The wild water buffalo (Bubalus arnee), also called Asian buffalo, Asiatic buffalo and wild buffalo, is a large bovine native to the Indian subcontinent and Southeast Asia. It has been listed as Endangered in the IUCN Red List since 1986, as the remaining population totals less than 4,000. A population decline of at least 50% over the last three generations (24–30 years)[when?] is projected to continue. The global population has been estimated at 3,400 individuals, of which 95% live in India, mostly in Assam. The wild water buffalo is the most likely ancestor of the domestic water buffalo.
Bos arnee was the scientific name proposed by Robert Kerr in 1792 who described a skull with horns of a buffalo zoological specimen from Bengal in northern India The specific name arnee is derived from Hindi arnī, which referred to a female wild water buffalo; the term is related to Sanskrit áraṇya ("forest") and áraṇa ("strange, foreign.") Bubalus arnee was proposed by Charles Hamilton Smith in 1827 who introduced the generic name Bubalus for bovids with large heads, convex-shaped narrow foreheads, laterally bent flat horns, funnel-shaped ears, small dewlaps and slender tails. Later authors subordinated the wild water buffalo under either Bos, Bubalus or Buffelus.
The wild water buffalo has an ash-gray to black skin. The moderately long, coarse and sparse hair is directed forward from the haunches to the long and narrow head. There is a tuft on the forehead, and the ears are comparatively small. Its head-to-body-length is 240 to 300 cm (94 to 118 in) with a 60 to 100 cm (24 to 39 in) long tail and a shoulder height of 150 to 190 cm (59 to 75 in). Both sexes carry horns that are heavy at the base and widely spreading up to 2 m (6 ft 7 in) along the outer edges, exceeding in size the horns of any other living bovid. The tip of the tail is bushy; the hooves are large and splayed. It is larger and heavier than the domestic water buffalo, and weighs from 600 to 1,200 kg (1,300 to 2,600 lb).[15][16] The average weight of three captive wild water buffaloes was 900 kg (2,000 lb). It is among the heaviest living wild bovid species, and is slightly smaller than gaur.
The wild water buffalo occurs in India, Nepal, Bhutan, Thailand, and Cambodia, with an unconfirmed population in Myanmar. It has been extirpated in Bangladesh, Laos, Vietnam, and Sri Lanka. It is associated with wet grasslands, swamps, flood plains and densely vegetated river valleys.
Wild water buffaloes are both diurnal and nocturnal. Adult females and their young form stable clans of as many as 30 individuals which have home ranges of 170 to 1,000 ha (420 to 2,470 acres), including areas for resting, grazing, wallowing, and drinking. Clans are led by old cows, even when bulls accompany the group. Several clans form a herd of 30 to 500 animals that gather at resting areas. Adult males form bachelor groups of up to 10 individuals, with older males often being solitary, and spend the dry season apart from the female clans. They are seasonal breeders in most of their range, typically in October and November. However, some populations breed year round. Dominant males mate with the females of a clan who subsequently drive them off. Their gestation period is 10 to 11 months, with an inter-birth interval of one year. They typically give birth to a single offspring, although twins are possible. Age at sexual maturity is 18 months for males, and three years for females. The maximum known lifespan is 25 years in the wild. In Assam, herd sizes vary from three to 30 individuals.
