Pak Phanang Estuary
Location:	8°21'-8°34'N, 99°58'-l00°l5'E; the mouth of the Pak Phanang River, Nakhon Si Thammarat Province, on the east coast of Peninsular Thailand.
Area:	Approximately 15,000 ha.
Altitude:	Sea level.
Biogeographical Province:	4.7.1.
Wetland type:	02, 05, 06, 07 & 09.
Description of site:	Extensive mudflats (3,910 ha) bordered on the seaward (eastern side) to the south of the Pak Phanang River mouth by a 15 km long sand spit. This spit still encloses an area of mangrove, estimated by Klankamsorn et al. (1981) at 7,420 ha. The spit is accreting rapidly, so that mangroves are gradually spreading westwards into the estuary. Much of the area is of low stature fringing mangrove or has been cut over, and only a few hundred hectares of tall, primary mangrove were detected during an aerial survey in October 1984 (Parish & Wells, 1985). To the north of the river mouth, the mangrove area, listed at 4,718 ha in Kiankamsorn et al. (1981), has been almost entirely cleared and replaced with shrimp ponds. The associated area of mudflats is estimated at 2,016 ha. A near-continuous line of human settlements extends along the seaward edge of the sand spit, scattered among coconut groves and Casuarina trees. There are also some areas of shrimp ponds. At the tip of the spit is an open sandy area, approximately 500m long at high tide, which may be an important roosting site for shorebirds. The entire area was inundated during a typhoon in 1962, when existing villages were destroyed with great loss of life and property. Since that time, the area has been repopulated. A large and seasonally variable amount of fresh water enters the system from the Phak Phanang River. Water depths range from 0.4-1.7m inshore to 2-6m in the outer bay. The tidal amplitude varies from 0.5m at neaps tides to l.3m at spring tides.
Climatic conditions:	Tropical monsoonal climate with an average annual rainfall of 2,500.9 mm; the wettest month is November (579.9 mm) and the driest, March (48.4 mm). The influence of the northeast monsoon is strong, and 43.5% of the annual rainfall usually takes place in November. The average annual temperature is 27.6°C (range 22.7-31.9°C). The relative humidity varies from only 73.0% in July to 85.0% in December.
Principal vegetation:	Mangroves, said to be species-rich, alternating with semi-natural wet grasslands. Coconut groves and Casuarina trees occur along the seaward edge of the spit; the Casuarina is regenerating naturally. On the western side of the river mouth, there are extensive areas of rice paddy.
Land tenure:	All intertidal areas and most or all of the areas of shrimp ponds and cleared mangrove are state owned. Human use of the site is, however, permitted and there has been much illegal occupation. Surrounding areas are mainly state owned, but similarly subject to much illegal occupation.
Conservation measures taken:	An area of 5,680 ha on the eastern side of the river mouth has been established as the Laem Thalemphuk Non-Hunting Area. This includes considerable areas of mangroves and mudflats as well as beach habitat along the sand spit. The mangrove area is classified as National Reserve Forest. Some artificial reefs and islands have been constructed offshore in order to enhance the fishery.
Conservation measures proposed:	Better protection of remaining mangrove habitat both inside and outside the Non-Hunting Area is needed. In addition, hunting should be strictly controlled; many migrant birds are hunted and netted illegally even within the Non-Hunting Area. The boundary of the Non-Hunting Area should be extended to encompass additional areas of mudflats, mangroves and fish-ponds.
Land use:	Fishing and aquaculture; agriculture in surrounding areas. Coconut plantations have been established along the sand spit; further inland, wet-season rice is planted. The nests of the Edible-nest Swiftlet Aerodramus fuciphagus are harvested from nearby buildings.
Possible changes in land use:	Increased clearance of mangroves for aquaculture. There is a proposal to build a harbour at the site in order to promote the development of a marine port. Continuing clearance of forest in the uplands in the water catchment area, remote from the site, may lead to further siltation.
Disturbances and threats:	Continued clearance of mangrove for the establishment of shrimp ponds and for charcoal production is a major threat to the site. Further clearance of mangroves for industrial development would be a threat if the harbour construction is permitted. The large-scale hunting and netting of birds is probably very damaging to their populations.
Economic and social values:	Considerable economic benefit is derived from the local fishing and aquaculture industries (penaeid shrimps and harvesting of the bloody cockle Anadara granosa). The harvesting of birds' nests is also very lucrative. Tourism is, however, as yet relatively undeveloped. The human population at the site depends for its very existence upon the maintenance of mangroves, which protect this vulnerable area from storm damage or potentially catastrophic inundation.
Fauna:	Information on the fishes is available from the National Institute of Coastal Aquaculture in Songkhla. Approximately 1,000 shorebirds were recorded during a partial aerial survey in October 1984, while 500 shorebirds of 13 species (including 106 Tringa totanus and 158 T. stagnatilis) were seen during a ground survey in December 1984 (Parish & Wells, 1985). Most of the area has never been effectively surveyed due to difficulties of access, and it is likely that much higher numbers actually occur. In particular, the site is known to have supported Limnodromus semipalmatus. Approximately 50 specimens were collected here between 1910 and 1926 (Robinson & Chasen, 1936), probably consisting mainly of birds taken on southward passage, and there is every reason to expect that the species still occurs. Several Leptoptilos javanicus are reportedly present; it is not known whether the species still nests. The sand beach on the eastern (seaward) edge of the spit can be expected to support nesting Charadrius peronhi and possibly also Sterna albifrons. Coastal vegetation along the sand spit is known to provide important shelter for many other birds during their southward migration, including Rallina fasciata, Pitta moluccensis and P. sordida. The site is a major feeding area for tens of thousands of Edible-nest Swiftlets Aerodramus fuciphagus, which nest in buildings nearby. The site is also the northernmost locality on the east coast for the Pied Triller Lalage nigra, which inhabits beach scrub and Casuarina trees. The mangroves are remarkable in that they support an isolated population of the Sambar Deer Cervus unicolor, a species usually associated with terrestrial habitats. The Long-tailed Macaque Macaca fascicularis and Fishing Cat Felis viverrina also occur in the area.
Special floral values:	The site probably supports the richest remaining mangrove flora of any east coast site.
Research and facilities:	A detailed survey of the marine and littoral environment has been carried out by the National Institute of Coastal Aquaculture, Songkhla. The temporary office of the Non-Hunting Area is located at Ban Kong Khong, some 15 km from the end of the sand spit. The area is a test site of the National Research Council's Remote Sensing and Mangroves Project, 1984-87.
References:	Jorgensen (1949); Klankamsorn et al. (1981); Parish & Wells (1985); Robinson & Chasen (1936).
Criteria for inclusion:	1b, 1e, 2a, 2b, 2c.
Source:	Jira Jintanugool and Philip D. Round.