rusa is a ruminant mammal of the families Cervidae, deer species in Indonesia there are four, sambar, timor deer, elk and deer Bawean.
Male Javan rusa are larger than females. Males usually weigh 152 kg, while females weigh about 74 kg. The males have a lyre-shaped, three-tined antlers, which weigh about 2.5 kg. Males and females have a rough grayish brown coat that is often coarse in appearance. Their ears are rounded and broad. The animals look short and stubby because they have relatively short legs.
Javan rusa are primarily nocturnal but they can browse and graze during the day. During the mating season, males decorate their antlers with grass and twigs to attract the females and intimidate competitors. Males are extremely vocal and aggressive towards one another. Males and females live separately most of the year, except during the mating season. Young calves stay with their mothers until they reach sexual maturity. They are gregarious, normally associating in herds.