American Mink

Neovison vison

The mink is a medium-sized member of the weasel family. The first American mink were brought to British fur farms in 1929 and all wild mink in Britain today are descendants of escapees. The natural wild colouring is a glossy dark brown, appearing almost black in some light. Commercial farming selectively bred much paler colours, hence most of those in the wild in Britain are a lighter brown.

Mink spend up to 80% of their time in their dens, sleeping, grooming and eating food they have carried home. Frequently found near water, they are often mistaken for otters, although mink are in fact considerably smaller.

Mink are a major factor in the decimation of the water vole population, because they are small enough to follow their prey down its burrow. However, recent research indicates that where the otter population has increased, due to cleaner rivers, mink have declined.

Origin: Introduced from North America.

Size: Male: length of head/body 42 cm plus tail 18 cm. Female: length of head/body 36 cm plus tail 15 cm.

Description: Elongated body, relatively short legs, limited webbing between the toes, glossy dark brown coat, commonly white fur patches on chin, throat, chest and groin.

Habitat: May be seen on every kind of waterway, streams, rivers, and canals, but are capable of living away from water provided prey, such as rabbits, small mammals and birds, is available.

Young: Delayed implantation delays the 30 day gestation period to 39 – 42 days. Kits are born in a den lined with vegetation in April – May. One litter, 4 – 6 young. At 10 weeks they cease to depend on their mother for food. They learn to hunt with their mother. In August they disperse in search of their own territories. Females settle within 5 km of their place of birth, males 10 km

Nest: May have 2 – 10 dens close to their favourite hunting grounds, usually made in the eroded roots of oaks, sycamores or willows.

Diet: Rabbits, ducks, water voles, shrews, fish, frogs, crayfish, eels, moorhens, rats, birds and eggs are all taken by the mink.

Population: Pre-breeding season estimated to be 110,000 and declining.