Most Yellowstone male black bears weight 250 pounds or less, and most females weigh about 150 pounds or less. A good general rule of the black bear is that his back is nearly a straight profile. However, says Gunther, sometimes when a black bear is hunched over eating, it may appear that he has a hump on the back of his neck. The black bear's head is long with a flat brow. His ears are small and rounded, set well back on the head.
Black bears are strong and fast.
They can run up to 25 miles per hour over short distances, and they are naturals when it comes to tree-climbing. They are primarily adapted to forested areas and their edges and clearings. The grizzly bear varies from black to blonde. In the Yellowstone Ecosystem, many grizzlies have a light brown girth band. The back profile of a grizzly has two high points, one midway between the tail and front shoulders, and the other directly over the front shoulders.