Mammals: Long-Tailed Weasel

The old wildlife researcher, dressed in army surplus wool and a wool hat plugged along the trail in his snowshoes. He had used an old trick garnered from one of his mentors, and was curious to see if it had worked. As he ambled up to the set, he saw that it did not. The Long-Tailed weasel had bounded at the target and had vanished. He knelt, studied the escaping bound tracks, and re-adjusted the trail camera set...

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The Long-Tailed Weasel (Mustela frenata) is the largest and most widely distributed of the three North American weasels residing in Montana. This species is characterized by a small head, dark beady eyes, small ears and a pointed nose. They have a long slender body, elongated neck, and the longest tail of the weasels present in Kootenai Country Montana. Adult males are larger than females. Summer pelage is dark brown on its back and flanks with whitish-yellow underparts. Long tails have a black tip on the tail year round, and no whitish line down the inside of the legs. The feet are dark brown in summer. In winter, these weasels acquire a white coat. Total length averages about 14 inches, and they weigh in at approximately 7 ounces.    

Habitat wise, these weasels are found in most terrestrial habitats near water in Northwest Montana. They usually avoid overly dense forests, and are often found in mixed coniferous forests of median age. Often, edge effects are used as well as riparian stringers of deciduous and evergreen trees. Diet includes field mice, voles, snowshoe hare, western cottontail rabbits, chipmunks, pine squirrels, shrews, birds, bird eggs, frogs, bats, earthworms and insects.    

Observing long tailed weasels hunting in the wild is an adventure! Though mainly nocturnal, they can also be active during the day. These white winter weasels are terrestrial, but are also good swimmers and can also climb trees. They usually nest in old burrows of other animals, but do not stay in their dens long. These ferocious and aggressive predators hunt with inexhaustible energy, and persistent investigation of every nook, cranny, small hole, bush, or rock pile it comes across. Long-tails will track prey by following the scent trails left, and usually employ an ambush and pounce strategy. These slender slaughtering hunters can make quick kills by piercing the base of the preys skull with their sharp teeth.    

Long-Tail Weasels sometimes hunt in pairs, but are more often solitary hunters. When alarmed, they may emit a strong musky odor, and stomp their feet. Front tracks are larger and more symmetrical than the rear tracks generally. Average front tracks are 1 inch long and 1 inch wide, and average rear tracks are 1 inch long by 3/4 inch wide. Bounding stride in snow is about 20 inches. These hunters mark their trails with musky smelling urine and scat. The main predators of the long-tails are owls, hawks, red fox, coyotes, bobcats, and lynx. During winter in Kootenai Country Montana, these handsome snow white weasels kill and are killed. And so the cycle of life continues.    

(Author’s Note: Reference-Montana Trapper’s Association Publications. Unprotected predator status in Montana.)