The Hairy-nosed otter is a semiaquatic mammal native to Southeast Asia and one of the rarest and least known otter species. It has a short brown fur that becomes paler on the belly. Its rhinarium (the tip of the snout) is covered with short hair. The upper lip and chin are whitish. Some individuals are reddish-chestnut in color. Its body is long, its tail slender, and its fully webbed paws have prominent claws.
Hairy-nosed otters occur in Southeast Asia from southern Thailand, Cambodia, southern Vietnam, and Peninsular Malaysia to Sumatra and Borneo. They inhabit lowland flooded forests, peat swamp forests, mangroves, flooded grasslands, shallow coastal waters, rivers, and wetlands.
Hairy-nosed otters live in coastal areas and on larger inland rivers, solitary or in groups of up to 4 individuals. They are active during the day spending most of their time hunting their prey. During the dry season, they typically forage in drainage canals and ponds. The contact call between Hairy-nosed otters is a single-syllabic chirp. Adult females call to their pups with staccato chatter.
Not much is known about the breeding habits of Hairy-nosed otters. Populations in the Mekong Delta possibly breed in November and December, and in Cambodia between November and March. The gestation period lasts around 2 months and a family of both parents and pups were sighted between December and February.
The Hairy-nosed otter is the rarest otter in Asia, most likely verging on extinction in the northern parts of its range and of uncertain status elsewhere. The species is threatened by the loss of lowland wetland habitats, hunting for fur and meat, and accidental killing during fishing.
There is no overall population estimate available for the Hairy-nosed otter. However, there are estimates of its populations in U Minha National Park that includes around 50-230 individuals. Currently, this species is classified as Endangered (EN) on the IUCN Red List and its numbers today are decreasing.