrmpa.gov.au/ ). A comprehensive review of all habitat types is some way off in Hong Kong, but until then government could do much to protect the biodiversity and sustainability of reef fish stocks (and the corals themselves), by creating no-take areas encompassing our better coral communities.

Bibliography

Cornish A.S. (2000). Fish assemblages associated with shallow, fringing coral communities in sub-tropical Hong Kong: species composition, spatial and temporal patterns. Ph.D thesis, The University of Hong Kong, Hong Kong.

ERM HK Ltd. (1998). Fisheries Resources & Fishing Operations in Hong Kong Waters. Final Report submitted to AFD, March 1998.

McClanahan T.R. & Kaunda-Arara B. (1996). Fishery recovery in a coral-reef marine park and its effect on the adjacent fishery. Conservation Biology 10(4): 1187-1199.

Williams D.McB. & Hatcher A.I. (1983). Structure of fish communities on outer slopes of inshore, mid-shelf and outer shelf reefs of the Great Barrier Reef. Marine Ecology Progress Series 10(3): 239-50.

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Amazing snake

by Jonathan Kolby & James Lazell

The Conservation Agency

Herpetologists continue to discover species of reptiles that are new to Hong Kong despite decades of collecting effort going back to the great naturalists Dr. Geoffrey Herklotts and John Romer. Far more rarely, a species new to science appears, as in 1987 when Fr. Anthony Bogadek discovered the borrowing lizard that bears his name: Dibamus bogadeki. The notion that a new reptilian genus might be discovered in Hong Kong seems scarcely credible.

On 4 July 1999 one of us (JK) caught a small, yellowish to olive-drab snake swimming in the central gutter of the Keung Shan catchwater on Lantau, where the catchwater crosses the main Tai O road above Lower Keung Shan village. In colour, virtual lack of pattern, and head shape, this snake is quite unlike any species known from Hong Kong. Most amazing, however, is the presence of three prefrontals, a condition not seen in any genus known from Guangdong or adjacent Provinces: Figure 1.

The specimen keys out to Opisthotrophis andersonii if one chooses the character one prefrontal, or to "Rhabdophis" if one chooses two. With three, and its other peculiarities, it looks like none of these. The snake is a hatchling or newborn with a yolk sac scar. It is 150 mm snout-to-vent, with a tail length 61 mm. There are 19 dorsal rows at the neck, 19 at midbody, and 17 at the vent. There are 124 ventral plates and 82 paired subcaudals. The anal plate is divided in line and the dorsal scales are heavily keeled with the exception of rows 1-2. Internally, the specimen has prominent vertebral hypapophyses with two tendinous muscle attachments on all body vertebrae, the defining feature of the subfamily Natricinae of family Colubridae, to which Opisthotrophis and Natrix sensu lato ("Rhabdophis," "Amphiesma," etc.) belong.

We are indebted to Drs. Michael Lau (Kadoorie Farm & Botanic Garden), Jacques Gauthier and Theodora Pinou (YalePeabody Museum) and Van Wallach (Museum of Comparative Zoology) for the examination of the specimen. Karsten Hartel (Harvard) prepared x-rays and William Sacco (Yale) made the photographs from which Figure 1 was traced.

So far, the view that this snake represents a new, unnamed, and undescribed genus seems inescapable. We will invest considerable effort in searching for more specimens.

"Our over-riding goal is to preserve the diversity of life. Our guiding principle is that conservation is the application of the science of ecology, a complex and often arcane composite of the biological and physical sciences." James D. Lazell, Ph.D., President (from the Conservation Agency website)

P.9-10

Turtles in Temples

by Cheung Sze Man

Temple ponds or ‘fang sheng chi’ (ponds for keeping animals alive) have more than 15 years of history in Hong Kong. Turtles are frequently released into temple ponds for religious and cultural purposes. Similar practices have also been recorded in Taiwan (Chen et al., 2000) and Nepal (Shrestha, 1997). Ironically, these ponds, that are intended to keep turtles alive, have put chelonian conservationists in a dilemma.

The turtle pond in Wong Tai Sin Temple (Wong Tai Sin) was visited at least once every three months from 1995 onwards. Temple ponds in Yuen Yuen Hok Yuen (Tsuen Wan) and Wan Tsuen Sin Koon (Fanling) were also checked at least once a year during the same period and the species observed were recorded (Table 1). At least 10 species have been recorded so far and all except Trachemys scripta elegans were Asian species. The most frequent and abundant species was T. s. elegans while Chinemys reevesii followed. In recent years, more and more Cuora amboinensis and Cuora galbinifrons were observed in temple ponds, probably due to their ready availability from the local food market. Except for T. s. elegans, all species are of important conservation value. All Cuora species and Indotestudo elongata are listed on CITES Appendix II. Moreover both Cuora galbinifrons and Cuora trifasciata are critically endangered and most other recorded turtles are endangered (IUCN, 2000).

In fact, for many Asian turtle species temple ponds can be short-term sanctuaries from the regional food market. Also, releasing turtles into temple ponds by religious organizations causes less catastrophic ecological impact when compared to exotic turtles being released to the wild. However, as noted by Chen et al. (2000), ‘temple ponds are unsuitable for turtles’. In Hong Kong, terrestrial I. Elongata individuals were once observed submerged in water (water level was half the shell depth) with T. s. elegans. A temple worker told the author that the diet of those omnivorous/carnivorous turtles consisted of leftover vegetables and rice only. The hygiene in turtle ponds is also worrying. As conservation organizations are usually short of funds, ‘buying’ turtles from temples for conservation management is impractical. Instead, temples should be invited to donate the endangered species for a captive breeding programme. However, as the turtles are the property of the temples, the willingness to co-operate still depends on the religious organizations. In Taiwan, a temple is planning an ecological garden for displaying native turtles to help in conservation education (Chen et al. 2000). Communication with the local religious organizations would be an appropriate measure to urge the temples to improve the husbandry of the turtles in those ponds. Education of the Buddhists and Taoists could also make them understand the right way to conserve turtles and to change their perception of turtles from blessing tools to lives that they should respect. In the current Asian turtle survival crisis, the status and role of temple turtle ponds are worth considering.

Bibliography

Chen, T.-H., Lin, H.-C., and Chang, H.-C. 2000. Current status and utilization of chelonians in Taiwan. In: van Dijk, P.P., Stuart, B.L. and Rhodin, A.G.J. (Eds.) Proceedings of a Workshop on Conservation and Trade of Freshwater Turtles and Tortoises in Asia. Pp.45-51.

IUCN. 2000. 2000 IUCN Red List of Threatened Species (cited from World Conservation Monitoring Centre. http://www.wcmc.org.uk/CITES/common/dbase/fauna/index.html. ‘CITES Listed Species Database---Fauna’).

Shrestha, T.K. 1997. Status, biology, conservation, and management of tortoises and turtles in the Himalayan foothills of Nepal. In: Abbema, J.V. and Pritchard, P.C.H. (Eds.) Proceedings: Conservation, Restoration, and Management of Tortoise and Turtles---An International Conference. Pp.278-286.

Table 1. Chelonian species recorded from temple ponds in Hong Kong since the mid-1990s. WTS=Wong Tai Sin Temple (Wong Tai Sin), WTSK=Wan Tsuen Sin Koon (Fanling), YYHY=Yuen Yuen Hok Yuen (Tsuen Wan).

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Nocturnal news - Latest on the hillside sightings at KFBG

by Gary W J Ades

Executive Director (Acting)

In previous issues of Porcupine! I, and other members of staff have provided anecdotal animal sightings made within the 148 hectare protected area on the hillside at KFBG. Sightings of some mammals are becoming more frequent and in particular our security guards, having been equipped with a camera for their night time patrols, are taking amazing pictures of the nocturnal wildlife on our hillside. These photos, combined with occasional placement of infra-red cameras in ‘mammal-active’ areas, have provided the fauna conservation department with probably the best available information on nocturnal wild animal activity for any single site in Hong Kong. The information for the mammals is not very scientific in as much as we have not undertaken any systematic marking/tagging research, however, the sightings captured on film alone are quite incredible.

The guards have, on several occasions, caught on film a snake which had not until recently been photographed in the wild in Hong Kong, and have clear evidence to suggest, at least on our hillside, that all deer records are Muntiacus muntjak (not reevesi). Barking Deer, Wild Boar and Porcupines literally pose for their pictures. Apparently these creatures, which have highly acute olfactory senses, see the guards as little threat and, having got used to the characteristic sound of the patrol vehicle, they get on with their nocturnal habits as normal and in many cases seem not too perturbed by the odd camera flash.

We have a set of monthly photo records of hillside fauna going back 2 years. This information will be valuable in helping us determine ‘hot spots’ for mammal activity. It is already clear that mammals such as the Barking Deer have favoured areas. Also,Wild Boar activity, although random at times, will no doubt be shown to correlate with the presence of certain seasonal crops and tubers on and around our organic terraces.

Clearly, the two civet species, Pangolin and Ferret Badgers, all recorded on our hillside on several occasions, are less willing to hang around long enough to be photographed by the guards. Both civet species have been recorded by our infra-red cameras and in August 2000, I was able to approach a juvenile Masked Palm Civet, apparently playing on a road side vine. With the animal outlined by the light beam of the jeep I was driving, I was able to leave the vehicle and approach to within 1 metre before it ran up the vine with great agility and disappeared into the canopy of an adjacent tree.

Pangolins are rarely seen. Both sightings in the last 5 years have occurred on the upper hill roadside; one was due to disturbance by feral dogs. Pangolins are obviously not so willing to use man-made roads to transit to different areas. Ferret Badgers are extremely shy and are able to detect human approach with their extremely good sense of smell. Anybody who has seen a Ferret Badger or Pangolin foraging will have immediately noted their poor visual acuity. Both species plod along like ‘vacuum cleaners’ with long snouts to the ground apparently moving randomly until a scent is picked up, both appear to have fairly good hearing which may also contribute to guide them through the clutter of the night. ’Guide’ might not be the best word since both animals will often collide with fairly large objects as they snuffle along!

Clearly, the two civet species, Pangolin and Ferret Badgers, all recorded on our hillside on several occasions, are less willing to hang around long enough to be photographed by the guards. Both civet species have been recorded by our infra-red cameras and in August 2000, I was able to approach a juvenile Masked Palm Civet, apparently playing on a road side vine. With the animal outlined by the light beam of the jeep I was driving, I was able to leave the vehicle and approach to within 1 metre before it ran up the vine with great agility and disappeared into the canopy of an adjacent tree. Pangolins are rarely seen. Both sightings in the last 5 years have occurred on the upper hill roadside; one was due to disturbance by feral dogs. Pangolins are obviously not so willing to use man-made roads to transit to different areas. Ferret Badgers are extremely shy and are able to detect human approach with their extremely good sense of smell. Anybody who has seen a Ferret Badger or Pangolin foraging will have immediately noted their poor visual acuity. Both species plod along like ‘vacuum cleaners’ with long snouts to the ground apparently moving randomly until a scent is picked up, both appear to have fairly good hearing which may also contribute to guide them through the clutter of the night. ’Guide’ might not be the best word since both animals will often collide with fairly large objects as they snuffle along!

One interesting fact gained from infra red photography is that the home ranges of both Civet species overlap on our hillside, and that Barking Deer and Masked Palm Civets will tolerate each other at the same foraging site. Also, considering their abundance, Wild Boar are extremely difficult to capture using the infra-red set up, possibly due to their acute sense of smell, picking up human scent on the equipment.

	Wild Boar and Porcupine are major wanderers with identified family groups (identified by age and number of young) being seen on the upper and lower hillside within the same period.

A kitten Leopard Cat was discovered dead behind our administration building in September this year, indicating the presence of a breeding population nearby. These animals may account for the many reflected eyes we see on night time mammal treks but which do not stay around to be identified! My previous encounters with Leopard Cats in HK have been the result of catching their ‘cats eyes’ in torchlight, often quite close to man-made paths and buildings. We even have one feral cat on our hillside that has suspiciously leopard cat-like markings, a very attractive animal, also caught on film by our guards.

We are able to incorporate these wild sightings in our educational information, so that visitors can be kept up to date on the latest nocturnal sightings and to raise awareness of the existence of these animals in protected areas in Hong Kong. Under our hillside ecological management programme we will be paying close attention to the seasonal records of mammal sightings, which will help us to determine any management measures that would help to protect and perhaps enhance conditions for some species and also consider arrangements to minimise damage to crops and flowers on our hillside terraces. This information will be an important part of our integrated management plans, since there will always be conflict between human needs and those of wild animals. With the known diversity of wildlife within our protected area, and the existence of our agricultural activities on the fringes of natural woodland, we have a great and important opportunity to monitor animal activities and needs and relate these to the human activities.

A list of the nocturnal life which has been seen between 1998 and 2000, follows. All except the Ferret Badger, Scops Owl and Nightjar have been photographed in the wild. Also, the approximate frequency of sightings is indicated. Please note that many sightings may be the same animals, we would have to mark the animals in some way if we wished to be more certain about the identity of individuals. In future and with AFCD sanction, we could perhaps consider colour-marking Barking Deer, Porcupines and Wild Boar so that they could be identified for a few weeks (perhaps a blowpipe loaded with a non-toxic paint ball could be employed to do this?).

C - Common (recorded nearly every month)

O - Occasional (< 5 sightings/year)

R - Rare (rarely seen)

(this reference does not necessarily represent status - Ferret badgers although rarely seen are thought to be fairly abundant on our hillside)

* infra-red camera success

NB this is not a checklist of the fauna records for our hillside, merely those animals recorded during night time patrols and captured on film.

P.11-12

More on typhoons and birds

Richard T. Corlett

In Porcupine! 20, Michael Leven and Amanda Haig describe the effects of Typhoon York (September 16th, 1999) on Hong Kong's birds. Although this was the biggest typhoon for 16 years, the impact on birds was apparently minor, in part because September is well past the main breeding season. In 1971, in contrast, Typhoon Freda struck on June 18th, right in the middle of the breeding season. An article by Elizabeth Hechtel in the AFD's newsletter Wildlife Conservation (No.13), describes the damage to the Sha Tau Kok egretry (presumably at Yim Tso Ha):

Innumerable nests were destroyed and the game wardens there reported picking up as many as 300 young dead birds for burial. Adult birds also suffered, especially the Chinese Pond Herons–. Bodies were still to be found lying on the ground, but two birds not yet dead we removed with a faint hope of restoring them to health.

The Hong Kong Bird Report for the year mentions that the egretry in Yuen Long suffered similar damage.

Bibliography

Hechtel, E. (1971). Typhoon Freda at Sha Tau Kok and the nursing of some bird casualties. Wildlife Conservation 13:12.

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