Forest Preserve District of Cook County, Illinois
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The Grizzly and the Big Brown Bears
Nature Bulletin No. 655-A   November 12, 1977
Forest Preserve District of Cook County 
George W. Dunne, President
Roland F. Eisenbeis, Supt. of Conservation

In the early days, more tall tales were told about "Old Ephraim, " the grizzly bear, than any other animal. It had the reputation of being a bloodthirsty enemy of man and was given the scientific name Ursus horribilis by a taxonomist who had never seen a live one but had heard and read some of those yarns about its terrible ferocity and prodigious strength.

The Grizzly is very intelligent and shrewd but, actually, has a rather phlegmatic disposition. It avoids people and will not attack unless provoked. Then, a female with cubs is unpredictable, and big game hunters say that a wounded grizzly is the most dangerous animal on earth. But ordinarily, as Earnest Thompson Seton observed, Ephraim is a peaceful giant who is perfectly satisfied to let you alone if you leave him alone.

Grizzlies originally ranged from Mexico through the Sierras and the Rockies to central Alaska; and eastward across the Great Plains as far as western Texas and Minnesota. Today, except in Yellowstone, Grand Teton and Glacier national parks, and the Lewis and Clark national forest -- where they are protected -- few grizzlies survive south of Canada.

They and the Big Brown Bears of Alaska are members of a group in which 84 species and subspecies have been described. The differences between some of them are so slight that it is difficult to tell which is which and they interbreed. The true grizzlies vary in color from shades of brown to creamy yellow and jet black. There is commonly a sprinkling of white-tipped hairs on the back -- hence the name -- and they were also called Silvertips or, by Lewis and Clark for example, "white bears. "

A mature grizzly, about eight years old, may be from 6 to 8-1/2 feet long and weigh from 600 to 1000 pounds. The massive head appears dish-faced because of the high forehead, and there is a pronounced hump over the shoulders. It can run faster than a horse. With one sweep of a paw it can crush the skull of a bull or a bison, and can carry away the carcass of a full-grown steer or an elk. A grizzly's vision is poor but its hearing is keen and the sense of smell is unsurpassed.

John Muir once remarked that a bear will eat everything except granite. A grizzly, emerging from hibernation, nibbles at early vegetation such as skunk cabbage or the buds on shrubs and trees, and then hunts for carcasses of animals killed during winter by snowslides, etc. In summer it digs up roots and, much like a cow, crops great quantities of grass. It digs craters to capture ground squirrels and other burrowing animals. On a mountain side covered with berry bushes it devours armfuls of the twigs, leaves and fruit. It is as fond of pine nuts as it is of carrion, fish, ants, insect grubs and honey. Just before hibernating, hog fat, it eats nothing but quantities of spruce or fir needles.

The big brown bears, except for a species that inhabits the Barren Grounds, seldom range far from the sea coasts and become much larger than the grizzlies, possibly because, being remarkably adept at catching salmon, they eat enormous amounts of fish. Those on Kodiak Island and the Kenai and Alaska peninsulas are the largest carnivores in the world. Some of them become almost 10 feet long, measure about that from claw tip to claw tip of their outstretched front feet, and weigh 1800 pounds. "Brownies" vary in color from golden brown to creamy tan or grayish black. The several kinds differ from each other and from the grizzlies in size, teeth, and the shape and size of their skulls.

The golden grizzly, now extinct, is pictured on the state seal of California.

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