Asian short-clawed otter

Asian short-clawed otter(Aonyx cinerea)

Phylum —chordata
Class — mammalia
Order — carnivora
Family — mustelidae

Genus – aonyx

Appearance

The Asian short-clawed otter has deep brown fur with some rufous tinge on the back, but paler below. Its underfur is lighter near the base. The sides of the neck and head are brown, but its cheeks, upperlip, chin, throat and sides of the neck are whitish.The muzzle has long coarse vibrissae on either side. Its eyes are located toward the front of the head. The small ears are oval-shaped with an inconspicuous tragus and antitragus. Its paws are narrow with short digits that are webbed to the last joint. There are short hairs on the lower sides of the interdigital webs. The claws are short, almost erect, and in some individuals even absent. Females have four mammary glands.

In head-to-body length, it ranges from 470 to 610 mm (18.4 to 24 in) with a 260 to 350 mm (10.2 to 13.6 in) long tail. The tapering tail is thick and muscular, especially at the base, and more than half the length of the body. Hind feet are 97 to 102 mm (3.8 to 4 in) long.

Habitat

The Asian short-clawed otter inhabits coastal regions in southern India to southern China and the Malay Peninsula.

Behavior

These otters are the most social amongst the otter species and live in extended family groups numbering 12-20 individuals. These animals are diurnal, inhabiting in remote areas, generally free of human disturbance, though some have adapted to living near villages. They groom their fur continually to maintain the insulating qualities. They are excellent swimmers, swimming by moving their back legs and tail. After swimming or feeding, they tend to rub against logs and vegetation in the area in order to leave their scent, a form of 'scent marking'. They usually rest and sleep on land either in their dens or somewhere above ground, often sleeping in areas of moderate disturbance. Asian short-clawed otters are often seen playing in water (this is observable at zoos) and sliding down muddy banks in regions they frequently visit. They defend their territory by scratching, working and occasionally fighting.

Diet

Asian short-clawed otters are carnivores, they eat frogs, crabs, shellfish and crayfish.

Reproduction

Asian short-clawed otters will form a monogamous pair for life. The alpha pair is the only one that breeds and the previous offspring help with raising the young. Breeding occurs throughout the year, two litters per year sometimes produced. After gestation of 60 days the litter of 1-6 (average 2) is born in their nesting burrow in the muddy riverbank. The males help make the nest burrow and bring food once the pups are born. Pups are relatively undeveloped when born, with eyes closed and weighing only two ounces (50 gm). The first few weeks are spent nursing every 3-4 hours. They open their eyes at around 40 days and venture outside after about 10 weeks. Pups begin eating solid food at around 80 days, and weaning takes place at about 14 weeks. They can swim when about 3 months old. Young reach their adult size after about 6 months.

In captivity

Asian short-clawed otters live up to 12 years in human care, with some individuals living longer than 20 years.

Keeping an otter in captivity is not simple. Moreover, this is difficult in an urban-type apartment, since the otter can not be kept in the room all the time, although it is quite easy to train it to go to the toilet — in a box with sand. However, its excrement has an unpleasant smell. Therefore, when keeping otters at home, it is good to have your own yard, where you can make an aviary.

In this enclosure, the bottom and walls can be made of animal breeding mesh with metal corners at the junction of the bottom and walls. Under the netting lining the bottom, you should put about 20 cm of coarse gravel. The same material should be used to fix the lower part of the wall to a height of 15 cm. The same layer of river sand should cover the lower grid inside the aviary. The optimal size of the aviary is 5-10 m. The enclosure must have a pool 0.5—1 m deep. The area of its water pool should be at least 2 m, but its optimal ratio with the land area in the enclosure is 1:2. It is better to make the pool elongated, 1 m wide. For otters, a genetically fixed habitat is a water pool-the ground, so this elongated shape of the water area of the pool is optimal. Near the pool there is an otter dryer in the form of a box with a hygroscopic substrate: dry sand, peat, sawdust of deciduous trees, dry rot from rotted trunks. Such a box should contain a certain excess of lying otter. Another element of the interior of the otter enclosure is a shelter. Preferably, it should be two-chambered if the owner wants to get its offspring in the future. The entranceof the first chamber looks like the passage to the outside in the form of a rectangle of about 20 cm long and with the smallest possible cross-section area. It is covered with a sponge along the perimeter. The small area of the entrance section should be covered with a sponge on the inner perimeter. It is necessary for maximum extraction of water from the otter's hair if it tries to get wet into the shelter. The living chamber of the shelter should have an internal area sufficient for the dense lying of an adult female and its several kids. The approximate size of these premises is of 40x30x25 cm. The entrance hall can be about 25 cm long. The common shelter cover should be waterproof, possible to be raised, but heavy enough that the otters could not lift it. The lifting cover will make cleaning easier and it will be more convenient to replace wet hay with dry one, which is puton the floor. The walls of the shelter for insulation should be made double: the outer - of boards, and the inner- of plywood. It is recommended to put the sawdust between the walls in a layer of 2-4 cm.

The most important thing when keeping an otter in captivity is the selection of its diet, which provides an optimal combination of the necessary chemical elements and substances, both in composition and in calories. In the special literature, many different diets for otters are proposed. We present a kind of compromise option that combines numerous recommendations from specialists and specific opportunities. So, the weekly diet for an otter should consist of 50-80% meat and 10-30% fish. The rest can be filled with milk, butter, eggs, and frogs. Do not forget about multivitamins and substances containing calcium and phosphorus. All that you need to give the otters on a weekly basis, especially vitamins. Like other species of marten, pregnant female otters kept in captivity must be provided with sufficient vitamin and mineral nutrition. Therefore, daily food should be mixed with a child's daily allowance of multivitamins and add calcium carbonate or gluconate, as well as lay out pieces of chalk. Fish food should include not only herbivores, but also predatory fish species. The daily rate of food offered to the otter should be 0.5 kg.

Otter should be vaccinated annually against viral infections (carnivore plague), as well as against gastroenteritis, viral hepatitis, botulism and others, which are vaccinated against domestic dogs.