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Mustela frenata

Long-tailed Weasel

Order: Carnivora
Family: Mustelidae

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Image of Mustela frenata
Mustela frenata - winter coat, left; summer coat, center; "Bridled Weasel", right
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Conservation Status: Least Concern.

Long-tailed Weasels are voracious predators, foraging day and night for small vertebrates, and scavenging for carrion when necessary. In captivity, adults can consume an amount equal to one-third their own body weight in 24 hours. In the wild they may store food in a burrow or near a kill site. They are solitary except for the July-August breeding season. Both males and females maintain territories, marking them with chemical secretions from anal glands. Litters usually comprise 4-5 pups, born in a den. In 12 weeks they reach full adult body weight and begin hunting for food, pursuing mates, and establishing territories. Foxes, raptors, Coyotes, domestic dogs and cats, and rattlesnakes all prey on Long-tailed Weasels, and although they can live in a variety of habitats, population densities are low. In some locations they are endangered, and in others, considered threatened or species of concern.

Also known as:
Bridled Weasel

Sexual Dimorphism:
Males are larger than females.

Range: 330-420 mm males; 280-350 mm females

Range: 160-450 g males; 80-250 g females


Lichtenstein, M.H.C., 1831.  Darstellung neuer oder wenig bekannter Saugethiere, pl. 42 and corresponding text.


Mammal Species of the World

Mammalian Species, American Society of Mammalogists' species account

Distribution of Mustela frenata

Image of Mustela frenata
Click to enlarge. (119kb)

Image of Mustela frenata
Click to enlarge. (64kb)