Animal Field Guide

Black Bear

Ursus americanus
(Ursidae)

Global Rank: G5
State Rank: S5

Agency Status
USFWS: No Status
USFS: none
BLM: none

Coat black (often with white on chest), brown or blond; slight shoulder hump, but highest point of body above hips; muzzle staight and long in profile; claws of front feet dark, stongly curved, and shorter (seldom more than 1 1/2 inches) than those of grizzly; males weigh 180-250 lbs., occasionally up to 400; females weigh 120-180 lbs. Largly nocturnal; usually solitary; dig less elaborate dens than grizzlies, often in natural cavities (trees, rocks), under logs, brush piles, or even buildings; climb trees easily (FWP). Pelage color varies, usually black in the eastern U.S., black, brown, cinnamon, blue-black, or whitish in western North America; snout brown, straight in profile; small rounded ears; five toes on both front and rear feet; head and body length 150-180 cm, tail about 12 cm, mass about 90-140 kg for females, 115-270 kg for males (Nowak 1991, Burt and Grossenheider 1964).

Differs from the grizzly bear in having the claws of the forefeet only a little longer than those on the hind feet (about twice as long in the grizzly), length of second upper molar less than 29.5 mm (in part of range where grizzly occurs), snout profile straight rather than dished, and in lacking a prominent hump at the shoulders; maximum size of black bear is less than that of the grizzly (170-280 cm head and body length) (nowak 1991, hall 1981).

Gall bladder and paws are of great value in the Asian black market (see Boston Globe, 2 March 1992, pp. 23-24).

Non-migratory, but black bears sometimes exhibit long distance movements (JRP).

Dense forests; riparian areas; open slopes or avalanche chutes during spring green-up (FWP). Habitat use tied to seasonal food avail./plant phenology. Dry mtn meadows in early spring, snow slides,stream bottoms, wet meadows early & mid-summer. May concentrate in berry & whitebark pine areas in fall (Barnes and Bray 1967, Tisch 1961, Jonkel and Cowan 1971).

Grasses, sedges, berries, fruits, inner bark of trees, insects, honey, eggs, carrion, rodents, occassional ungulates (especially young and domestic), and (where available) garbage (FWP). Varies. Spring--primarily vegetation (grasses, umbels, & horsetails). Summer--herbaceous & fruits. Fall--berries & nuts, some begetation. Insects a frequent bomponent of diet. Also mammals, birds, & carrion (usually minor) (Tisch 1961).

Sympatric with grizzly bear but more prone to occupying closed canopy areas. Natural cub and adult mortality low, sub-adult mortality higher (Jonkel and Cowan 1971). Black bears sometimes involved in various crop/property depredations.

Similar to grizzlies, except females often first breed at 2 1/2 or 3 1/2 years of age; in very poor habitat, may not breed until 6 1/2 (FWP). Estrus 25 May-10 Aug. Peak in Jun. In NW MT 1st estrus at 4.5 years, often no litter until 6.5 years old. Ave. litter size 1.5-1.8 young/female. Litters every 2-3 years. Repro- ductive rates may be tied to softmast avail. (Jonkel and Cowan 1971).