Wetlands of Nepal constitute an important ecosystem that harbors a large number of endemic wildlife species, many of which are on the brink of extension. It is estimated that about 750,000 hectares (nearly 5 percent of the total surface area of the country) of wetlands exist in Nepal. Some 240 wetland sites are known to exist in Nepal of which, IUCN, the World Conservation Union, has already inventoried 163 in the Terai (Southern plains) region. The wetlands of Nepal, however, range from the torpid ponds of the subtropical Terai to the glacial lakes of the High Himalayas which indicates the diversity in the species of wildlife that might be expected to be supported by them.
It is believed that 190 species of water fowl - including resident species, migratory species and uncommon and rare resident species - inhabit these wetlands. In addition to this, numerous other mammals, fishes, reptiles, and birds are found in these habitats. At least two crocodile species found in the wetlands of Nepal have now become threatened.
Nepal is signatory to a number of international conventions and treaties to protect the environment and biodiversity. Three of these are of special importance in relation to the conservation of the wetlands:
- Convention on Wetlands of International Importance, especially Waterfowl Habitat (Ramsar Convention), signed on 17 December 1987,
- Agreement on the Network of Aquaculture Centres in Asia and the Pacific, signed on 8 January 1988, and
- Convention on Biological Diversity, signed on 15 June 1992.
This shows the commitment of Nepal to conserve the wetland habitats. Several national acts, rules and regulations have also been enacted for the protection of environment and biodiversity, which also includes the wetlands, but their enforcement remains weak.
The Koshi Tappu Wildlife Reserve is the largest protected wetland and the only Ramsar site in Nepal.