Forest Preserve District of Cook County, Illinois
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The Musk Ox
Nature Bulletin No. 740   January 25, 1964
Forest Preserve District of Cook County
Seymour Simon, President
David H. Thompson, Senior Naturalist

Why are bones of the arctic musk ox found here in Illinois? The evidence shows that these remains date back to the Ice Age when mile- deep ice sheets covered Canada and large parts of the United States, Europe and Asia. At that time the musk ox was one of the few hardy animals that thrived along the edges of these ice sheets. Then, for thousands of years, as the climate warmed and the glaciers melted, the musk oxen followed the retreating glaciers northward. Today, they survive only on the bleak tundras of Alaska, northern Canada and the coast of Greenland .

The musk ox looks somewhat like a small, unusually shaggy buffalo. It is built and upholstered for life in the most rugged climate on earth, where blizzards howl and temperatures 50 degrees below zero are common. Adult bulls weigh 500 pounds or more but appear heavier because of their thick padding of hair and wool. Cows are smaller. The dark brown to black hair -- two feet or longer on the neck, chest, sides and hind quarters -- hangs like an ankle-length skirt. The horns of both sexes are sharp, vicious weapons.

Unlike their arctic neighbors, the barren grounds caribou, musk oxen do not migrate southward with the coming of winter They feed on patches of dwarf willows swept free of snow by the wind and dig with their hoofs to uncover mosses and lichens. With the coming of the brief arctic summer musk oxen feast and grow fat on the abundance of grasses and sedges that quickly shoot up. The calves, born in May, are weaned and on a vegetarian diet by late summer.

Each spring the musk ox tears off its old wool underwear and grows a new suit. At this time, no other animal could look more ragged and moth-eaten. The dense, soft wool works out through the long hair and hangs in loose patches or long fluttering streamers until they are scraped off on rocks and shrubs. The new suit gives almost complete protection against the clouds of mosquitoes and blackflies that torture other warm-blooded creatures during the arctic summer.

No other animal has the defense method of musk oxen. When danger threatens they do not run away. Instead, a herd of twenty to forty individuals backs into a rough circle facing outward with the calves in the center or under their mother's bellies. This ring of horned heads can defy such natural enemies as the arctic wolf and the grizzly bear. From time to time a bull dashes out to do battle, then returns to the circle. He is exceedingly nimble. A single sweep of his horns can cripple or kill a wolf, dog or Eskimo hunter armed with a spear.

This habit of forming a defense circle has almost doomed the musk ox in modern times. A man with a gun can stand at a safe distance and wipe out an entire herd at his leisure. Eskimos and Indians with rifles in their hands for the first time had an orgy of killing. The Alaskan herds were wiped out and those of northern Canada and Greenland reduced to a few thousand animals.

In an effort to rebuild the population, Canada has forbidden the killing of musk oxen by either natives or whites. The Royal Canadian Mounted Police carefully investigate any signs or reports of killing. The United States has reestablished them in southwestern Alaska from a band of 34 animals brought from Greenland in 1930.

The name comes from a pair of musk glands below the eyes of the bulls. When in the defense circle facing an enemy, or in duels between males for control of the herd, the bulls perfume themselves by furiously rubbing their massive heads against their forelegs.

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