Several biodiversity surveys have been undertaken in the Middle Mahakam Watershed Area. At least 298 birds species, 147 fish species, two crustacean species, 6 aquatic reptile species, 24 mammal species including five primate species and 300 species of trees. Red list vulnerable or (critically) endangered status species include Siamese crocodile, false gharial, proboscis monkeys, giant freshwater stingray, smooth-coated and small-clawed otter, orangutan, Southeast Asian box turtle. Bornean river turtle, Asiatic softshell turtle, lesser adjutant, Wallace eagle and Storm’s stork.