The grizzly bear has the reputation of being the most ferocious and dangerous mammal in North America.
Grizzlies vary widely in body shape, colour and in the shape of their heads.
The tundra grizzly is often creamy yellow on the back with brownish legs and underparts. In the Rocky Mountains, the silver-tip phase is dominant. Adults weigh from 136 to 526 kg and are prodigiously strong. Although grizzlies will, for the most part, avoid contact with humans, they are sometimes unpredictable and should be given plenty of room. They move with a slow shambling walk, the low-slung head swinging from side to side.