Khao Sam Rol Yot National Park
l2°07'-12°16'N, 99°52'-100°0l'E; 20 km south of the town of Pranburi, in Kui Bun District, Prachuap Khiri Khan Province.
Total area 13,000 ha of which approximately half is wetland habitat.
Sea level.
Biogeographical Province:
Wetland type:
03, 04, 05, 06, 07, 08, 10, 11, 15 & 19.
Description of site:
An area of coastal marshes, paddies and patches of degraded mangrove situated at the foot of an outcrop of limestone mountains which rise to 605m. The site encompasses what appears to be the largest freshwater marsh in Thailand, totalling almost 6,000 ha, together with 640 ha of open coastal flats and 950 ha of paddies. Between the mouths of the Khlong Khao Daeng and the Khlong Bang Pu, sandy beaches alternate with small areas of mudflats, shrimp ponds and rocky cliffs. There are five offshore islets along this stretch. Apart from a few hectares north of the mouth of the Khlong Khao Daeng, most of the mangrove occurs in narrow fringes along the niverine margins. There is a high human population density in the area and the site has been greatly modified by man, with drainage ditches and embankments being constructed in order to control water levels around the margins of the marsh. The freshwater marsh is about 1-2m deep, and is fed by springs, as well as by two rivers. There is considerable seasonal variation in the extent of flooding, but the marsh has never dried out. Parts of the area are tidal. The tidal amplitude at Hua Hin, some 40 km to the north, varies from 0.9m at neap tides to 2.7m at spring tides.
Climatic conditions:
Tropical monsoonal climate with an average rainfall of 1,036 mm, 7 1.3% of which falls during the southwest monsoon, from May to October. The mean annual temperature is 27.4°C (range 13.9-38.6°C).
Principal vegetation:
The main freshwater marsh is dominated by Phragmizes australis, which covers an area probably in excess of 3,000 ha. Around the margins are small areas of Typha angustifolia, low Scirpus, probably S. articulatus, Eleocharis spp, Cyperus spp. Arundo donax and Themeda arundinacea. The drier margins of the site support clumps of Bambusa sp. Rhizophora is dominant in the mangrove stands along the tidal reaches of the rivers. Casuanina equisetifolia is found along sandy coastal beaches and sand spits. Mixed deciduous woodland and bamboo cover the dry, rocky mountains adjacent to the site. Rice is grown in wetter areas, with some dryland crops scattered among clumps of bamboo on dry sandy soils.
Land tenure:
The wetland is state owned and open to public. Illegal encroachment has occurred in many parts of the marsh. The nearby rocky mountains are state owned, with adjacent lowlands being farmed as private small-holdings.
Conservation measures taken:
Most of the area is protected as a National Park. Some planting of Rhizophora mangroves has been undertaken, and a preliminary management plan for the site has been prepared (Pirawat, 1986).
Conservation measures proposed:
It is proposed that human use of the area be zoned (Pirawat, 1986). The boundaries of the park should be properly surveyed and extended to include the entire freshwater marsh area as well as at least some of the areas which are under aquaculture. Better protection of both freshwater and coastal habitats is needed. Efforts to suppress illegal hunting of wildlife should be increased. It may be desirable to limit access by tourists to sandy beaches at certain times of the year in order to avoid disturbance of nesting Charadnius peronii.
Land use:
Fishing, chiefly with the aid traps; also aquaculture in brackish areas, rice cultivation and cattle grazing. Rice cultivation (one crop of wet-season rice per year), cultivation of pineapples, vegetables and sugar cane, and cattle grazing in adjacent areas.
Possible changes in land use:
Intensification of aquaculture in brackish water areas and a slow increase in tourism.
Disturbances and threats: The principal threats stem from intensified use by local people of habitats within, or immediately adjacent to, the park, a problem which is exacerbated by the fact that the park's boundary has not yet been formalized. Many people have land rights within the park, and in recent years, many areas have been greatly modified by aquaculture. There is a danger that such activities, through modifying the tidal flow patterns, could change the present beach topography. There is small-scale agricultural encroachment into the drier margins of the freshwater marsh. Local people hunt wildlife illegally both in the marshy areas and in the adjacent forested mountains within the park. Increased human use of sandy beaches, especially through tourism, could disturb sensitive nesting species such as Charadrius peronii and Sterna albifrons. The use of snares to catch waterbirds, particularly rails and crakes, for human consumption appears to be increasing.
Economic and social values: The area is clearly of great local economic importance for both its freshwater and brackish water fisheries, while the village of Ban Khao Daeng is also a small marine fishery port. Tourism is of growing importance; visitors to the National Park often purchase provisions locally, and boatmen are often hired to take visitors out to accommodation on remote headlands, inaccessible by land. The site has great recreational value because it offers the visitor a very wide variety of natural attractions (sandy beaches, clear waters offshore, islands, caves, mountains, woodlands and wetlands) within a relatively small area.
Fauna: A total of 237 species of birds (both landbirds and waterbirds) has so far been recorded at the park. The park is of importance for many larger waterbirds; it is one of very few sites in Thailand where Ardea purpurea breeds, and there is a small egret colony. Dendrocygna javanica is present all year round as are Rallus striatus, Porzana cinerea and Porphyrio porphyrio. Other breeding species of conservation importance include Haliaeetus leucogaster (one or two pairs), probably Falco peregrinus, Sterna albifrons, Charadrius peronii (about five pairs), and, on offshore islets, S. sumatrana and probably S. bergii.

Annual wintering or non-breeding visitors include Ardea cinerea (over 60 birds), Mycteria leucocephala (1-5 birds), Leptoptilos dubius (usually one individual) and Threskiornis melanocephalus. A few thousand Dendrocygna javanica are found in winter. Other duck species recorded in small numbers include Anas acuta, A. crecca, A. querquedula, A. clypeata and Aythya nyroca. The site is important for wintering raptors. In addition to many Circus (aeruginosus) spilonotus and C. melanoleucos, two Aquila clanga and one A. heliaca are recorded annually over the feshwater marshes.

More than 3,000 wintering shorebirds of up to 42 species may, at times, be present on the foreshore and in adjacent paddies. There are usually several hundred Charadrius dubius, C. mongolus, Tringa stagnatilis and T. glareola, and 100-200 Calidris ruficollis and C. subminuta. Some 20-30 Xenus cinereus and Calidris alba are regularly present on the open sandy shore. Calidris tenuirostris is annual on passage in small numbers. Other waterbirds include wintering concentrations of at least 10 Hydroprogne caspia and 45 Sterna bergii. The endangered Nordmann's Greenshank Tringa guttifer has been recorded, and may be a regular winter visitor to the area in very small numbers. Other scarcer visitors have included occasional Numenius madagascariensis, Limnodromus semipalmatus and Eurynorhynchus pygmaeus.
The freshwater marsh supports a great variety of wintering migrant passerines and is probably of conservation importance as a site for Acrocephalus spp and other warblers. It is the only known wintering site for the little-known Acrocephalus (agricola) tangorum and is the southernmost wintering area for Erithacus svecicus (and possibly many other species) in continental Southeast Asia.

The forested crags within the park support Serow Capricornis sumatraensis, an endangered species in Thailand.
Special floral values: The site presents an unparalleled variety of habitats situated in close proximity to one another.
Research and facilities: Most available information on the site has been compiled from the reports of visiting bird-watchers and from data collected by Interwader. This information is held on file at the Centre for Wildlife Research, Mahidol University, Bangkok. The National Parks Division staff at the site have themselves compiled a bird list. Accommodation is available at the National Park headquarters.
References: Bijisma & de Roder (1985); Lekagul et al. (1985); Parish & Wells (1985); Pirawat (1986).
Criteria for inclusion: 1e, 2a, 2b, 2c, 3b.
Jira Jintanugool and Philip D. Round.