While Malaysia has only 0.2% of the land mass of the world, it has one of the richest fauna and flora in the world, second only to Indonesia in South East Asia. Malaysia is one of the 17 mega-diversity countries in the world, hosting more than 170 000 fauna and flora species. Riverine biodiversity in Malaysia is of global significance. Malaysia has an estimated 500 species of freshwater fish, of which 300 occur in Peninsular Malaysia, 250 in Sarawak and 130 (40% of which are endemic) in Sabah. Other riverine biodiversity includes 158 species of amphibians of which 57 are endemic; 88 species of freshwater crab and 55 freshwater shrimps. At least 20 new species of fish and crabs have been described in the last 15 years indicating that the total diversity is higher. Malaysia has a broad range of aquatic ecosystems including rivers, lakes, swamps and man-made wetland habitats such as reservoirs and rice-fields, which together cover between 12-15% of the countryÔÇÖs land area. In addition to aquatic biodiversity ÔÇô riverine biodiversity includes the species of plants, birds and mammals which occur along the river corridor and upper catchment. The Kinabatangan River (one of the proposed project sites) is the largest river in Sabah with a length of 560 km, stretching from the highlands of eastern Sabah to the Sulu Sea. The floodplain covers about 4,000 km² and is one of the richest areas in terms of both river and terrestrial biodiversity. It is one of two places on the planet where ten primate species cohabitate. These are the Tarsier, Slow Loris, Pig-tailed Macaques, Long-tailed Macaques, Proboscis Monkey, Silvered Langur, Maroon Langur, Grey Langur, Bornean Gibbon, and the famed Orang Utan (Kinabatangan has the highest concentration of wild Orangutan in Malaysia). There are 50 mammal species living in the Kinabatangan area including the Sun Bear, Pygmy Elephant, Sumatran Rhino, and four species of cats, the Clouded Leopard, Leopard Cat, Marbled Cat and the Flat-headed Cat. The riparian forest provides a vital corridor for the seasonal migrations of many mammal species. Kinabatangan is one of the most productive freshwater fisheries in Malaysia with over 90 species of fish, including freshwater rays and sharks such as the giant freshwater whipray (Himantura polylepis) .and the endemic Borneo river shark, (Glyphis fowlerae)The upper Kinta Basin includes the third highest mountain in Peninsular Malaysia (Gunung Korbu) and has important forest and aquatic biodiversity ÔÇô some of the important species include rare and endangered species including tiger (Panthera tigris), Asian elephant (Elephas maximus), Malayan Tapir (Tapirus indicus) and Sun Bear (Helarctos malayanus) as well as rare plant and bird species. Endangered fish present in the river include the Seven-striped Barb, (Probarbus jullieni) or Temoleh. In recent years, the stocks of P. jullieni have declined drastically throughout Se Asia due to pressure from unsustainable fishing and habitat degradation, resulting from intensive development activities such as land clearing, deforestation and dam construction. The biodiversity of the upper reaches of the Klang river is also high with more than 95 mammal species including serow, tiger, leopard and three species of gibbon; 250 bird species, 63 reptiles, 20 amphibians, 363 butterflies. 20 new endemic species of aquatic insects described at one small site in the catchment in recent years. Most of the upper catchment has been designated as within the Selangor State Park. Rare fish species recorded include the Malaysian Mahseer or Kelah Tor tambroides.Riverine ecosystems and associated biodiversity also has significant socio-economic value ÔÇô in terms of commercial and subsistence fishery; ornamental fish culture and trade; recreational fishery (a US$300 million/year industry in Malaysia) as well as playing important roles in water supply, flood control and ecotourism. Degradation of riverine ecosystems leads to increased floods, decreased fisheries as well as loss of potential recreation and tourism revenue. Threats: Riverine biodiversity is however in serious decline in Malaysia with most rivers being affected by high silt loads from land clearing and development or urban or industrial pollution. The rivers are largely found outside of formal protected areas ÔÇô so are affected by a broad range of land use and industrial impacts as well as direct over-exploitation.