Mustela frenata

Order: Carnivora
Family: Mustelidae

Status: Fur of some value, unprotected predator.

Identifying Characteristics: Largest and most widely distributed of the three North American weasels.  Distinguished by its long, slender body and long neck.  Longest tail of the North American weasels.  During summer fur rich brown on the back and sides with yellowish-white underparts, black tip on tail, and no whitish line down inside of leg.  Acquires a white winter coat.  Adult males noticeably larger than females.  Total length: 11 to 16.5 inches.  Weights: 3 to 12 ounces.

Habitat: Found in almost all land habitats near water.  Has the broadest ecological and geographical range of the North American weasels.  Prefers areas with abundant prey.  Avoids dense forest, most abundant in late seral ecotones.

Food Habits: More of a generalist than the short-tailed and least weasels.  Feeds mostly on small mammals up to rabbit-sized, but eats birds and other animals as well.

 Life History: Primarily nocturnal, but sometimes active during the day.  Quite fearless and curious.  Mainly terrestrial but can climb and swim well.  Nests in old burrows of other animals.  Mates during summer; 205 to 337 day gestation; delayed implantation; young born during April; litter size 4 to 9.

Similar Species: Short-tail weasel - white line down inside of leg, smaller.  Least weasel - no black tip on tail, smaller.  Mink - nearly uniform dark brown.  Marten - heavier, much larger.