Nakai–Nam Theun


The Nakai–Nam Theun National Biodiversity Conservation Area in Laos, is one of the last remaining wildernesses in Southeast Asia. Nakai–Nam Theun NBCA covers approximately 3,445 km2 of the Annamite Range and the adjacent Nakai Plateau in Khammouane and Bolikhamxay Provinces. The reserve headquarters is in Nakai, the administrative centre of Nakai District.

Rivers

From north to south, riversheds in the conservation area consist of those of the following rivers:
All are tributaries of the Nam Theun to the southwest in the Nakai Plateau.

Habitat

A series of surveys conducted since 1994 by the co-operative programme of the Wildlife Conservation Society, the Lao Department of Forestry, and the World Conservation Union have revealed that the area has a high biodiversity conservation value. Semi-evergreen forest, deciduous dipterocarp forest and stands of pine are all found on the Nakai Plateau and in the Annamite foothills to the east, grading into more exclusively evergreen forests as the land rises towards the Vietnamese border. Higher still, huge areas of montane fagaceous forest cloak the slopes, interspersed with patches of Fokienia hodginsii, a commercially valuable cypress-like conifer. On mountaintops and above c. 2,000 m the fagaceous forest gives way to more stunted, rhododendron-dominated ericaceous cloudforest.

Flora

Species of plants listed as threatened by IUCN include conifer Cephalotaxus mannii. The only known population of Vietnamese White Pine in Laos is in Nakai–Nam Theun.

Fauna

Mammals

Species of mammals, some discovered relatively recently, include the following:
More than 400 bird species have been identified in Nakai–Nam Theun and the adjacent northern extension. This is by far the highest avian species richness of any site yet surveyed in Laos and is the highest recorded in a single protected area in Southeast Asia.

Languages

Many endangered Vietic languages are spoken in the Nakai–Nam Theun Conservation Area. The Vietic peoples are the indigenous peoples of the Nakai–Nam Theun area, and have deep knowledge of the local ecology. The Saek language, which preserves many archaic phonological features not found in any other Tai language, is also spoken in the area, often alongside Vietic languages in the same villages. Saek speakers had lived in the area for about 300 years, and had originally come from Vietnam. Bru speakers had moved to the area in the 1800s and 1900s, and now make up the majority of the population. Lao and Vietnamese speakers, most of whom are recent migrants, are also found in the area.