The month of August heralds the migration of salmon, and this represents a dream come true for hungry bears. Male bears can land as many as 50 salmon per day, each fish providing 2,500 to 6,000 calories. When the fish are most abundant and the pickings are easy, bears can afford to be choosy and feed on the prime bits — the skin, brain and caviar, all high in fat. Bears augment this rich diet with nuts and berries, also high in protein. Bears can eat up to 16 hours each day, consuming incredible quantities of soapberries, buffaloberries or huckleberries. The goal is a condition known as hyperphagia — excessive eating and weight gain. It would be considered an eating disorder among humans, but for bears it is an absolute necessity if they hope to make it through the long, deep sleep of winter.
The extra fat, however, can make it difficult for bears to stay cool in the August heat. Bears slow down considerably in the summer sun — they can't move faster than 3 miles-per-hour without running a fever. Much of their time is spent swimming, lying in cool water, and resting in the shade. A bear's hot spots include the ears, muzzle, nose, footpads and especially the inner thighs and armpits. The combination of huge meals and the heat make it a commonplace sight to see bears lying spread-eagle — obviously content to simply rest and digest.