The black bear in the mountains is active sometimes by day and sometimes by night. Probably it is principally nocturnal but active by day only when the food obtained at night is insufficient to meet the needs of the animal. In the lowlands it is almost completely nocturnal. In the mountains it enters upon its winter sleep with the first snows or, if the snows are late, when the huckleberries are gone. Ordinarily black bears are in "hibernation" by the middle of November. In the lowlands of western Washington they are active until after the salmon spawning season, and probably do not "hibernate" before the middle of December and may not do so at all. In the mountains they emerge from the winter sleep in May; in the lowlands they emerge in February or March. The black bear is omnivorous in the truest sense of the word. Because the animal is of large size it requires much nourishment. This is obtained by eating large quantities of material with low food value. Material eaten passes rapidly through the digestive tract and often only easily digested parts seem to be utilized. Feces commonly contain complete and undigested berries and seeds or almost undigested pieces of apples or other fruit. The principal food of the black bear in Washington is berries. Many species are eaten, but the huckleberry (_Vaccinium_ sp.) is favored. Other food items are: _Gaultheria shallon_ (pulpy fruit); Oregon grape, _Berberis nervosa_ (flowers and fruit); salmonberry, _Rubus parviflorus_ (leaves and fruit); leaves of several plants, including _Rubus macropetalus_ and other thorny kinds; grass, succulent plants, and roots. Insects are eaten and most feces show remains of a few. In June, 1938, near Cle Elum, Kittitas County, a species of sword-tailed cricket fully two inches in length was abundant, and droppings of a bear there were composed entirely of the remains of these crickets. Fish, especially spawning salmon, are important food. When salmon are spawning the bears in the vicinity feed on nothing else. Warm-blooded vertebrates probably are eaten but none of the many bear droppings examined by me contained remains of birds or mammals. Bennett, English and Watts (1943: 30) found few mammals to be eaten by bears studied by them in Pennsylvania. Locally bears kill pigs and sheep, smash bee-hives and raid fruit trees.