The North American grizzly is a subspecies of the brown bear. Brown bears were once widespread in Eurasia and western North America. the subspecies is becoming increasingly rare in Eurasia, except in Russia. The North American population is vulnerable. Its range has become restricted mainly to the Rocky Mountains.

The grizzly is characterized by the high shoulder hump and by its generally concave head profile. The shoulder height is up to 1.5 m (5 ft.) and a weight of 500 kg (1,100 lb.) is not uncommon. The fur colour varies from cream and silver through cinnamon and brown to black.

Grizzly bears are omnivorous. They eat a variety of things, from fish to tubers and berries. They will also eat carrion and young hoofed animals and livestock as the opportunities arise.

Like all the bears, grizzly young are very small at birth. A newborn will usually weigh 400 g (14 oz.) or less. The cubs (usually 2 or 3) are born between January and March.

Although grizzlies will, for the most part, avoid contact with humans, they are sometimes unpredictable and should be given plenty of room; every year, bears maul or kill humans. They move with a slow shambling walk, the low-slung head swinging from side to side. They can move very quickly, however, and even horses find it difficult to evade a rushing grizzly.