The Grizzly Bear (Ursus arctos ssp.) is any North American subspecies of the brown bear, including the mainland grizzly (Ursus arctos horribilis), the Kodiak bear (Ursus arctos middendorffi), the peninsular grizzly (Ursus arctos gyas) and the recently extinct California grizzly (U. a. californicus) and Mexican grizzly bear (U. a. nelsoni). Specialists sometimes call the grizzly the North American brown bear because the grizzly and the brown bear are one species on two continents. In some places, the grizzly is nicknamed the silvertip bear for the silvery, grizzled sheen in its fur.
Most adult female grizzlies weigh 130–200 kg (290–440 lb), while adult males weigh on average 180–360 kg (400–790 lb). The average total length in this subspecies is 198 cm (6.50 ft), with an average shoulder height of 102 cm (3.35 ft) and hindfoot length of 28 cm (11 in). Newborn bears may weigh less than 500 grams (1.1 lb). In the Yukon River area, mature female grizzlies can weigh as little as 100 kg (220 lb). One study found that the average weight for an inland male grizzly was around 270 kilograms (600 lb) and the average weight for a coastal male was around 408 kilograms (900 lb). For a female, these average weights would be 136 kilograms (300 lb) inland and 227 kilograms (500 lb) coastal, respectively. On the other hand, an occasional huge male grizzly has been recorded which greatly exceeds ordinary size, with weights reported up to 680 kg (1,500 lb). A large coastal male of this size may stand up to 3 metres (9.8 ft) tall on its hind legs and be up to 1.5 metres (4.9 ft) at the shoulder. Although variable from blond to nearly black, grizzly bear fur is typically brown in color with white tips. A pronounced hump appears on their shoulders; the hump is a good way to distinguish a black bear from a grizzly bear, as black bears do not have this hump.
Brown bears are found in Asia, Europe, and North America giving them one of the widest ranges of bear species. In North America, grizzly bears previously ranged from Alaska down to Mexico and as far east as the western shores of Hudson Bay. In North America, the species is now found only in Alaska, south through much of western Canada, and into portions of the northwestern United States including Idaho, Montana, Washington and Wyoming, extending as far south as Yellowstone and Grand Teton National Parks, but is most commonly found in Canada. In Canada, there are approximately 25,000 grizzly bears occupying British Columbia, Alberta, the Yukon, the Northwest Territories, Nunavut, Ontario and the northern part of Manitoba.
Grizzly bears hibernate for 5–7 months each year. During this time, female grizzly bears give birth to their offspring, who then consume milk from their mother and gain strength for the remainder of the hibernation period. To prepare for hibernation, grizzlies must prepare a den, and consume an immense amount of food as they do not eat during hibernation. Grizzly bears do not defecate or urinate throughout the entire hibernation period. The male grizzly bear's hibernation ends in early to mid March, while females emerge in April or early May.
- Shelter: Big Cat Cave, Snow Cave
- Enrichment: Cardboard Box, Horse Dummy, Live Prey
- Animal Food: Fish, Insects, Meat, Mixed Fruit