These mink are strong swimmers and thrive in an aquatic environment. They are shy by nature, preferring to hide away in dens during the daytime. American mink are small carnivores that live close to water, where they feed on small aquatic animals. They originally came from North America, but were brought to Europe and Asia to be farmed for their fine fur. They have since escaped into the wild and are now a common pest. They are also competition for the similar, but very rare, European mink.
Mink prefer to live in areas with plenty of cover. Their river-bed dens are generally deserted burrows made by other river mammals, but mink will dig their own burrows if necessary. Mink are active at night and dive into water to snatch their prey. They live alone and will defend their own stretches of riverbank against intruders. Two months after mating a litter of up to 5 young is born in a dry underground nest lined with fur, feathers and leaves. The young begin to fend for themselves in autumn.
Mink are known for their luxurious fine fur, which is used for clothing. Several domestic varieties of mink have been bred, each with different-coloured fur.
Farming of American mink in Europe for their fur has led to feral populations being established in the wild. This more aggressive species has driven out its European relative, to the extent that the latter is now highly endangered and restricted to just a few areas. American mink have had an adverse impact on other species too, including water volves and waterfowl (hunting young ducklings). They face few enemies, although alligators, wolves, coyotes and great horned owls naturally prey on them.
Distribution: Occurs throughout the whole of North America, apart from the arid southwestern parts of the continent. Has been introduced to Europe and South America.
Habitat: Swamps and near streams and lakes.
Weight: 0.8 - 1.8 kg (1.8 - 4 lb); males are heavier.
Length: 45 - 70 cm (18 - 28 in).
Maturity: Females 12 months; males 18 months.
Gestation Period: 30 days; embryonic development may not start for a month after fertilization.
Breeding: 2-8, average 4; weaning occurs at 6 weeks.
Food: Carnivorous, hunting small mammals and fish.
Lifespan: 2 - 3 years; up to 8 years in captivity.
The lack of white fur on the upper lips confirms that this is an American rather than a European mink.
The water-repellant fur is dense and glossy, varying from light to dark brown.
Partially webbed paws are equipped with sharp claws.
Eyes and ears
The rounded eyes are small and dark; the ears are set well back on the head.
Mink are adept at catching prey on land and in water, and fish feature prominently in their diet.
American mink can support themselves on their hindquarters.
European mink once ranged from northern Spain all the way through mainland Europe to the Ob River Valley, east of the Ural Mountains of Russia. They are now almost extinct across this range and only a few populations survive in the south of France and in Spain. European mink have never lived in the British Isles. The mink species found in Britain is the American mink, which was introduced as a source of fur. The American species has become widespread across Europe and its presence has been one of the factors in the downfall of the indigenous European mink. Other problems have been hunting and habitat destruction.
Mink have a thick coat of underfur that helps to repel water when the animal is swimming. The undercoat is especially thick in winter to enable the animal to stay warm when wet.
European mink live along the banks of rivers and lakes, where they hide in dense waterside vegetation. They may dig their own burrows or modify those of water rats and other aquatic mammals. The minks are most active at dawn and dusk. They spot their prey in the water, then pounce.
Habitat: Beside rivers and lakes.
Food: Water rodents, birds, frogs, fishes and insects.
Size: 37 cm (14.5 in); 590 g (1.25 lb).
Maturity: 1 year.
Breeding: 4 - 5 young born in April and May.
Life span: 8 years.