Scientific Name: Ursus americanus
Kingdom:
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Ursidae
Genus: Ursus
Distribution
The American Black Bear is the most common bear species native to North America. It lives throughout much of the continent, from northern Alaska south into Mexico and from the Atlantic Ocean to the Pacific Ocean. This includes 41 of the 50 U.S. states, all Canadian provinces except Prince Edward Island, and some of Mexico. Populations in the Southern United States remain in the protected mountains and woodlands of parks and preserves, though bears will occasionally wander outside the parks' boundaries and have set up new territories, in some cases on the margins of urban environments in recent years as their populations increase. Although there were probably once as many as two million Black Bears in North America long before European colonization, the population declined to a low of 200,000 as a result of habitat destruction and unrestricted hunting. By current estimates, more than 800,000 are living today on the continent.
Physical Characteristics
The American Black Bear usually ranges in length from 150 to 180 cm (5 to 6 feet) and typically stands about 76 to 91 cm (2.5 to 3 feet) at the shoulder. Standing up on its hind feet, a Black Bear can be up to 7 feet tall (2.12 m). Males are 33% larger than females. Females weigh between 40 and 180 kg (90 and 400 pounds); males weigh between 115 and 275 kg (250 and 600 pounds). Adult black bears can reach 300 kg (660 pounds), but exceptionally large males have been recorded from the wild at up to 240 cm (95 inches) long and at least 365 kg (800 pounds). The biggest American Black Bear ever recorded was a male from North Carolina that weighed 881 lbs (400 kilograms). At the other extreme, very small adult bears can weigh as little as 39 kg (85 lbs) in females and 47 kg (103 lbs) in males. Cubs usually weigh 200 to 450 g (between 7 ounces and 1 pound) at birth. The adult has small eyes, rounded ears, a long snout, a large body, and a short tail. It has an excellent sense of smell. Though they generally have shaggy black hair, the coat can vary in color from white through chocolate-brown, cinnamon-brown, and blonde (found mostly west of the Mississippi River), to black in the east (the same is generally true in Canada, the border being between Manitoba and Ontario). They occasionally have a slight V-shaped white chest blaze. The tail is 4.8 inches (12.12 cm) long.
Reproduction
Females generally reach breeding maturity at 3 to 4 years of age and with adequate nutrition can breed every 2 years. In poor quality habitat, they may not mature until 5-7 and may skip breeding cycles. Males are sexually mature at the same age, but may not become large enough to win breeding rights until they are 4-5 years old (they have to be large enough to win fights with other males and be accepted by females). Mating is generally during summer, from mid-June to mid-August with some variation depending on latitude, but with embryonic diapause, the embryos do not begin to develop until the mother dens in the fall to hibernate through the winter months. Because of this delay, gestation can be 7 to 8 months, but actual development takes about 60 days. However, if food was scarce and the mother has not gained enough fat to sustain herself during hibernation as well as produce and feed cubs, the embryos do not develop.
Diet
Black bears are omnivores whose diet includes plants, meat, and insects. They are apex predators in North America, with the exception of areas where they coexist with the brown bear. The black bear eats a wide variety of foods, mainly herbs, nuts and berries. In the state of Washington and other parts of the Pacific Northwest, black bears eat a large amount of skunk cabbage, horsetail and tree bark during the spring. They also commonly feed on spring acorns in Massachusetts.
They feed on carrion and insects (mainly for the larvae) such as carpenter ants, yellow jackets, bees, wasps and termites. They raid beehives for both honey and bee larvae as both are easy sources of carbohydrates (honey) and protein (larvae.) They also kill and eat small mammals (such as rodents) and ungulates, mostly the young. In Michigan and the state of New York, black bears prey on white-tailed deer fawns. In addition they have been recorded preying on elk calves in Idaho and moose calves in Alaska. Additionally, black bears will eat salmon, suckers, alligator eggs, crayfish, and trout and will seek out food within orchards, beehives, and agricultural croplands. They may frequently raid garbage dumps, campsites, or appropriate food from the trash bins of businesses or private homes.
