Otters are one of the most playful animals, often appearing to take childlike enjoyment in sliding around on muddy banks or in snow.

Life span
Up to 10 years.

Statistics
Head and body length: 55-110cm, Weight: 5-12kg.

Physical description
Although conforming to the basic mustelid body shape of a long, slim body and a skull with powerful jaws, otters show numerous adaptations to aquatic life. These include webbed toes and a powerful rudder-like tail, used for propulsion under water. Otters are capable of closing their ears and nostrils while underwater. They have two types of fur; stout waterproof guard hairs and a dense, fine underfur which provides insulation. Their fur is chestnut brown and is slightly lighter on the belly.

Distribution
The Eurasian otter is the only otter native to Britain. They're also found throughout Europe, as far north as the Arctic Circle, across most of Asia and northern Africa.

Habitat
In the British Isles, otters are found in fresh and salt water, although coastal otters like those in Scotland and the Shetlands need access to freshwater pools to clean their insulating fur.

Diet
Apart from fish, otters also feed on crustaceans, water birds, frogs and voles. They can use their whiskers as sensing organs underwater, to monitor the movements of prey.

Behaviour
Otters are solitary and are active at dusk and during the night. Although they occasionally come out in the day, they usually rest in a burrow in the river bank called a holt.

Reproduction
Otters breed all year round, with a gestation period of about 63 days, after which two or three cubs are born. These are blind at birth and are covered in a dark or grey downy fur, finally opening their eyes after 35 days.

The cubs will remain inside the holt, in a nest of straw or weeds for a further couple of weeks, before venturing out into the open with their mother. The cubs are weaned after three to four months and reach sexual maturity after two to three years.

Conservation status
Otters are listed as Vulnerable by the 2000 IUCN Red List. They have become extinct in much of their range, with many populations still diminishing. They are strictly protected by the Wildlife and Countryside Act (1981) and cannot be killed, kept or sold without a licence.