Weasels are small, slender carnivores mainly found in the Northern Hemisphere. They belong to the genus Mustela , which includes ferrets, polecats, minks, and ermines. Weasels have tube-like bodies, small flattened heads, flexible necks, and short limbs. Their fur is short and dense, typically brown with white or yellowish underparts, but some species coats turn white in winter. They have five toes on each foot with sharp, curved claws. These bold and aggressive predators hunt alone, eating mice, voles, rats, rabbits, frogs, birds, and eggs. Their narrow bodies allow them to pursue prey into burrows and crevices. Male weasels mate with multiple females and do not provide parental care.

What does a weasel look like?

Weasels are small carnivores with slender, elongated bodies, typically found in the Northern Hemisphere. They have small, flattened heads, long, flexible necks, and short limbs. Their fur is short and dense, usually brown with white or yellowish underparts, though some species turn white in winter for camouflage. The tail is slim and pointed, and each foot has five toes with sharp, curved claws. Weasels can be differentiated by size, color, and tail length. The least weasel is the smallest living carnivore, measuring 11–26 cm (4–10 inches) in length and weighing only 25 grams (0.9 ounce). The largest terrestrial mustelid is the wolverine, measuring up to 1.2 meters in length and can weigh up to 20 kg (44 pounds) or more.

Where do weasels live?

Weasels are small, slender carnivores found mostly in the Northern Hemisphere. They belong to the genus Mustela , which includes 17 species of ferrets , polecats , mink , and ermine . The most common and widely distributed species are the stoat and the least weasel, whose ranges extend into polar regions. The Patagonian weasel is a larger mustelid of the South American Pampas. Zorilles, or African striped polecats, are often found in agricultural areas, while the African striped weasel is found in Africa south of the Congo Basin. Some weasel species that live in colder, northern climates swap their brown fur for white fur in the winter.

Weasels are carnivores that are bold and aggressive predators that generally hunt alone. Their diets consist primarily of mice, voles, rats, and rabbits, but they will also eat frogs, birds, and bird eggs. Because of their narrow bodies, weasels can pursue and capture rodents in their burrows and chase them through holes and crevices, under dense herbage, up trees, or into water. Weasels cannot accumulate fat and must eat frequently, so they often kill more prey than they can immediately consume and will store excess food for later use.

How do weasels hunt and catch their food?

Weasels are known as bold and aggressive predators that typically hunt alone. Their diet consists mainly of mice, voles, rats, and rabbits, but they will also eat frogs, birds, and bird eggs. Their narrow bodies enable them to pursue and capture rodents in their burrows, as well as chase them through holes and crevices, under dense herbage, up trees, or into the water. Because weasels cannot store fat, they must eat frequently. They often kill more prey than they can immediately consume and will store excess food for later use.

What role do weasels play in their ecosystems?

Weasels are bold and aggressive predators that play a crucial role in their ecosystems by controlling rodent populations, but they also eat frogs, birds, and bird eggs. Their slender bodies enable them to hunt rodents in burrows and other tight spaces. Weasels consume more prey than they can immediately eat and store the excess for later, impacting local prey dynamics. The stoat, a type of weasel, was introduced to New Zealand to control rabbits but became a threat to native birds, illustrating the complex and sometimes detrimental impacts of introducing predators into new environments.

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Related Topics:: least weasel; African striped weasel; long-tailed weasel; tropical weasel; Patagonian weasel

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Top Questions

What is a weasel?
Weasels are small, slender carnivores mainly found in the Northern Hemisphere. They belong to the genus Mustela, which includes ferrets, polecats, minks, and ermines.

Weasels have tube-like bodies, small flattened heads, flexible necks, and short limbs. Their fur is short and dense, typically brown with white or yellowish underparts, but some species coats turn white in winter. They have five toes on each foot with sharp, curved claws.

These bold and aggressive predators hunt alone, eating mice, voles, rats, rabbits, frogs, birds, and eggs. Their narrow bodies allow them to pursue prey into burrows and crevices. Male weasels mate with multiple females and do not provide parental care.
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What does a weasel look like?
Weasels are small carnivores with slender, elongated bodies, typically found in the Northern Hemisphere. They have small, flattened heads, long, flexible necks, and short limbs.

Their fur is short and dense, usually brown with white or yellowish underparts, though some species turn white in winter for camouflage. The tail is slim and pointed, and each foot has five toes with sharp, curved claws. Weasels can be differentiated by size, color, and tail length.

The least weasel is the smallest living carnivore, measuring 11–26 cm (4–10 inches) in length and weighing only 25 grams (0.9 ounce). The largest terrestrial mustelid is the wolverine, measuring up to 1.2 meters in length and can weigh up to 20 kg (44 pounds) or more.
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Where do weasels live?
Weasels are small, slender carnivores found mostly in the Northern Hemisphere. They belong to the genus Mustela, which includes 17 species of ferrets, polecats, mink, and ermine. The most common and widely distributed species are the stoat and the least weasel, whose ranges extend into polar regions. The Patagonian weasel is a larger mustelid of the South American Pampas. Zorilles, or African striped polecats, are often found in agricultural areas, while the African striped weasel is found in Africa south of the Congo Basin.

Some weasel species that live in colder, northern climates swap their brown fur for white fur in the winter.
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What do weasels eat?
Weasels are carnivores that are bold and aggressive predators that generally hunt alone. Their diets consist primarily of mice, voles, rats, and rabbits, but they will also eat frogs, birds, and bird eggs.

Because of their narrow bodies, weasels can pursue and capture rodents in their burrows and chase them through holes and crevices, under dense herbage, up trees, or into water. Weasels cannot accumulate fat and must eat frequently, so they often kill more prey than they can immediately consume and will store excess food for later use.
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How do weasels hunt and catch their food?
Weasels are known as bold and aggressive predators that typically hunt alone. Their diet consists mainly of mice, voles, rats, and rabbits, but they will also eat frogs, birds, and bird eggs.

Their narrow bodies enable them to pursue and capture rodents in their burrows, as well as chase them through holes and crevices, under dense herbage, up trees, or into the water. Because weasels cannot store fat, they must eat frequently. They often kill more prey than they can immediately consume and will store excess food for later use.
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1. weasel
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What role do weasels play in their ecosystems?
Weasels are bold and aggressive predators that play a crucial role in their ecosystems by controlling rodent populations, but they also eat frogs, birds, and bird eggs. Their slender bodies enable them to hunt rodents in burrows and other tight spaces.

Weasels consume more prey than they can immediately eat and store the excess for later, impacting local prey dynamics. The stoat, a type of weasel, was introduced to New Zealand to control rabbits but became a threat to native birds, illustrating the complex and sometimes detrimental impacts of introducing predators into new environments.
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Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

weasel, any of various small carnivores with very elongated slender bodies. Most live in the Northern Hemisphere and belong to the genus Mustela, which in addition to weasels proper includes 17 species of ferrets and polecats as well as the mink and the ermine. Along with their tubelike bodies, weasels have small flattened heads, long flexible necks, and short limbs. The fur is short but dense, and the slim tail is pointed at the tip. Five toes on each foot end in sharp curved claws. The species can be differentiated by size, colour, and relative length of the tail.

Weasels are usually brown with white or yellowish underparts. In winter the coats of weasels living in cold regions turn white. Their pelts, especially that of the stoat (M. erminea), are known as ermine in the fur trade. The kolinsky (kolinski), also called the Siberian weasel (M. sibirica), is also much valued for its fur. The tail hairs are used to make artists’ paintbrushes.

Weasels are bold and aggressive predators. They generally hunt alone, feeding principally on mice, voles, rats, and rabbits, but they also take frogs, birds, and bird eggs. Because of their narrow bodies, weasels are able to pursue and capture rodents in their burrows and to chase them through holes and crevices, under dense herbage, up trees, or into water. Although proficient at catching mice, weasels are also notorious for raiding chicken coops. Because they cannot accumulate fat and thus must eat frequently, weasels often kill more prey than they can immediately consume and will store excess food for later use. This explains the carnage often seen after they discover captive domestic fowl.

Dromedary camels (Camelus dromedarius). Animals, mammals.

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least weaselLeast weasel (*Mustela nivalis*) in the Bering Land Bridge National Preserve, Seward Peninsula, Alaska. The least weasel is the smallest living carnivore, measuring only 11–26 cm (4–10 inches) in length and weighing only 25 grams (0.9 ounce).

Male weasels mate with multiple females and do not provide parental care. Most species have a single litter per year, but the common, or least, weasel (M. nivalis) often has two. Sexual maturity is rapidly attained, and least weasels often breed at three months of age. Litter size varies from three to a dozen or more in some species. The young are born after a gestation period of anywhere from 35 days to more than 10 months, the latter because of delayed implantation of the fertilized egg.

The most-common and most widely distributed species are the stoat (called the short-tailed weasel in North America) and the least weasel. The range of both extends into polar regions. The stoat was introduced into New Zealand to control rabbits, but instead it became troublesome and now endangers many of the country’s native birds. The least weasel is the smallest living carnivore; the smallest subspecies inhabits North America. It measures 11–26 cm (4–10 inches) in length and weighs only 25 grams (0.9 ounce). Larger forms of the same species occur in Russia and adjacent countries, where they are somewhat longer and considerably heavier. The range of the stoat and the least weasel overlap, and in those areas the species can be differentiated by the stoat’s black-tipped tail. In North America the largest weasel is the long-tailed weasel (M. frenata); in South America it is the tropical weasel (M. africana). Both measure 25–30 cm (about 10–12 inches), excluding the 10–20-cm (4–8-inch) tail; weight is 85–350 grams (3–12.3 ounces). With most weasels, males are usually twice the size of females.

zorilleThe zorille (*Ictonyx striatus*), which is also known as the African striped polecat, is commonly found in agricultural areas. Its geographic range spans most of Africa south of the Sahara and outside the Congo basin.

Weasels belong to the family Mustelidae, and there are three weasel genera in addition to Mustela. The Patagonian weasel (Lyncodon patagonicus) is a larger mustelid of the South American Pampas. It is about 30–35 cm (12–14 inches) long, excluding the 6–9-cm (2.5–3.5-inch) tail. That weasel is grayish with dark brown underparts and a white stripe running across the forehead to the sides of the neck. The zorilles, or African striped polecats (two species of the genus Ictonyx), are somewhat smaller and are often found in agricultural areas. Their bodies are spotted black-and-white, and the tail, face, and back are striped. The African striped weasel (Poecilogale albinucha) is found in Africa south of the Congo Basin. Similar in habit to weasels of the genus Mustela, it is striped in light yellow and black, with black underparts and a long white tail.

This article was most recently revised and updated by Mic Anderson.

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