Many subspecies are covered by the scientific name U. arctos, including the Kodiak bear and the grizzly bears. This particular race of the brown bear is characterised by its ‘grizzled’or greyish fur, thanks to the colouration at the tips of its hairs.
Roaming over vast areas, grizzly bears are mainly vegetarian, but they will also hunt a variety of prey, particularly deer of various types. They are territorial, and most attacks on people can be explained by the bear’s poor eyesight, which suggests the person is a rival bear. In spite of their weight, grizzly bears can run fast, at speeds equivalent to 60 kph (37 mph), and they can also climb and swim well. They face few dangers, apart from being hunted by man.
In late summer and autumn, the bears fatten up on vast quantities of fruit and berries in preparation for the winter sleep - a period of torpor, not true hibernation.
Distribution: Occurs in North America, being found mainly in Alaska and Canada, although small numbers still survive in the US, mainly in Wyoming, Montana and Idaho.
Weight: 150 - 600 kg (330 - 1322 lb); males are heavier.
Length: 180 - 213 cm (71 - 84 in) overall; about 150 cm (59 in) tall.
Maturity: 5 - 7 years; males may not breed until 10.
Gestation period: 186 - 248 days; embryonic development begins 5 months after fertilization.
Breeding: 2, ranges from 1 - 5; weaning occurs at 6 - 8 months.
Food: Omnivorous, eating fruit, vegetation, carrion and vertebrate prey.
Lifespan: Up to 30 years; 40 in captivity.
Broad, wide nostrils give these bears a keen sense of smell, whereas their eyes are small.
These are immensely powerful, with the legs being thick and strong.
Scratch marks made on a tree may indicate the presence of a bear.
Those grizzlies living in the far north are typically larger in size than those found further south.
The bear’s greyish flecking is a characteristic feature of this race.
Grizzly bears will take advantage of salmon returning to their traditional spawning grounds, wading into the water to catch these fish.