Alternate name: Ermine

Family: Mustelidae, Weasels view all from this family

Description A short-tailed weasel with a dark tail tip and (typically) white on feet. Smaller than Long-tailed Weasel, with a relatively shorter tail (less than 44% head-body length). Males are 40-80% larger than females; animals can also be sexed by genital morphology. Back is brown in summer. Winter coat is white, with a black tail tip.

Dimensions 219-343mm, 65-90mm, 67-116g; / 190-292mm, 42-70mm, 25-80g

Similar Species Smaller than Long-tailed Weasel.

Breeding Breeds in summer, but delayed implantation results in 4-9 young born in spring, in a burrow or hollow log. Young reach adult size by about 6-7 weeks, and mothers teach the young to hunt by going out in family groups.

Habitat Alpine & subalpine habitats, Cities, suburbs & towns, Forests & woodlands, Grasslands & prairies, Lakes, ponds, rivers & streams, Meadows & fields, Scrub, shrub & brushlands, Swamps, marshes & bogs

Range Plains, Great Lakes, New England, Mid-Atlantic, Rocky Mountains, Southwest, California, Northwest, Eastern Canada, Western Canada, Alaska

Discussion Primarily a nocturnal hunter of mice, young rabbits, and other small prey. Uses most habitats in range, the widest variety of all mustelids.