Tonle Sap Lake is the largest freshwater lake in Southeast Asia. Also called Boeung Tonle Sap, it has one of the world's most vibrant ecosystems. There are different species of wildlife in and around the lake, which helped to sustain and grow the ancient Khmer civilization.In fact, the Tonle Sap is one of the most productive fishing lakes in the world, supporting over three million people and providing over 75 percent of Cambodia's annual inland fish catch and 60 percent of Cambodians' protein intake. Its fish species richness and productivity is ranked fourth in the world.