Asian Small-Clawed Otter

The **Asian small-clawed otter** (*Amblonyx cinerea*, syn. *Aonyx cinereus*), also known as the **oriental small-clawed otter** or simply **small-clawed otter**, is a semiaquatic mammal native to Southand Southeast Asia. It is a member of the otter subfamily (Lutrinae) of the weasel family (Mustelidae), and is the smallest otter species in the world. Its paws are a distinctive feature; its clawsdo not extend beyond the fleshy end pads of its partially webbed fingers and toes. This gives it a high degree of manual dexterity so that it can use its paws to feed on molluscs, crabs and other small aquatic animals.

The Asian small-clawed otter inhabits mangrove swamps and freshwater wetlands in South and Southeast Asia. It lives in extended family groups with only the alpha pair breeding; offspring from previous years help to raise the young. Due to ongoing habitat loss, pollution, and hunting in some areas, it is listed as Vulnerable on the IUCN Red List.

## Physical Description

These otters have dark brown fur above and lighter fur below, often with gray, white, or cream-colored markings on the face and throat. They have webbed feet, and true to their name, their claws do not extend beyond their digital pads.

**Size**

The smallest of the 13 otter species, weighing less than 10 pounds (4.5 kilograms) and measuring up to two feet (61 centimeters) long—with 10 to 14 inches (25 to 35 centimeters) of that being tail.

## Habitat

Asian small-clawed otters are found in southern India, southern China, Southeast Asia, Indonesia and the Philippines. These otters live in small streams, rivers, marshes, rice paddies, seacoasts and in mangroves. They share their habitat with three other species of otter: Eurasian, smooth coated and hairy nosed.

## Communication

Asian small-clawed otters are a very vocal species and have a vocabulary of at least twelve different vocalizations. Vocalizations are used for contact, summons, greeting, threat and alarm calls and can occur visually, chemically, or through tactile cues such as social grooming, hormonal changes and posturing.

These otters also use scent markings as an important form of communication. With paired scent glands at the base of the tail, otters emit an intensely musky smell that can delineate territory and communicates information concerning identity, sex, sexual receptivity and time elapsed between scenting visits. They tend to defecate or spray in communal latrine areas to pass on this information.

## Food/Eating Habits

In the wild the otters eat primarily crustaceans and mollusks but will also eat fish, insects, amphibians and reptiles. Asian small-clawed otters use their forepaws rather than their mouth to locate and capture food items. Incomplete webbing between the toes gives them a great deal of manual dexterity. They have sensitive digital pads that help them feel under rocks or in murky water for food. They dig in sand and mud at the shoreline for various types of shellfish (clams and mussels) and crabs. To get at the meat, they either crush the shell by hand or let heat from the sun open the shells. Their teeth are broad and robust, well suited for crushing shells.

At the Smithsonian's National Zoo, Asian small-clawed otters are fed a prepared meat diet called Natural Balance, small fish such as smelt and capelin, canned feline diet and kibble. Like domestic cats, Asian small clawed otters have a propensity to develop kidney stones, so they are given cat food which includes ingredients that prohibit the growth of these stones. They are also given crabs, mussels, clams, mealworms, crickets, live crayfish and live goldfish as enrichment items. With a very rapid metabolism, otters have boundless energy, but a meal passes through their system in just a few hours. Because of this, they are fed multiple times a day.

## Social Structure

This is a social species, living in family groups of up to 15 to 20 individuals. Although they live in groups, they hunt by themselves

## Reproduction and Development

Small-clawed otters start exhibiting breeding behavior around six months old, although they generally are not sexually mature until one and a half years. The most successful breeding occurs between 1.5 and 3 years old. Once they are mature, they can breed year-round. They dig nesting burrows called holts into the muddy banks where they live. The female's estrous cycle is 28 days, with a three-day period of estrus. After a gestation period of 68 to 72 days, females give birth to a litter of one to six pups. Typically, two litters of pups are born each year, 8 or 9 months apart. All members of the family group help feed and care for the young.

## Lifespan

Asian small-clawed otters live up to 15 years in human care, with some individuals living longer than 20 years. Lifespan in the wild is unknown.