Grizzlies are massive animals with humped shoulders and an elevated forehead that contributes to a somewhat concave profile. The fur is brownish to buff, and the hairs are usually silver- or pale-tipped to give the grizzled effect for which they are named. Large adult grizzlies may be about 8 feet long and weigh about 900 pounds. Their eyesight is poor, and they have been known to attack humans without evident provocation. Females with cubs are the most aggressive.
Grizzlies once ranged through forested and open regions of western North America from Alaska to Mexico. Formerly living across the Great Plains, the grizzly bear has been the subject of many Native American legends and was one of the mammals reported by Lewis and Clark in their journey through eastern Montana in 1804.