Black Bear

The black bear Ursus americanus is one of the most familiar wild animals in North America today. To many campers it is both a nuisance and an exciting part of their outdoor experience. Most visitors to Canada's provincial and national parks are disappointed if they fail to catch a glimpse of a bear.

How to distinguish a black bear from a grizzly

Black bears are members of the family Ursidae, which has representatives throughout most of the northern hemisphere and in northern South America. Other members of this family that occur in North America are grizzly bears and polar bears. Both of these species are considerably larger than the black bear.

Widely distributed in North America, the black bear occurs from the east to the west coast, as far north as Alaska and as far south as Mexico. It is not found on Prince Edward Island, in northern Alberta, northern Saskatchewan, or in extreme northern Ontario. The map provides a rough outline of its range.

Although found in a variety of habitats, the black bear prefers heavily wooded areas and dense bushland. Maximum numbers are probably attained in areas of mixed coniferous deciduous forests. Densities in favourable habitats are one bear to every 3 4 km². Black bears are difficult to census because they are shy and secretive. A recent estimate of the continental population is 500 000, give or take 200 000!

Description

The black bear is a bulky and thickset mammal. Approximately 150 cm long and with a height at the shoulder that varies from 100 to 120 cm, an adult black bear has a moderate sized head with a rather straight facial profile and a tapered nose with long nostrils. Its lips, unlike those of other animals such as the wolf or bobcat, are free from the gums and can be manipulated with amazing dexterity. This adaptation and a long manipulative tongue greatly assist the bear when it feast on tiny blueberries or even tinier ants. The ears are rounded and the eyes small. The tail is very short and inconspicuous.

A black bear has feet that are well furred, on which it walks like a human being with the entire bottom portion of the foot touching the ground. Each foot has five curved claws, which it cannot sheathe. These are very strong and are used for digging and tearing out roots, stumps, and old logs when searching for food.

Owing to their compactness, bears often appear much heavier than they really are. Adult males weigh about 135 kg, although exceptionally large animals weighing over 290 kg have been recorded. Females are much smaller than males, averaging 70 kg.

The normal colour is black with a brownish muzzle and frequently a white patch below the throat or across the chest. Although black is the most common colour, other colour phases such as brown, dark brown, cinnamon, blue black, and even white also occur. Albinos are rare. The lighter colour phases are more common in the west and in the mountains than in the east. Any of these colour phases may occur in one litter, but generally all cubs in a litter are the same colour as their mother.

The eyesight of the black bear is relatively poor, but its senses of hearing and smell are well developed. A startled animal will usually attempt to get downwind from an intruder and make an identification by smell. Under favourable atmospheric conditions bears can detect carrion, which they scavenge, at considerable distances. Frequently, a black bear will stand on its hind legs with its nose in the air and scent the wind for any delectable odours.

Black bears appear awkward as they shuffle along, but can move with amazing speed when necessary. For short distances they have been clocked at speeds of up to 55 km/h. They are good swimmers and frequently cross rivers and small lakes.

Climbing is second nature to a black bear. Young animals readily take to trees when frightened. They climb with a series of quick bounds, grasping the tree with their forepaws and pushing with their hind legs. When descending they travel backwards, frequently dropping from the tree from heights up to 4.5 m. Once on the ground, they quickly disappear into the underbrush, apparently unshaken by the abrupt descent.

Although it is rarely heard, the black bear has several distinct calls. These include a growl of anger, a whining call, and sniffs of many sorts. A female with cubs may warn them of danger with a loud woof-woof and call them in with a whining or whimpering sound. The cry of a young cub in trouble is similar to the crying of a human baby.

Life history

Black bears are solitary animals, except for the close bond between females and cubs, and the pairing that takes place during the mating season. Mating is in June or early July, and the cubs are born the following January or February while the mother is still in her winter den.

Generally, two cubs are born, although there may be only one or as many as four. At birth they are 15-20 cm long and weigh slightly more than 225 g. Compared to other mammals, this is very small relative to the mother's weight. For example, a woman weighing 70 kg could expect her infant to weigh about 3 kg, 12 times the mass of the newborn bear! The young bears grow rapidly and are quite active by the time they leave the den with their mother in the spring. At one year they weigh from 13 to 27 kg but only slightly more at two years. Normally, young bears remain with their mother until they are 16-17 months old. Cubs orphaned during their first summer have about a 30 % chance of surviving to independence compared to about an 80% chance for those with mothers.

Bear tracks

Males and females may attain sexual maturity between their third and fourth years in captivity, but often later in the wild. Male bears continue to grow until their seventh year; females cease growth somewhat earlier. Bears have lived for 25 or 30 years, but most animals in the wild would be less than 10 years old.

In the autumn when days become shorter and temperatures cooler, bears begin to search for a denning site. A suitable site may be under a tree stump or overturned log, or in a hole in a hillside. Most dens are only large enough to accommodate a bear when it is curled up. Generally, females line their dens with grass, ferns, or leaves, but males usually do not. Females usually den earlier, males frequently wait until the first snowfall before entering a den.

Recent studies of black bear physiology have shown that denned bears show some characteristics of true hibernators. Although body temperatures are only slightly lower, heart rates are greatly reduced. In addition, unlike many small mammal hibernators, bears do not have to eat or eliminate waste, but subsist entirely on their stored fat. However, black bears are not true hibernators, and most bears can be aroused if prodded sufficiently. If the weather becomes exceptionally warm some bears may wake up and wander around for short periods during the winter months.

With the coming of spring and warmer weather, bears emerge from their dens and search for food. During the winter they may have lost up to 30 % of their predenning weight. Most bears continue to lose weight during the early summer period until mid-July when quantities of berries start to become available.

Travel and feeding habits

Black bears are capable of travelling great distances biologists who have live trapped bears and removed them 80 km or more from their home ranges have sometimes been surprised by the bears' return. The home ranges of females are usually quite restricted. Ranges of adult males encompass several female ranges. Like most animals, they have customary routes of travel, which they regularly follow as they move from one area to another. Old time bear hunters took advantage of this and frequently set their traps along these well used trails.

The activity pattern of black bears varies from area to area depending on a number of factors, including human activities. In wilderness areas they are usually most active from dawn until dark, whereas bears in areas with high human activity may be mainly nocturnal to avoid contact with people. Of course, some individuals solicit human contact in hopes of obtaining a free meal.

Black bears are omnivorous and will eat almost anything available. Most of their food is vegetation, especially in the late summer and autumn when berries and nuts are available. Favourite fruits include blueberries, buffalo berries, strawberries, elderberries, saskatoons, black cherries, and apples. Acorns, hazelnuts, and beechnuts are other preferred foods. Insects such as ants and grasshoppers rate high, and black bears will overturn logs, old stumps, and stones while foraging.

Fish, small mammals, and occasionally birds are also on the black bear's menu. In the spring some bears may prey upon newborn moose calves, deer fawns, caribou calves, or elk calves. Carrion of any sort is highly prized and its attractiveness to a bear increases with its degree of decomposition. Of course a tree containing honey is always a treat. Bears drink frequently and are usually found in the vicinity of water.

Causes of death

Recently, the increasing demand for bear gall bladders, bear paws, and other parts that are believed to have medicinal and aphrodisiacal value has caused concern about increased illegal killing of bears. In certain parts of the world a dried gall from a wild bear may sell for up to $50 000.

Some black bears harbour parasites such as tapeworms and roundworms, but these seem to have little effect on the bear's health. In general, wild black bears have remarkably few internal or external parasites. From a public health viewpoint, trichinosis, which is caused by a nematode or roundworm, is probably the most important parasite of bears. As people can become infected, all bear meat should be cooked carefully before consumption.

Bear trees

Biologists think that trees repeatedly clawed and marked by bears
serve as a form of communication.
Adult males use these trees most frequently, presumably to advertise
their presence to potential mates or potential rivals.
Most markings are done during the breeding season in late spring
or early summer (from mid-June to mid-July).

Relationship to people

The attitude of people towards bears has always been one of caution, respect, and, in primitive times, even reverence. Many Amerindians have special veneration for the bear, and any hunter who kills a bear commands considerable respect.

In the early days of European settlement, bear hunters made their living hunting and trapping bears, wolves, and cougars because of their presumed danger to livestock and perhaps people. In fact, most black bears kill few large mammals and can not be classified as predators in the same manner as wolves, weasels, or polar bears. They are now prized as game animals, because they are large and elusive and test the skills of hunters and because bear meat if properly prepared is considered highly palatable by many fanciers of wild game.

At this time in Canada and Alaska there are two legal hunting seasons for black bears, spring and fall; however, most jurisdictions in the lower 48 states no longer allow bear hunting in spring because of overharvest.

Black bears are extremely fond of garbage and frequently congregate at dumps. This habit occasionally leads them into contact with people who enjoy observing the feeding antics of the bears, especially the younger ones. Of course, if the bears demolish some picnicker's lunch, this feeding behaviour is not thought so amusing.

Most bears are extremely shy and retiring and usually avoid direct contact with humans. Incidents of black bears attacking humans have been reported but are extremely rare. These attacks were usually made by bears that had been feeding on garbage or by animals in extremely poor physical condition due to old age, disease, or wounds.

Occasionally bears cause trouble when they prey on livestock or upset beehives in an apiary. Usually incidents of this type are caused by one or two individuals and the problem is solved by their removal.

When people watch bears in the wild they should never forget that these are wild animals that must be treated with caution. They should not be fed. Most bears will hastily retreat if a person approaches too closely, but one should not take unnecessary chances, as bears, like people, are sometimes unpredictable. They are interesting to observe and photograph, but they can be dangerous at close quarters.

In 1992, to limit illegal killing of black bears and international trafficking in gall bladders from wild bears (including endangered Asian bears), the 115 countries (including Canada) that were Parties to the Convention on International Trade in Endangered Species (CITES) voted to list the black bear on Appendix II to the Convention. Since that date, a hunter wishing to transport any part of a black bear through customs of any country that is a member of CITES has had to obtain a CITES export permit from the exporting country.

Reading list

• Banfield, A.W.F. 1974. The mammals of Canada. University of Toronto Press. Toronto.
• Burk, D., editor. 1979. The black bear in modern North America. The Amwell Press. Clinton, N.J.
• Fair, J. 1990. The great American bear. Northword Press Inc. Minocqua, Wisconsin.
• Herrero, S. 1985. Bear attacks. Winchester Press. Piscataway, N.J.
• Kolenosky, G.B. and S.M. Strathearn. 1987. Black bear. Pages 443 454 in Wild Furbearer Management and Conservation in North America. Ontario Trappers Association. North Bay.

	Canadian Wildlife Service - Hinterland Who's Who series Reproduced with permission of the Minister of Public Works and Government Services Canada, 1999. Copyright © 1999 Environment Canada. All rights reserved. Last update: 19 January 1999