Fish Biodiversity in the Mekong Basin

The Mekong River system hosts one of the most diverse and prolific freshwater capture fisheries in the world with around 850 fish species recorded and up to 1,200 estimated. The fisheries are crucial for millions of rural people as sources of employment, income, food and nutrition. The Lower Mekong countries stand out as a region of the world with the highest freshwater fish biodiversity per square kilometre. Thailand and Viet Nam are among the top 12 countries in the world having the largest number of freshwater fish species. The Tonle Sap Basin in Cambodia has the highest freshwater fish biodiversity (estimated 296 species) in the world after the East African lakes. The Lower Mekong has three main ecological fish groups: white fishes (37%), black fishes (13%) and Grey fishes (50%). Recent Research at the Kunming Institute of Zoology indicates 186 fish species in the Upper Mekong, known as Langcang River in Chinese. About half of the fish species are also found in the Lower Mekong Basin. Interestingly, almost half of the species are endemic to the Mekong.