Ao Phang-Nga (Phang-nga Bay)
Location:	8°08'-8°26'N, 98°27'-98°45'E; in the Province of Phang-nga, on the west coast of Peninsular Thailand; enclosed to the west by the island of Phuket.
Area:	c.65,000 ha.
Altitude:	Sea level; hills around the margins of the site rise to 439m.
Biogeographical Province:	4.5.1.
Wetland type:	01, 02, 03, 04, 05, 06 & 07.
Description of site:	A huge shallow bay fringed with extensive mangrove swamps, extending north from Phuket Island eastwards along the mainland coast past the mouths of six river systems to the mouth of the Mae Nam Marui. The easternmost boundary of the site is delimited by the large promontory of Khao Ao Muang, which separates the site from another major mangrove inlet, Ao Luk (Krabi Province). A great many limestone pillars and islands rise sheer from the coastal flats, and there are extensive shallows offshore, only 1 -4m deep at mean low water. The site encompasses the two offshore islands of Ko Yao Yai and Ko Yao Noi together with a great many smaller islets. Klankamsorn et al. (1981) give the area of mangrove as 21,181 ha and that of intertidal mudflats as 4,048 ha (in 1979). There is massive freshwater run-off from forested hills around the bay during the southwest monsoon. Salinities of 31.5 p.p.t. (April) and 33.0 p.p.t. (August and January) have been recorded. The tidal amplitude at Ao Nang, Krabi, varies from l.Om at neap tides to 3.Om at spring tides. The tidal regime is complex; the usual pattern is two high tides per day, but there are many irregularities.
Climatic conditions:	Tropical monsoonal climate with an average annual rainfall of 2,379.3 mm, most of which falls during the southwest monsoon, from May to October. The relative humidity varies from 68% in February to 81% in October. The average daily temperature is 28.1°C (range 24.0-31.3°C). (Data from Phuket Sarigabutrt et al.,1982).
Principal vegetation:	Extensive mangrove forest. Most of the area has been logged and is dominated by large stands of Rhizophora and other species in relatively uniform age classes. There are very few areas which still support larger mangrove trees. The structure and composition of the mangrove forest has been studied by Aksornkoae and Kongsangchai (1980). The principal vegetation in adjacent areas is semi-evergreen rain forest, with drier sub-types on exposed limestone outcrops. Rubber plantations dominate in lowland areas outside the National Park.
Land tenure:	The wetland is state owned and open to public use in many areas; surrounding areas are both privately owned and state owned.
Conservation measures taken:	The Ao Phang-nga National Park, established in 1981, covers an area of 40,000 ha. Most of the park consists of open water, rocky headlands and forested mountains, and only a relatively small proportion of the total mangrove area is included within the park boundaries. Most of the remaining mangroves have been designated as National Reserve Forest, parts of which are logged under concession.
Conservation measures proposed:	Phang-nga Bay is a designated site of the ASEAN/USAID Coastal Resources Management Project (CRMP). Environmental consultants attached to this project may be expected to produce recommendations for its conservation and integrated development. Increased areas of mangrove should be incorporated within the Ao Phang-nga National Park. Walkways should be constructed in order to introduce visitors to the mangrove ecosystem. A comprehensive survey of the wildlife resources of Phang-nga Bay is required, as the area has never been adequately studied. Better protection of both marine and coastal resources is needed as most of the area is subject to the depredations of boatmen and fishermen who continue, for example, to collect the eggs of nesting terns and other birds for food.
Land use:	Fishing, the cutting of mangroves for timber, and harvesting the fronds of Nypa palm for the production of thatch. The area is a major tourist attraction and a great many boatmen realize income from parties of sightseers. Caves support populations of Edible-nest Swiftlets Aerodramus fuciphagus, the nests of which are harvested and sold as a luxury foodstuff. Phang-nga Bay is one of the principal sites considered for aquaculture development under the FAO Bay of Bengal Programme. The development of fin-fish cage culture, cockle culture and mussel/oyster culture has been promoted. Up to the end of 1985, there were 880 fish cages divided amongst 262 owners in ten villages in Phang-nga Province (Drewes, 1986). In some parts of the area, tin is extracted from sediments obtained by dredging. Rubber is widely cultivated in surrounding areas.
Possible changes in land use:	The volume of tourism seems destined to increase greatly. Land use and development of the area is being examined under the ASEAN/USAID Coastal Resources Management Project (CRMP), and various recommendations for the zoning of land use are likely to be made. The Small Scale Fisheries Development Project of the Department of Fisheries may promote aquaculture in some parts of the site. Artificial reefs have been constructed in some areas.
Disturbances and threats:	The continued cutting of mangroves, both legally and illegally, threatens the integrity of the site, and conversion for aquaculture puts further pressure on the mangroves in the more sheltered areas. Tin dredging may threaten both the mangrove ecosystem and marine ecosystem by siltation. Many areas of corals have already been damaged. Fishermen continue to take the eggs and young of sea-birds such as terns for food. In addition, marine animals such as dugongs and sea-turtles are occasionally caught in trawl nets.
Economic and social values:	Economic and social values: The area has immense value as a source of mangrove products and for its fishery. Cage culture for fin-fish, developed under the FAO Bay of Bengal Programme, has proved to be very lucrative, yielding an estimated profit of Bht.l,444 per cage per year. Cockle culture is much less successful, attracting only businessmen and large entrepreneurs, since it depends for its success upon the illegal import of "seed"from elsewhere; small-scale fisherfolk benefit only as labourers (Drewes, 1986). Phang-nga Bay is of great importance for research, and is being studied by biologists from the Phuket Marine Biological Center. In addition, the site is a valuable national and international recreational heritage on account of its outstanding beauty.
Fauna:	Fauna: The area has never received a complete survey. However, it almost certainly continues to support the scarce and possibly threatened Ardea sumatrana, and may also support Heliopais personata. Egretta sacra and Butorides striatus are very common, and Pelargopsis amauroptera and Pitta megarhyncha probably occur. The islets support breeding colonies of the terns Sterna dougallii, S. sumatrana, S. bergii and probably S. anaethetus; the sand beaches provide nesting sites for Charadrius peronii and Sterna albifrons. S. bengalensis has been recorded from the island of Ko Yao Yai, but its status is unknown (Nadee, 1982). There is a relatively high density of both Haliastur indus and Haliaeetus leucogaster in the area. Wreathed Hornbills Rhyticeros undulatus are still fairly common. Macaca fascicularis occurs in the area, and the bay may still support a few Dugongs Dugong dugong (Dobias, 1982).
Special floral values:	The area supports one of the most extensive areas of mangrove remaining in Thailand.
Research and facilities:	Accommodation is available at the headquarters of Ao Phang-nga National Park, at Ban Chap Phrae. Aksornkoae and Kongsangchai (1980) have studied the structure and floristic composition of the mangroves; Papavasith and Setti (1982) have carried out a study of mangrove benthos, and an ongoing programme of research, funded by the Department of Fisheries, is being undertaken from Phuket Marine Biological Center. A management plan for the site is being developed under the ASEAN/USAID Coastal Resources Management Project.
References:	Aksornkoae & Kongsangchai (1980); Dobias (1982); Drewes (1986); Klankamsorn et al. (1981); Nadee (1982); Papavasith & Setti (1982); Parish & Wells (1985); Sarigabutr et al. (1982); Whitmore (1975).
Criteria for inclusion:	1b, 1e, 2b.
Source:	Jira Jintanugool and Philip D. Round.