Mustela vison

Order: Carnivora
Order Description: Carnivores
Family: Mustelidae
Family Description: Weasels, Skunks and Others

The mink is larger than the weasel and is usually dark brown with a white throat patch. It has a large, bushy tail that is often slightly darker than the body. Its dark fur has a beautiful sheen; its fur has brought recognition to the mink for many years. Many people have “stylishly” worn their mink coat. Mink are well adapted to their semi-aquatic riparianClick word for definition habitat. Their fur sheds water easily and they have partially webbed feet. They are very good swimmers. Total length is 19 to 28 inces (470-690 mm), tail length is 6.2 to 8.8 inches (154-220 mm), and they weigh 2 to 3.5 pounds (0.9-1.6 kg).

The mink is found throughout Alaska and Canada and most of United States except in the desert Southwest.

They prefer forested, permanent, or semi-permanent wetlands with abundant cover, marshes, and riparianClick word for definition zones. They are rarely found away from water. In Idaho, they prefer aquatic habitats at lower and middle elevations.

Mink uphold the reputation of the weasel family as predators. They prey on fish, crayfish, and frogs, which they capture while swimming. In some areas they rely heavily on muskrats for food. During the summer, up to 50% of their diet is crayfish and muskrats, but they will also take waterfowl and even meadow voles. In winter they rely less on aquatic food by continue to eat muskrats and occasionally a rabbit. When food is abundant they will cacheClick word for definition it. A researcher in Illinois discovered a mink food cacheClick word for definition of 13 muskrats, 2 mallard ducks, and 1 coot. Mink are also good fishermen; they have been observed “herding” small schools of fish into shallow water where they could capture the fish and eat them.

Mink are mainly nocturnalClick word for definition and crepuscularClick word for definition. They may reduce activity in severe winter weather. When inactive, they occupy dens in muskrat burrows, abandoned beaver dens, hollow logs, holes under tree roots, or a self-constructed burrow in a stream bank. Individuals are solitary, except during mating period and when females have young. Their home ranges are almost linearly associated with watercourses, usually about 20 to 50 acres (8-20 ha.) Male home ranges are considerably larger than that of a female. In good habitatClick word for definition, densityClick word for definition may be 9 to 22 per 2.6 km2; higher concentrations indicate abundant prey.

Mink breed from late February until early April. They give birth from early May into July. This GestationClick word for definition of 40 to 80 days (average 51) is shorter than most weasels but delayed implantationClick word for definition does occur in Mink. The embryoClick word for definition develops in about a month. Once the average litterClick word for definition of 4 to 5 young are born they develop rapidly. Young mink acquire deciduousClick word for definition teeth early and eat some meat by 25 to 30 days. They are weanedClick word for definition at 5 to 6 weeks, and they are hunting with the mother at about 8 weeks. Males may sometimes help care for young.

Status: Game species
Global Rank: G5
State Rank: S5

Important State References:
Whitman, J.S. 1981. Ecology of the mink (Mustela vison) in west-central Idaho. M.S. Thesis, Univ. Idaho, Moscow. 101pp.

Information written by Donald Streubel,© 2000
Map image provided by
Stephen Burton,© 2000
Design by Ean Harker©1999, 2000.