Forest Preserve District of Cook County, Illinois
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Big Weasels
Nature Bulletin No. 512-A   January 12, 1974
Forest Preserve District of Cook County
George W. Dunne, President
Roland F. Eisenbeis, Supt. of Conservation

The Weasel Family includes the mink, skunks, otters, badger, martens and wolverine as well as the bloodthirsty little weasel -- all carnivorous fur-bearers having a pair of anal glands containing musky fluid which, except in the otters, badger and fisher, has a vile penetrating odor.

The Pine Marten or American Sable, a little smaller than a house cat, is the tree-living member of the family. It dens and does much of its hunting in trees where it is a deadly enemy of squirrels and birds. On the ground it preys on marmots, chipmunks, hares, mice, grouse and reptiles. Honey, nuts and berries are eaten also. Aside from the lynx, eagles, owls and the fisher, a marten's chief enemy is man.

Because of its intense curiosity, this beautiful animal is one of the easiest of all fur-bearers to trap and the pelt is very valuable. Its fur, exceptionally thick and soft, is a rich golden brown shading into black on the legs and bushy tail. There are large patches on the neck and chest. Until the white man came, a few martens lived in Cook County but it is a shy wilderness creature and soon disappeared. Now they are found only in the dense coniferous forests of remote regions in Canada, Alaska and our northwestern states.

The Fisher, called Pekan by trappers, is another marten but larger -- about the size of a fox -- much fiercer, and spends more time on the ground. Although it prefers swampy lowland forests and is a good swimmer, it is not as aquatic as an otter or even a mink, and fish are only incidental in its diet. The name "fisher" was probably invented to distinguish it from the pine marten. The long silky fur, varying from grayish brown to dark brown or almost black, is in great demand but this wary animal is difficult to trap and very scarce.

There are fishers in the Adirondack forests of New York, the mountainous wildernesses of our northwestern states, and across Canada from Labrador to Alaska and British Columbia, but they have never been abundant anywhere. Even 150 years ago, when fishers were seen here in Cook County and in the Appalachian mountains as far south as North Carolina, that was true.

This animal hunts, mostly at night, over a territory of several square miles. Once on the trail of a victim, it never quits and is capable of remarkable speed for short distances. On the ground it preys on snowshoe rabbits, marmots, beaver, birds and small animals; also on dead deer and fish. In the trees it preys on squirrels, raccoons, the pine marten, and porcupines. Other than a wise old wolf, a fisher is the only animal smart and quick enough to flip a porcupine over, attack the soft underbelly, and kill it without being harmed by the deadly quills .

The Wolverine or Caracajou, giant of the weasel family, is a powerful evil-tempered outlaw that looks like a bear and smells like a skunk. It is said to have attacked and killed deer, caribou, moose and even mountain lions. In winter it will follow a trapper's route, eat the trapped animals, hide or wreck the traps and break into his cabin where it destroys and defiles what it cannot devour.

Almost four feet long and weighing from 25 to 35 pounds, the wolverine has a broad powerful head, thick body and short sturdy legs. Its long thick hair dark brown except for a broad band of yellowish white along each side, is used in the far north to trim parkas because it will not accumulate frost.

Michigan is known as the Wolverine State. Although extinct, now, east of The Rockies, this beast once ranged from the Arctic Ocean south into our northern states. If there ever was a cunning demon, this is it.

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