Forest Preserve District of Cook County (Illinois)
Nature Bulletin No. 655-A November 12, 1977
Forest Preserve District of Cook County
George W. Dunne, President
Roland F. Eisenbeis, Supt. of Conservation
****:THE GRIZZLY AND THE BIG BROWN BEARS
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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