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The brown bear (Ursus arctos) is a species of bear that can reach weights of 130-700 kg (300 to 1500 pounds). The grizzly bear and Kodiak bear are North American subspecies of brown bear.

Brown bears have coats in shades of blond, brown, black, or a combination thereof; the long outer guard hairs are often tipped with white or silver, giving a "grizzled" appearance. Brown bears have a large hump of muscle over their shoulders which gives strength to the forelimbs for digging. Their heads are large and round with a concave facial profile. In spite of their size, they can run at speeds of up to 56 km per hour (35 miles per hour).

Once native to Asia, Africa, Europe and North America, brown bears are now extinct in some areas and have had their numbers greatly reduced in some others. They prefer semi-open country, usually in mountainous areas. The brown bear ranges from Alaska east through the Yukon and Northwest Territories, south through British Columbia and through the western half of Alberta. Isolated populations exist in northwestern Washington, northern Idaho, western Montana, and northwestern Wyoming. The subspecies U. arctos horribilis (the grizzly bear) includes all brown bears of continental North America; the subspecies U. arctos middendorffi (Kodiak bear) includes brown bears on the Alaskan islands of Kodiak, Afognak, and Shuyak. The range of the subspecies U. arctos nelsoni is in northern Mexico.

The brown bear is primarily nocturnal and in the summer puts on up to 180kg (400 pounds) of fat on which it relies to make it through the winter, when it becomes very lethargic. Although they are not true hibernators and can be woken easily, they like to den up in a protected spot such as a cave, crevice or hollow log during the winter months.

Being omnivores, they feed on a variety of plant parts, including berries, roots, and sprouts; fungi; and fish, insects and small mammals. Brown bears are largely vegetarian, deriving up to 75% of their dietary calories from vegetable matter. Interestingly, bears eat an enormous number of moths during the summer - sometimes as high as 20-40,000 in a day - and may derive up to 1/3 of their calories from moths.

Normally a solitary animal, the brown bear congregates alongside streams and rivers during the salmon spawn. Every other year females produce 1-4 young which weigh only one pound at birth.

Four subspecies of North American brown bear have recognized:

• Ursus arctos ssp. arctos -- brown bear;
• Ursus arctos ssp. horribilis -- grizzly bear;
• Ursus arctos ssp. middendorffi -- Kodiak bear
• Ursus arctos ssp. nelsoni -- Mexican grizzly bear, possibly extinct.

Legal status

The grizzly bear is listed as threatened in the coterminous United States. The Mexican grizzly bear is listed as endangered. The grizzly bear is state listed as endangered in Washington. In Canada, it is listed as vulnerable in Alberta, British Columbia, Northwest Territories, and Yukon Territory. Prairie populations of grizzly bear are listed as extirpated in Alberta, Manitoba, and Saskatechewan.

External links

• http://www.fs.fed.us/database/feis/animals/mammal/urar/index.html