Ko Libong Non-Hunting Area and Hat Chao Mai National Park
Location:	7°12'-7°22'N, 99°20'-99°29'E; the mainland coast and a large island (Ko Libong) 3.5 km offshore, Trang Province, Peninsular Thailand.
Area:	Ko Libong is approximately 3,400 ha; Hat Chao Mai National Park is 23,100 ha, but most of this area is open sea.
Altitude:	Sea level. Forested hills on Ko Libong and Hat Chao Mai rise to 311m and 432m respectively.
Biogeographical Province:	4.7.1.
Wetland type:	01, 03, 04, 05, 06 & 07.
Description of site:	The site lies to the west of the mouth of the Mae Nam Trang. The eastern two-thirds of Ko Libong are mainly low-lying mangroves fringed by mudflats to the south and sand flats to the north. The western end is steeply mountainous and still supports some terrestrial forest. The intertidal zone is narrow and rocky; a long sand beach extends along the western shore and there are some offshore coral reefs. A small island (Ko Hard Toop), a ridge of sand and mud with small areas of mangrove, lies 500m off the southeast tip of Ko Libong and is an important roosting site for shorebirds. The boundary of the Non-Hunting Area encompasses the whole of Ko Libong together with some areas of mainland coast including considerable areas of mangrove. There are three main villages on the island. Hat Chao Mai National Park encompasses a stretch of the mainland coast together with two offshore islets. It is best treated together with Ko Libong as the two are adjacent and can be regarded as a single wetland site. The park comprises sand beaches backing onto dry coastal scrub, plantations and steep, forested crags. The most extensive areas of mangrove, however, lie outside the boundaries of the park. The system receives fresh water from the Mae Nam Trang, to the east of the site, and as run-off from the nearby forested crags through numerous small creeks in the mangroves. There are extensive shallows of 1-3m in depth to the southeast of Ko Libong. The strait separating the island from the mainland is 5-7m deep. The salinity is high, approaching fully marine conditions. At low tide, approximately 1,000 ha of sand flats and mudflats are exposed around the island, and approximately 700 ha are exposed along the mainland coast. Except for one sand bar, to the east of the mouth of Khlong Chao Mai off Hat Chao Mai, the mainland mudflats are covered by normal high tides. This is an important alternative roosting area for shorebirds when Ko Hard Toop is covered, as during high spring tides. The tidal amplitude is approximately two metres.
Climatic conditions:	Tropical monsoonal climate with an average annual rainfall of 2,379.9 mm; the region receives rain from both monsoons, the southwest from May to October and the northeast into December. The relative humidity ranges from 70% in February to 86% in October. The average daily temperature ranges from 26.4°C in November to 29.0°C in April. The prevailing winds are west from May to October, and northeast or east in other months. (Data taken at Trang; Sarigabutr et al., 1982).
Principal vegetation:	Mangrove forest dominated in most areas by young Avicennia alba; mature A. alba occurs along the seaward fringe, and mature Sonneratia alba and Rhizophora mucronata occur within the influence of the channels. The inner mangrove zone is co-dominated by R. mucronata and R. apiculata. The mangrove is accreting in only a few places along the mainland coast and southern shore of Ko Libong. Much of the area has been logged over, though some large trees remain, particularly around the Non-Hunting Area headquarters. Some dry grassy clearings occur on patches of sandy soils within the mangrove. Four species of sea-grasses have been collected from the mudflats, but these have not as yet been identified. The vegetation in adjacent areas includes beach scrub dominated by Casuarina equisetifolia, rubber plantations, some of which contain much secondary growth, and other cultivation, especially coconut palms and bananas, around villages on the mainland.
Land tenure:	Areas of mangrove are state owned and leased out to concessionaires.
Conservation measures taken:	The entire island of Ko Libong and part of the mainland coast are incorporated within the Ko Libong Non-Hunting Area. The mainland coast to the west of the Khlong Chao Mai is incorporated within the Hat Chao Mai National Park. Areas of mangrove are, however, excluded from the park.
Conservation measures proposed:	Swennen et al. (1986) suggest that human use of the mudflat areas around the small island of Ko Hard Toop should be reviewed and, if necessary, reduced, since disturbance levels are very high. Better enforcement of existing wildlife protection legislation is needed. The boundaries of Hat Chao Mai National Park should be extended to encompass some areas of mangrove. The status of Ephippiorhynchus asiaticus should be determined and any nesting and roosting areas protected.
Land use:	Inshore fishing, using hand nets and trawl-nets, and harvesting of mudflat invertebrates for food. The latter include bivalve molluscs, sea cucumbers, anemones, priapulids and crabs. There is a small charcoal-producing industry on the northeast shore of Ko Libong, where Rhizophora spp are harvested on rotation. Hunting of birds and the few larger mammals occasionally takes place. Cultivation of rubber, bananas, coconut palms and rice in surrounding areas.
Possible changes in land use:	There may be an increase in logging of remaining mangrove in the future. The use of the area for tourism is certain to increase.
Disturbances and threats:	Shorebirds are hunted and netted on a small scale within Ko Libong Non-Hunting Area, and there is a considerable amount of indirect disturbance to roosting and feeding birds. In addition, monitor lizards Varanus sp are caught in noose traps and eaten by villagers. Possible future damage to or removal of larger mangrove trees may pose a threat. Over-exploitation of benthic invertebrates may threaten natural stocks. Slash-and-burn agriculture continues to denude hills both in the immediate vicinity of the site and in the headwaters of the Trang river. This could lead to increased siltation at the site.
Economic and social values:	Both the inshore and offshore fisheries are important on a local scale. The site already has some importance for small-scale tourism; boats are sometimes rented from villagers by bird-watchers or general tourists. The site has considerable importance as a possible future research or bird migration monitoring station, and is one of the most frequently visited shorebird sites in the Peninsula.
Fauna:	Ko Libong is one of the most important staging and wintering areas for shorebirds in the country; it is used by more than 10,000 shorebirds of up to 33 species each season. Peak counts for the commoner species include over 2,000 sandplovers Charadrius mongolus and C. leschenaultii and: 600 Numenius phaeopus 200 N. arquata 1,180 Limosa lapponica 410 Tringa totanus 300 Xenus cinereus 350 Calidris tenuirostris The concentration of L. lapponica is the largest such recorded in Thailand and the Malay Peninsula combined. Scarcer species include Limnodromus semipalmatus (75 in October 1984), Tringa guttifer (groups of up to 11 birds recorded every winter since 1982), and Dromas ardeola (3-12 birds recorded each winter). This is one of the few known wintering Sites for T. guttifer in the world, and the only regular wintering area for D. ardeola in Southeast Asia. Other waterfowl of note include Egretta sacra (maximum 50 birds), Charadrius peronhi (breeds at Hat Chao Mai), Sterna bergii (maximum 100 birds, presumed to breed locally), Sterna bengalensis (non-breeding visitor, maximum 60 birds), and Heliopais personata (one recorded in March 1986). A few pairs of Sterna anaethetus, S. dougalli and S. sumatrana breed in the area. There is one unconfirmed but probably reliable sighting of the endangered Sterna bernsteini; 10 were reported in July 1980 (P. Poonswad, pers. comm). Unconfirmed reports of Egretta eulophotes have also been received. Hat Chao Mai is the only known nesting site in the Malay Peninsula for Ephippiorhynchus asiaticus (Robinson & Chasen, 1936), and the species is believed still to occur (B. Amget, pers. comm.). The scarce and local Pelargopsis amauroptera and Pita megarhyncha both occur in the mangroves on Ko Libong. In all, at least 126 species of birds have been recorded in the area. Monitor lizards Varanus sp are present on the island, and dolphins have been seen offshore.
Special floral values:	The site contains well developed stands of mature mangrove forest which are amongst the best and least disturbed examples of this habitat type on the entire west coast of Thailand.
Research and facilities:	Count data on shorebirds are available from the Interwader Project at the Asian Wetland Bureau in Kuala Lumpur and from the Center for Wildlife Research at Mahidol University in Bangkok. The Interwader Project has conducted some sampling of benthic invertebrates, but the results are not yet published. Accommodation is available at the headquarters of Ko Libong Non-Hunting Area, at the extreme eastern tip of the island, and at Hat Chao Mai National Park.
References:	Bijlsma & de Roder (1985); Eve & Guigue (1982); Parish & Wells (1985); Robinson & Chasen (1936); Sarigabutr et al. (1982); Swennen et al. (1986).
Criteria for inclusion:	1b, 2a, 2b, 2c, 3b.
Source:	Jira Jintanugool, Philip D. Round and interwader.