• Choose a category
• All
• Classic-Fiction

By Root 1300 0

New England two species of weasels molt from brown in summer into a new white coat in winter in response to day-length changes. They retain, however, the black tip on the end of their tails. (In other warmer parts of their range—weasels are found as far south as Florida—both species remain brown year-round.) Three other northern weasels are also native to New England: the mink, the pine marten, and the fisher. None of the three changes its pelage color. All are members of the Mustelidae, the remarkable family that includes wolverines, otters, skunks, ferrets, and badgers (including the memorably named African honey ratel). Of those occurring locally, all remain active during winter, except the striped skunk, which becomes semidormant and lives off its fat.

Of the two species of weasel that turn white in the winter, the long-tailed weasel (Mustela frenata) does not extend far into Canada, whereas the ermine (Mustela erminea, also known as the stoat, in England) has a more northerly and circumpolar distribution. In the field it is practically impossible to distinguish these two. Males of both species weigh about twice as much as females, and M. frenata are about twice as large as the ermine. Undoubtedly at least some of the “ermine” that used to decorate the coats of European aristocracy was in fact long-tailed weasel. Both came from the trappers in North America.

Weasels, at first glance, seem to be designed wrongly. They are beautifully camouflaged in white, yet that conspicuous black tip of a tail seems an odd, inexplicable anomaly—until experiments showed that hawks easily captured fake weasels that had no black-tipped tail. When the hawks were baited with fakes that had black-tipped tails, however, the birds grew confused, either momentarily hesitating or attacking the tails as though they were the head-end. Other small animals also use such deception-evolved tails. Many lizards, for example, have colorful, conspicuous tails that divert or distract predators. The tail is easily detachable, and starts writhing and flailing after being detached, to divert the predator even more from the rest of the animal that slinks away. Lycaenid butterflies also have similarly distracting and detachable “tails” on their wings that fake out a predator in much the same way a good basketball passer fools his opponent on the court. The butterflies’ tails imply to a predator that its prey is about to head in one direction, when it then turns and escapes in the opposite.

Weasels are consummate mouse predators, but they are not restricted to a diet of mice. A 1999 study of least weasels (Mustela nivalis), which are native to North America north of New England, and to Alaska, Europe, and Siberia) shows that small rodents (mostly voles) constitute 41 percent of their diet in summer when they also eat birds, eggs, and insects. In winter they subsist primarily on small rodents.

The flexibility of these predators is noteworthy. Weasels readily climb trees; the pine marten in particular is known for its tree-hunting of squirrels. So skilled are weasels that in Wytham Woods, near Oxford, England, the population of tree-hole-nesting great tits was reduced by 50 percent before predator-proof nest boxes were constructed. I’ve been told by Maine woodsmen that in the winter, weasels will even catch snowshoe hares, a feat I find difficult to imagine as the largest weasel that I have weighed is a Mustela frenata male of 283 grams. An adult snowshoe hare weighs five times as much. However, weasels are not intimidated by a size disadvantage. My neighbor near my Maine cabin told me of seeing a white weasel in November in close pursuit of a hare.

The mustelids’ ability to kill large prey may involve more than brawn, as evidenced by the finesse fishers display while preying on porcupines, which no dog can subdue or eat. They display a curiosity and willingness to acknowledge the new. I suspect they are fairly intelligent. The long skulls of all mustelids, from weasels to otters, indicate a remarkably large brain volume for such a small animal. According