Overview
The grizzly is a powerfully built bear with long, thick hair that varies in color from dark brown to pale yellowish-brown. (The so-called Toklat grizzly from the Alaska Range is a striking pale golden color with chocolate-colored lower parts.) The body is massive and thick, with a prominent hump on the shoulders and a huge head supported by a short, muscular neck. The facial profile is concave. The front claws often exceed 3-3/4 inches (95 cm) in length, and are used primarily for digging and as weapons.
Taxonomy
- Kingdom
- Animalia
- Phylum
- Chordata
- Class
- Mammal
- Family
- Ursidae
- Genus
- Ursus
- Species
- Ursus arctos
Habitat
Adaptable to a wide range of terrain and climate, including tundra, forests, mountains, and semi-deserts. Distribution- In pioneer times, grizzly bears were common in most of western North America from Alaska to northern Mexico, and from the western coastal mountains eastward to the Great Plains. The largest remaining populations today are in Alaska and Canada. Grizzlies are found in all parts of Alaska except for the range of the Alaska brown bear (Game Management Units 1-10 and 14-18). In Canada, they are found mainly in British Columbia and the Yukon, but also in western Alberta and southwestern Northwest Territories, particularly in the Mackenzie Mountains. (The common grizzly gives way to the barren-ground grizzly east of the Mackenzie River Delta and north of the tree line in the Northwest Territories and Nunavut.) There are a few isolated populations in the 48 conterminous United States, especially in Montana, Wyoming and Idaho, plus Yellowstone and Glacier national parks. Survivors may still exist in a remote area of Mexico's Sierra Madre Occidental.
Diet
Except for polar bears, grizzlies are the most carnivorous of bears. They kill animals as large as moose and elk, dig rodents from their burrows, and eat spawning fish and carrion. Nonetheless, the grizzly cannot obtain enough meat to sustain itself, and must rely on vegetable matter for much of its intake, eating grasses, sedges, roots, tubers, buds, berries and nuts.
Behavior
Except during the mating season from the end of May to late June, grizzlies are solitary and unsociable (excluding mothers with cubs). The female breeds every 2 or 3 years, with typical litters of 1 to 4 cubs born in the den during January or February. Mother bears keep their young with them for two years before separation. This bear dens in the fall and sleeps until April; however, if its sleep is disturbed, it can come to life quickly. Senses of smell and hearing are excellent, eyesight not as good, but able to make out moving objects at a considerable distance. Surprisingly agile, it can run 30 mph (48 km/h) on the flat, and can gallop for miles over steep mountain slopes. An excellent swimmer, it crosses large rivers and lakes that are many miles in width. Cubs can climb trees, but mature bears cannot because their claws are too long and their bodies too heavy.
Hunting
The grizzly is one of the finest hunting trophies on the North American continent. (Theodore Roosevelt considered it the top trophy.) For a big bear with a big skull, one should search the salmon rivers of British Columbia or of Alaska north of Unit 18. Interior or mountain grizzlies run smaller than the coastal salmon-eaters because they have less to eat. (Observing a grizzly eating berries on a mountainside, one wonders how the nourishment obtained can possibly compensate for the energy expended.) Interior grizzlies make up for their lack of size by having a beautiful coat of long, thick hair that comes in a variety of colors. A highly satisfactory way of hunting grizzlies is the classic fall horseback hunt for several species. Here, the sheep rifle is generally used for the bear as well; while a bit light, it will suffice with good bullets and good shooting. A grizzly is smaller than an Alaska brown bear, but just as tough and probably more dangerous.
Conservation Status
The species as a whole is listed as Least Concern by IUCN, but the classification does not distinguish this subspecies. More information is needed to ascertain the current population dynamics of the Common Grizzly bear. The grizzly can survive only in wilderness, because it coexists poorly with man. Considered dangerous to humans, and with a history of feeding on livestock, it has been exterminated over large areas. The Mexican grizzly (subspecies nelsoni), formerly of northern Mexico and southwestern New Mexico, but now probably extinct, was listed as endangered by the USF&WS (1970) and the IUCN, and is on Appendix I of CITES (1975).