least weasel

mammal

Also known as: Mustela nivalis, Mustela rixosa, common weasel(Show More)

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July 23, 2026

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The least weasel (Mustela nivalis) is the smallest known carnivore. This mammal is found in northern North America, Eurasia, and Africa. In summer, its fur is brown on top and white underneath, and in winter, it typically turns completely white in colder regions.1

Least weasels have elongated, slender bodies, small heads, long necks, and short limbs. They possess sharp, curved claws on each foot. Their diet primarily consists of small rodents like mice and voles, but they will also prey on frogs, birds, and eggs. Their narrow bodies allow them to pursue prey into burrows and tight spaces.2

Unlike some other weasel species, the least weasel often has two litters per year and can reach sexual maturity as early as three months old. The term "dwarf weasel" is another name for the least weasel.23

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carnivore
Form and function
…member of Carnivora is the least weasel (Mustela nivalis), which weighs only 25 grams (0.9 ounce). The largest terrestrial form is the Kodiak bear (Ursus arctos middendorffi), an Alaskan grizzly bear that is even larger than the polar bear (Ursus maritimus). The largest aquatic form is the elephant seal (Mirounga…
Read More
…member of Carnivora is the least weasel (Mustela nivalis), which weighs only 25 grams (0.9 ounce). The largest terrestrial form is the Kodiak bear (Ursus arctos middendorffi), an Alaskan grizzly bear that is even larger than the polar bear (Ursus maritimus). The largest aquatic form is the elephant seal (Mirounga…
Read More