Brown bears eat mostly vegetation. They supplement their diets with the meat of animals such as fish and small mammals, when it's available.
Brown bears eat mostly vegetation. They supplement their diets with the meat of animals such as fish and small mammals, when it's available.
Photograph by Paul Nicklen

Brown Bear

As winter approaches, brown bears prepare for a long winter sleep.

Common Name:
Brown Bear
Scientific Name:
Ursus arctos
Type:
Mammals
Diet:
Omnivore
Group Name:
Sloth, sleuth
Average Life Span In The Wild:
25 years
Size:
5 to 8 feet
Weight:
700 pounds

During the fall, a brown bear eats practically around the clock, stocking up for the four to seven months when it'll have to live off stored body fat. A brown bear may chow down on 90 pounds of food each day.

As the cold swoops in, the fattened bear waddles into a den among rocks or one it dug out among tree roots. The female brown bear enters her den pregnant with one (sometimes two or three) baby bears. The tiny bear, about the size of a chipmunk, is just strong enough to crawl into a position where it settles in to nurse. A female brown bear's milk is very rich in fat and calories, so the cub grows quickly.

By the time the adult bear wakes up in the spring, her baby is strong enough to follow her out of the den. Cubs live with their mothers for up to three years, and then they're usually ready to face life on their own.

Not all brown bears are grizzlies: Grizzly bears are a subspecies of brown bear.