Mink
Order Carnivora : Family Mustelidae : Mustela vison Schreber

Description. A weasel-like carnivore about the size of a house cat and semiaquatic in habit; general color dark chocolate brown, darkest on back, and nearly black on feet and end of tail; underparts paler than back, with considerable white on midline from chin to vent; neck long, head hardly larger around than neck; tail long and moderately bushy; eyes and ears small; legs short; pelage soft and dense, overlaid with longer, blackish guard hairs. Dental formula as in the weasel. External measurements of an adult male: total length, 560 mm; tail, 190 mm; hind foot, 67 mm; of a female, 540-180-60 mm. Weight (males), 680-1,300 g; (females), 450-700 g.

Distribution in Texas. Known from eastern one-half of state westward to northern Panhandle in habitats near permanent water.

Habits. Mink are closely associated with the waterways and lakes of North America, but the smaller streams are preferred to the large, broad rivers. Along the coast they frequent the brackish marshes and, on occasion, the littoral area adjacent to the ocean. They are most common along streams partly choked by windfalls and other debris which create numerous water holes and at the same time offer concealment for the mink. Lake and marsh-dwelling mink are usually larger than those that live along streams.

Mink are active throughout the year. They are tireless wanderers and may travel several kilometers in their search for food.

The den is usually a retreat under the roots of a tree near the water, in a hole in the bank of a stream, in a pile of debris choking a stream, or in the houses of muskrats, which they kill or otherwise evict from their dens.

Their food consists of a wide variety of animals which they usually capture and kill. The fact that they are attracted to traps by carcasses of birds and other animals suggests that they also feed on carrion. Fish, frogs, clams, freshwater mussels, snakes, rats and mice, ground squirrels, muskrats, and birds constitute their main diet.

Mink are polygamous. The mating season is in January, February, and March and the four to eight young are born after a gestation period of from 39 to 76 days. At birth the young are blind, helpless, and covered with a coat of fine, short, silvery-white hair. They weigh about 6 g. When they are about 2 weeks old, the whitish hair is replaced by a dull, fluffy, reddish brown coat which, late in the year, is replaced by the adult pelage. Their eyes open at about 37 days of age and they leave the nest for the first time when about 7 weeks old. They are weaned when 8 or 9 weeks of age, at which time they weigh about 350 g. When about 5 months old, they are as large as adults.

The mink is one of the principal fur-bearing animals in the eastern United States and is one of the few animals that can be reared economically on fur farms. This is not the case in Texas, however, where mink ranked only thirteenth in numbers of individuals harvested and ninth in economic value to trappers during the 1988-89 trapping season, as determined in a survey conducted by the Texas Parks and Wildlife Department.

Photo credit: Donald F. Hoffmeister, courtesy of Museum of Natural History, University of Illinois.