Grizzly Bear Ursus arctos Grizzly bears are mammals. An adult bear can measure 3-4 feet high at the shoulder and 8 feet tall standing upright. Adults weigh between 250 and 600 pounds. The color of their coat varies from blond to reddish to dark brown. They have a prominent shoulder hump, rounded ears, and claws that measure more than 2 inches in length.
Grizzly bears are omnivores .
There have always been grizzly bears in the North Cascades Ecosystem, however, many were killed by trappers, miners, and bounty hunters by 1860. The estimated current population of grizzly bears within the entire North Cascades Ecosystem is a maximum of 30-50 bears. Home ranges vary from six to 2,000 square miles, depending on food availability, age, sex, and breeding status of the bear. Home ranges of related females often overlap, and a male's home range generally overlaps with those of several females. During the cooler months of the year, grizzly bears go into a deep sleep, which many physiologists classify as a highly specialized hibernation.