Hoolock Gibbon (Bunopithecus hoolock) is a small (about 6 kg) arboreal and diurnal ape seen in India, limited to the southern bank of the Dibang - Brahmaputra
River system. It lives in tropical wet evergreen, tropical semi-evergreen and sub tropical moist deciduous forests, up to an altitude of 1400 m. Generally it eats fruits and leaves. Hoolock Gibbon is found in small monogamous family groups which consist of an adult mated pair with sub adult, juvenile and infant offspring. The animal is also a good swimmer. It can be seen in Gibbon Wildlife Sanctuary, Assam.