The Javan gibbon (Hylobates moloch) is a tailless ape living in the rainforests of Java. Its body length is about 45–65 cm and its weight about 4–9 kg. It is diurnal and primarily frugivorous, also consuming leaves and flowers. Arboreal in habit, it moves by brachiation and typically lives in small family groups of about four individuals consisting of a male, a female, and offspring. Unlike other gibbons, it often sings alone. Gestation lasts about seven months and usually results in a single infant; because maturation and subsequent reproduction take time, its capacity for recovery is low. Due to forest destruction and hunting, the population is considered to be under 4,000 individuals and it is listed as Critically Endangered (IUCN Category I B).