Lang Sen IBA is situated in the Plain of Reeds, a large plain in the Mekong Delta, which was once dominated by seasonally inundated grasslands but has now been largely converted to agricultural land. Lang Sen is one of the few sites in the Mekong Delta where semi-natural Melaleuca forest occurs along a natural river channel1. The dominant habitats at the site are paddy fields and Melaleuca plantations but there also exist smaller areas of semi-natural Melaleuca forest and lotus swamp1.
Bird Fauna: Key Features
Although a survey in 1999 documented low levels of bird species richness and abundance and, in particular, a scarcity of wetland-dependent species at Lang Sen2, reports were received in 2002 of significant numbers of large waterbirds, including Sarus Crane Grus antigone and Painted Stork Mycteria leucocephala, using the site each year for short periods3. These reports indicate that Lang Sen may be an important stop-over area for large waterbirds en route between their breeding areas in Cambodia and their non-breeding areas in the Mekong Delta of Vietnam. Further bird surveys are required to assess the status of these species at the site. The commonest waterbird species at the site include Little Cormorant Phalacrocorax niger, Chinese Pond Heron Ardeola bacchus, Cinnamon Bittern Ixobrychus cinnamomeus, Yellow Bittern I. sinensis, Black Bittern Dupetor flavicollis and Spot-billed Duck Anas poecilorhyncha2.
Global Threat Status
According to local reports, significant numbers visit the site for a short period every year3.
According to local reports, flocks visit the site every year. Four captive birds, captured at the site, were observed during March 20023.
Notes: [ ] = unconfirmed record.
Biome Restricted Species: The site does not qualify under criterion A3. See Appendix 4 for details.
The site does not qualify under any secondary criterion.
As with most remaining natural wetlands in the Mekong Delta, the biggest threat to biodiversity at Lang Sen is habitat loss. The area of habitat at Lang Sen with a relatively high biodiversity value is quite small and large areas of the site have already been converted to wet rice agriculture2. In addition, most of the remaining areas of Melaleuca plantation are currently managed by the Tan Hung Forest Enterprise, whose primary objective is timber exploitation.
Currently the management status of the semi-natural Melaleuca forest is unclear, as a result of which it does not receive adequate protection2. Consequently, further encroachment into these areas and unsustainable exploitation of fuelwood and other forest products are occurring2. High levels of boat traffic on the main river channel and adjacent canals present an additional concern for the bird fauna of the site.
The low diversity and abundance of waterbirds suggests that factors other than habitat loss may be important. Hunting pressure is likely to be high at the IBA. In addition, as throughout the Mekong Delta, the effects of high pesticide use in adjacent areas of rice agriculture on bird populations are unknown but possibly significant.
Long An Provincial People's Committee proposed the establishment of a nature reserve at the site in 1994. To date, however, a protected area has not been established1.
Lang Sen is one of the demonstration sites for a full-scale GEF project entitled the Mekong River Basin Wetland Biodiversity Conservation and Sustainable Use Project, which is currently being implemented by IUCN1.
Lang Sen should be designated as a national protected area, and a management board should be established.
All harvesting of Melaleuca within the protected area boundary should cease2.
Measures should be introduced to control unsustainable levels of natural resource exploitation at the site2.
Additional bird surveys should be conducted at appropriate times of the year to clarify the importance of the site for large waterbird species, particularly Sarus Crane.
1. Birdlife International and the Forest Inventory and Planning Institute (2001) Sourcebook of existing and proposed protected areas in Vietnam. Hanoi: BirdLife International Vietnam Programme and the Forest Inventory and Planning Institute.
2. Buckton, S. T., Nguyen Cu, Nguyen Duc Tu and Ha Quy Quynh (1999) The conservation of key wetland sites in the Mekong Delta. Hanoi: Birdlife International Vietnam Programme.
3. Nguyen Duc Tu (2002) Report on a visit to Long An province, 26 to 29 March 2002. Unpublished report to the BirdLife International Vietnam Programme.