Dam Doi (Ngoc Hien) Bird Colony
Location:	8°56'N, l05°13'E; near the southern tip of the Mekong Delta, 5 km SSE of Dam Doi District Town and 70 km southwest of Bac Lieu, Dam Doi District, Minh Hai Province.
Area:	119 ha.
Altitude:	0.5m.
Biogeographical Province:	4.5.1.
Wetland type:	07.
Description of site:	A small patch of mangrove forest with trees at least three metres in height, bounded to the northwest by the Dam Doi River and some 17 km from the coast of the East Sea. The Bay Hap canal and many small streams flow through the area. The forest is subject to tidal inundation, with flooding to a depth of one metre. The salinity is 20 p.p.t. The mangrove forest was formed in 1960; although it was sprayed with toxic chemicals during the war, the damage was not very serious and the forest remains in good condition. The site was colonized by nesting waterbirds in 1964, and now holds the largest breeding colony of waterbirds in southern Vietnam.
Climatic conditions:	Tropical monsoonal climate with a pronounced dry season from December to April and a rainy season during the southwest monsoon from May to November. The average annual rainfall is 2,360 mm (minimum 1,940 mm, maximum 2,818 mm), the mean annual temperature is 25.5°C (minimum 15.3°C, maximum 30.3°C), and the mean relative humidity is 85.6%.
Principal vegetation:	Mangrove forest dominated by species of Avicennia (50%), Bruguiera (33%) and Rhizophora (7%). The forest presents a three-storeyed appearance with a well-developed upper stratum at 15-20m dominated by Avicennia alba and A. officinalis. Other species include Rhizophora apiculata and Bruguiera parviflora. The middle stratum with trees 8-l0m in height consists of Excoecaria agallocha, Ceriops tagal, Phoenix paludosa and Nypa fruticans. The ground flora includes Acrostichum aureum with Acanthus ebracteatus. Lianasa are abundant in exposed Sites and include Derris trifoliata and Flagellaria indica.
Land tenure:	The site is owned by the Forest Department of Dam Doi District; surrounding areas are owned by the District Department of Agriculture and agricultural cooperatives.
Conservation measures taken:	The site was declared a protected area by the National Government in 1985. Seven guards have been appointed to protect the bird colony, but the level of protection is poor.
Conservation measures proposed:	Protection measures should be enforced and some management carried out to improve the site for breeding waterbirds. The canals leading into the bird colony should be fenced off to prevent access by poachers, and guard posts should be built at critical points around the perimeter of the colony. A programme of environmental education for the general public should be initiated to improve local attitudes to the nesting birds. The Working Group on Wetlands and Waterbirds plans to organize a short training course on waterbirds and wetland management for the reserve staff.
Land use:	Nature conservation.
Possible changes in land use:
Disturbances and threats:	There is a considerable amount of illegal harvesting of eggs and young birds for food and for sale in local markets. This heavy exploitation is thought to have been responsible for the recent decline in numbers of birds.
Economic and social values:	The large bird colony is thought to be beneficial to agriculture in surrounding areas, because many of the birds feed on insects and other pests in rice fields. The birds' excrement supports the production of algae and zooplankton which provide a food source for shrimps and fishes in the wetlands around the colony. The spectacular concentrations of birds attract many visitors and could be promoted as a major tourist attraction.
Fauna:	The Dam Doi sanctuary holds the largest breeding colony of waterbirds in southern Vietnam. An estimated 100,000 individuals were present at the height of the breeding season in June, July and August in the late 1970s, but numbers have declined markedly in recent years, apparently because of illegal exploitation of eggs and young birds for food. The main breeding species are Phalacrocorax carbo, P. niger, P. fuscicollis, Anhinga melanogaster (6-10 individuals), Ixobrychus sinensis, I. cinnamomeus, I. flavicollis, Nycticorax nycticorax, Ardeola speciosa, Bubulcus ibis, Egretta garzetta, E. intermedia, E. alba, Ardea purpurea. A. cinerea, A. sumatrana, Mycteria leucocephala, Anastomus oscitans (8-10 individuals), Threskiornis melanocephalus (1,500-2,000 individuals) and Plegadis falcinellus (1,500-2,000 individuals). Other waterbirds occurring in the sanctuary include Tachybaptus ruficollis, Amaurornis phoenicurus, Gallicrex cinerea and Gallinula chloropus. The Milky Stork Mycteria cinerea is an occasional visitor to the colony but no longer breeds in the area. Other fauna includes the otter Lutra perspicillata, various fruit bats, the python Python molurus, monitor lizards Varanus sp and frogs of the genus Rana.
Special floral values:	None known.
Research and facilities:	Some preliminary surveys and censuses have been carried out at the colony, but no detailed studies have been made.
References:	Le Dien Duc (1984); Le Dien Duc & Le Dinh Thuy (1987); Phung Trung Ngan (1987); Vo An ha & Nguyen Dinh Dien (1985); Vo Quy (1984); Va Quy & Le Dien Duc (1984).
Criteria for inclusion:	2c, 3a.
Source:	Le Dien Duc.