The short-tailed weasel (Mustela erminea) lives in the northern temperate regions of North America and Eurasia. These animals have typical weasel form: a long thin body, a long neck, short legs and a small head. The fur on their underside is pale, and the rest of their fur is reddish-brown to black for most of the year. During winter their fur turns white, to camouflage them in the snow. This winter coat inspires "ermine," another name for this animal. Ermine is a French word meaning "white winter color."
Habitat and Home Range
Short-tailed weasels live in woodland areas around lakes and rivers. They require heavy underbrush for hiding when they stalk their prey, but they tend to avoid dense forests. They are solitary creatures, and maintain exclusive home ranges by scent-marking and patrolling their boundaries. Home ranges span across 25 to 50 acres, depending on the quantity and density of food sources in a range. Males' home ranges may cover twice as much territory as those of females. Ermine build burrows within their home ranges but sometimes take over abandoned burrows or nests of their prey.
Like most weasels, these animals are true carnivores. They prey on mammals rabbit-size or smaller. Short-tailed weasels will consume voles, shrews, rabbits, rats, chipmunks and other small mammals in their habitats. When such animals are scarce, short-tailed weasel will turn to birds, eggs, frogs, fish and insects. Males tend to chase and consume larger prey than females.
Short-tailed weasels hunt primarily at night. When they spot potential prey, they rush to overtake the animal quickly, sinking their teeth into the back of the victim's neck and head. They kill their prey by biting the base of the animal’s skull repeatedly. Because short-tailed weasels must eat at least once a day, they store extra food in case hunting is unsuccessful later. When their favored supply of mammals is scarce, they will go after animals such as insects that are easier to catch. In the summer, they’ll also consume fruit and berries.
Ermine move quickly, both aboveground and in underground tunnels and burrows. Females prefer to hunt in underground tunnels; males more often hunt on the surface. A weasel moves carefully, investigating every hole and crevice. When tracking its prey, it moves in a zigzag pattern to escape detection. Short-tailed weasels may travel over 9 miles in one night in search of food. These solitary animals do not hunt together, and do not associate with other ermine except while mating.
Jennifer Mueller began writing and editing professionally in 1995, when she became sports editor of her university's newspaper while also writing a bi-monthly general interest column for an independent tourist publication. Mueller holds a Bachelor of Arts in political science from the University of North Carolina at Asheville and a Juris Doctor from Indiana University Maurer School of Law.