Short-tailed weasel (Mustela erminea): The short-tailed weasel is the most abundant weasel in Wisconsin. At around a foot long, the short-tailed weasel is smaller than the long-tailed weasel and has a 2-4 inch tail with a black tip. They are similar in color to the long-tailed and, like the long-tailed, their fur may turn white in the winter. Long-tailed and short-tailed weasels can be difficult to tell apart, but in most parts of the state the short-tailed weasel is the most likely to be seen. Tail length is the only good way to distinguish between the two, but it can be challenging to tell in the wild. Like most members of the weasel family, they are nocturnal, and they consume similar prey to the long-tailed weasel. Weasels may be trapped year-round by those possessing a valid trapping license.
Long-tailed weasel (Mustela frenata): The long-tailed weasel is the largest weasel found in Wisconsin, though they are only slightly larger than the more common short-tailed weasel. They are usually 13-18 inches long with a black-tipped, 4-6 inch tail. They are brown on top with white or cream-colored throats or bellies, but like all three species of weasels in Wisconsin, their fur may turn completely white in the winter. Like all mustelids, the long-tailed weasel has delayed implantation, so they breed in July but don't give birth until the next spring. Weasels den in hollow stumps, tree roots, rock piles or under buildings and have an average of six young. Small mammals, rabbits and birds are the common prey items. All three species of weasel may be trapped year-round with a trapping license.
Least Weasel (Mustela nivalis) is the state's smallest weasel but exhibits typical mustelid form having a long, slender body and long neck. Its summer coat is chocolate-brown in color and lacks black on the tail and it molts to a white pelt during autumn (Oct-Nov). Least weasels are a grassland species found in a variety of open habitats such as marshlands, farmlands, grassy fields, and moist to wet prairies. The breeding season is typically during the spring and autumn, although it can occur throughout the year. Least weasels are among the smallest carnivores in the world and have a diet of mice, birds, eggs, insects, and young rabbits.
Long-tailed weasel (Mustela frenata): The long-tailed weasel is the largest weasel found in Wisconsin, though they are only slightly larger than the more common short-tailed weasel. They are usually 13-18 inches long with a black-tipped, 4-6 inch tail. They are brown on top with white or cream-colored throats or bellies, but like all three species of weasels in Wisconsin, their fur may turn completely white in the winter. Like all mustelids, the long-tailed weasel has delayed implantation, so they breed in July but don't give birth until the next spring. Weasels den in hollow stumps, tree roots, rock piles or under buildings and have an average of six young. Small mammals, rabbits and birds are the common prey items. All three species of weasel may be trapped year-round with a trapping license.
Least Weasel (Mustela nivalis) is the state's smallest weasel but exhibits typical mustelid form having a long, slender body and long neck. Its summer coat is chocolate-brown in color and lacks black on the tail and it molts to a white pelt during autumn (Oct-Nov). Least weasels are a grassland species found in a variety of open habitats such as marshlands, farmlands, grassy fields, and moist to wet prairies. The breeding season is typically during the spring and autumn, although it can occur throughout the year. Least weasels are among the smallest carnivores in the world and have a diet of mice, birds, eggs, insects, and young rabbits.