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American Black Bear
Ursus Americanus

Copyright(C) 2003 Lark & Laura Ritchie. All Right Reserved

Black Bears - Physical Features

The American Black Bear's name can give misleading information about it's physical appearance. The majority of eastern black bears are black, sometimes with a white "v" patch on the throat and other markings on the chest, but many of the bears in the west are more likely to be brown and coastal areas of Alaska and Canada have bears whose coats are tinged with blue.

Despite their name, black bears' fur can range from white, cream, beige, cinnamon, chocolate, brown, smoky-gray and blue-black to black. In fact, cinnamon, brown and black bears can even be born within the same litter of cubs. The fuzzy, insulating hairs on the bear's undercoat are between 1.25 and 1.5 inches in length and the longer, black guard hairs grow to be 3 to 4 inches long.

The black bear is an omnivore that wanders in search of food. It has a life span of 20 years in the wild, but can live up to 40 years in a zoo. The black bear has forty-two teeth - the carnassial teeth for the shearing of meat near the front and the postcarnassials which have developed into flat-crowned crushing and grinding, molar-like teeth.

They are large, heavy animals with the boars weighing from 150 lbs to 400 lbs and exceptional records of over 600 lbs. A grown male bear stands 2.5 to 3 feet at the shoulder. Sows are much smaller and they do not usually exceed 150 lbs. These bears are usually around 5 or 6 feet from nose to tail in length, with a horizontal shoulder to rump line. Black bears have four powerful limbs and, like humans, have the ability to rotate their forearms, allowing them greater agility in seizing and holding prey. Each of the bear's feet have strong, non-retractable claws that are short and curved. The bear uses these for tearing, digging, climbing and occasionally, for fighting off other bears and animals.

These animals walk flat on the soles of their feet rather than on their toes like many other animals. This and their great size gives them a shuffling gait, but contrary to popular belief bears are not slow and clumsy. This is shown by the skill with they scale tall trees and how they can reach speeds of up to 30 miles per hour. Bears are also great swimmers and are able to swim miles without a rest. Their average swimming speed is 3 to 5 miles an hour and they walk at an average speed of 3 miles per hour.

The black bear has round, erect ears, a short tail and small, brown eyes that are situated on the front of the head. Bears are colorblind and they have poor vision because of the fact that usually live in fairly dense forests. Due to the conditions of their habitat, their senses of hearing and smell have adapted to become keener. Some bears are able to smell a dead animal from 20 miles away.

Black Bears - Location/Range

The black bear occupies most of North America from the Mexican plateau to the Arctic treeline in Alaska and Labrador. In Canada the black bear can be located in coniferous, deciduous and mixed forested areas from Newfoundland to British Columbia and can also be found in swamp lands and berry patches, depending on the season.

Black Bears - Habitat/Environment

Black bears range through many different physical landscapes, as long as they have vegetative cover and will roam up to 150 square miles across the land, looking for food. In the winter, bears prefer to be in swampy or coniferous forests because there is a greater chance of finding shelter for the winter. In the spring, bears move towards more deciduous forests and feed off of the leaves that are there and in the late summer and autumn, they will stay closer to pine forests where berry patches can be found.


Typical Spring Bear Habitat

Because the areas that they inhabit are usually close to human populations, they have lost their fear of man and sometimes, when they let their curiosity take over, they can become a nuisance to farmers and tourists.

The black bear makes it's winter den in hollowed out trees, caves or large depressions in the ground. Other than during the winter, bears do not have a permanent bed and will sleep in leaf filled depressions along their ranging routes.

Black Bears - Reproduction

Depending on geographic location Black bears reach maturity between 3.5 years and 7 years of age. They are usually solitary animals, but will pair off at mating time. Copulation is similar to that of dogs and will last from 15 to 30 minutes. Mating occurs several times over a two to three week period, the male and female remaining together for up to a month during this time, before parting and going their separate ways.

Black Bears mate in early July until early August and fertilization will occur, but the embryo's development will be delayed until well into the autumn or early winter months. This is because of a survival mechanism known as delayed implantation. Delayed implantation allows the ovum to become fertilized at any time during the bears' mating season. One Ontario Ministry of Natural Resources biologist, George Kolenosky, figures that this is nature's way of waiting to see if the sow will find enough food to support herself and cubs through the winter.

The number of cubs largely depends on the amount of food that the mother can find during the fall. If she does not store a sufficient amount of fat, she will emerge in the spring alone. The more food that she consumes in the autumn, the more cubs she will give birth to.

The fertilized ovum will remain in a free floating stage until it finally implants itself into the uterine lining around November or early December. Once implantation has taken place, the gestation period is between six to eight weeks. Because of their brief gestation period the cubs are born small, weighing less than one pound each. The cubs are born in January or February and there can be up to four in a litter, with the average number being two.

A new cub is pink and hairless, weighing 10 to 12 ounces. It's thin eyelids are still closed and will remain that way until the cub is about 40 days old. The baby bear will use it's sense of smell to find it's mother's breast and will be fed exclusively on high fat and protein rich milk several times a day, for the next two months of it's life. During this time the cub will grow black downy fur, teeth and will open it's eyelids for the first time. The baby and it's mother will sleep until early spring when they emerge from their cave or other similar shelter. The cub will be about two months and will weigh approximately 20 lbs upon exiting the winter den.

Black Bears - Feeding Patterns and Relationships

Upon emerging from the den in early spring, the bear will be slow to eat and it will continue to lose weight for the next two to three months. The first things that the bear will consume are new grasses and sedges, with some ants and other insects for protein. It will take a few more weeks before it's digestive system is ready to digest meats and until then their diet will consist mainly of leaves. The fact that they continue to lose weight is connected with their bodies' inability to break down the leaves. Some researchers believe that the leaves just act as filler until more nutritious foods become available.

The black bear starts to gain weight by mid-July and will consume many strawberries, pin cherries, service berries and blueberries. A little later in the season the bears will eat an increasingly larger amount of insects, including ants, bees, wasps and caterpillars. In Autumn, Mountain Ash berries become a part of their diet. The picture below shows bear scat, primarily of Mountain Ash berries.

This closeup shows that this bear was feeing almost exclusively on Mountain Ash.

Bears will eat larger mammals when the opportunity is there, but instances of the bear actually killing another mammal are very rare. The meat that it usually eats is carrion left behind by other predators such as the wolf. Although some people believe that the bear is attracted to the smell of rotting meat, it actually prefers fresher kills and when happening upon an animal carcass, will sometimes eat only the freshest parts.

While 75% of the bears' diet is made up of vegetable matter, the other 25% comes from smaller mammals such as squirrels, birds and their eggs, insects and amphibians. The majority of their protein intake comes from insects; bears will use their claws to dig out ant hills and to break open hornets' nests. They are also great fishermen and climbers, using their skill to get fish from rivers and honey from wild bees nests.

Bears have no permanent bed and will wander for miles in search of food. Along the way they will stop for the night at various locations. The males will wander much further than a sow and her cubs and a boar's territory can overlap the territories of many females. With both sexes however, they will remain closer to their homes if the food supply is plentiful. In poor berry production years, Ontario Bear biologist, Martin Obbard, has radio collared bears, and found them up to 160 kilometers from the original collaring location.

Bears have an excellent homing mechanism as shown with one black bear in Michigan. It was brought, by air, 150 miles from it's home territory and found it's way back in less than two months. One brown bear in Alaska was moved to an island in Prince William Sound which was 58 miles away. Two months later, the bear was found dead only 100 meters from where it had been originally captured. To return to that spot, the bear had to swim 7 miles to one island, a half mile to another island and then 2 miles to the mainland, all against freezing water with strong currents.

Near the end of the summer bears begin eating larger amounts of food that has higher levels of fat, nutrients and protein. Before they den up for the winter, male bears can gain up to two pounds per day. This huge weight gain is important so that they will have enough fat to live of off during the winter. It is especially important for the females because it will influence the number of cubs that she will give birth to. This is nature's way of preventing starving. If there is not enough food, no more new cubs will be produced.

Black Bears - Adaptations For Survival

To survive the harsh northern winters, black bears have many adaptations. The bear grows two different layers of fur. The under layer of fur is shorter and fuzzier and is there to insulate during the colder seasons. The outer layer of fur or "guard hairs" are glossy black and grow much longer than the inner layer. This system allows warmed air to be trapped in between and prevents heat loss. The bear's winter coats are shed in the spring.

During the late summer and early autumn black bears gorge themselves on food. They do this to gain an extra layer of fat to help in insulating and so that their bodies will have nutrients during the winter. As the weather gets colder, the black bear will begin to prepare a shelter for the winter. The shelter can be a cave, a hollowed out tree or any other similar space. The bear will line the bottom of it's den with grasses and leaves to lie on while it sleeps. Leaves and other vegetation is raked from several yards around the den to provide both insulation, and a comfortable bed for the winter.

As far as the true definition of hibernation goes, black bears do not hibernate. During hibernation, the body temperature drops and the metabolism slows. In the winter bears will go to sleep and their heart rates will slow. Their breathing rate will also drop to 5 or 6 breaths per minute. In this state, bears can sleep for extended periods of time and are capable of remaining in the same position for up to one month, but will awaken easily if disturbed. If the bear has not consumed enough food to last the winter, if it is an unusually warm day or if it finds it's den uncomfortable, the bear will get up to eat or find another shelter.

On common misconception about "hibernating" bears is that they do not excrete bodily waste during the time that they are sleeping. Some people believe that the bear will consume indigestible foods before denning up to create a fecal plug. This is not true and even though they do not eat, they live off of stored fat and do excrete some bodily wastes.

During the winter, black bears shed their foot pads and grow new ones. This was not known by researchers until recently, but some of the native tribes appear to have had past knowledge about this. Scientists are not sure why bears do this, but it is probably the reason that they seem reluctant to venture far from their dens. Their new foot pads are still too tender for long journeys.

Because they live in dense forests, black bears are sometimes thought to have relatively poor eyesight.However, their sense of smell and hearing seem to bevery sharp. To become aware of whatever dangers are around, bears will stand up on their hind legs and sniff the air. This allows them to both see and smell predators well before they meet face to face and helps them to find food as well.

Cubs are very frisky and are sometimes hard for the mother to control, but they are born knowing that when their mother gives them a warning growl, it is time to be quiet. Coyotes and adult male bears are real threats to a baby bear and some studies have reported that as many as 40% of new cubs are killed by adult boars. When the mother growls, the cub will scamper up a tree and out onto the thinnest branch that will support it's weight. There it will remain until it is told to come down by it's mother. In the tree, the cub will be safe because the thin branch is not enough to support the weight of any larger predator.

In the summer, bears roam in a very definite pattern searching for food. The bears will mark these territories by urinating, defecating and by biting and clawing at trees. These claw marks are a good indicator to other bears about the bear who made them because they reach up as up as high as they can to make these claw and bite marks.

The following photo shows a bear marking, made by scratching a balsam fir, in northern Ontario.

Some male bears have ranges up to 150 square miles from their home territory and females up to 50 square miles. On bear in Pennsylvania was tracked in an area ranging to 380 square miles. In either case, if there is an abundance of food, they won't roam as far.

When bears fear a conflict they will lower their heads, extend their lips, chop their teeth and emit a low moan. This is usually a warning to the challenger. They will also 'blow' pursing their lips, and expelling air, or 'woof' and snort. Bears are not usually aggressive animals and they will only attack if they feel threatened or are injured. However, Black Bears do threaten, and sometimes charge towards another bear, or person to protect a food source. A mother bear can become fierce with the birth of her cubs and may attack if she feels that their safety is being threatened. One study in the Great Smoky Mountains National Park recorded 624 aggressive acts toward humans, but only 6% (37) actually ended in contact.

Black Bears - How Black Bears Can Harm Humans

Black bears are considered a nuisance when they forage around garbage dumps and campsites. They enter into our parks and communities because they have learned that these places are an easy source of food. Bears also have the reputation of raiding farms and eating their crops, especially corn and oats. Bears begging for food in tourist parks have lost all fears of humans and this is when they can become dangerous. In the wild, bears are afraid of men and will usually retreat without confrontation, but nuisance bears do not fear humans, and sometimes, will not retreat. Unless the person has a rifle, the bear will likely win any contacts. Other than in these situations, or when the bear is injured or protecting cubs, the incidences of bears attacking humans have been fairly low.

Black bears can damage trees in the forest by clawing and biting to mark their territory. One study found that in a certain area, 30% of the trees had been damaged by the black bear.

Black Bears - Human Abuses

In the early 1900's many bears became part of traveling circus acts because they were easy to tame and could be taught to do tricks. However, in many cases these animals were mistreated and not given proper care. Now there are regulations governing their care to ensure against abuse, but even some zoos have standards that do not meet regulations for the proper and healthy treatment of these animals.

As with any other animal in the wild, the strain that we are placing on the environment has a direct impact on the bear. Polluting of the air and water by our huge factories and manufacturing plants destroys the animals home, food and can affect it's health. Deforestation cuts down many trees and reduces the areas that these animals can inhabit. Even when the trees are replanted, it will take at least 50 years for the forest to return to normal. Fires caused by careless campers also destroy acres of a bears territory and many animals can be killed in an out of control blaze.

Overhunting and poaching is another serious threat to the bear population. Although the black bear is not yet in danger of becoming extinct, many of the other species of bears around the world are. Studies done by Ontario naturalists have determined the amount of bears that can be harvested in different population sizes and other measures are being taken to ensure that the black bear does not become in danger of extinction.

Black Bears - Other Interesting Information

Bears are great climbers despite their size and appearance. Diminishing amounts of chestnuts in the United States helped to prove this. At one time black Bears living in the States consumed large amounts of chestnuts. When there was a shortage of chestnuts, these bears were forced to turn to acorns as a substitute. Their skill in scaling the tall oak trees dispelled the myth that they were clumsy animals.

The Teddy Bear is named after American president Theodore Roosevelt. On a hunting trip he refused to shoot a cub that crossed his path and was made fun of. A toy maker, Morris Michtom, created the first stuffed bear and got permission to use the president's nickname.

Bears are not born blind. When the cubs are born their eyelids are still closed and they do not open until the cub is 40 days old. That has led to the belief that bear cubs are born without the ability to see.

Bears are not the thinnest after coming out of their dens. Although the bears have lost 15 to 20% of their autumn weight by spring, they will usually continue to lose weight for the next two or three months, until berry crops provide rich food sources.

The bear prefers fresh meat to rotten meat, but will eat kill that isn't too old. If it approaches an animal that has been dead for awhile, the bear would eat only the freshest parts and leave the rest behind.

North American Indian hunters apologize to the bear after killing it, give it a long list of needs to justify it's death and then perform a complicated ritual to release it's spirit.

Inuit bear hunters have a touching ritual that they perform after killing a polar bear. They will take snow and melt it in their mouths and then drip it into the polar bear's jaws. This is to quench the bear's legendary thirst.

West Coast Indians have legends about "ghost bears". These legends are based on the Kermode bear, a sub-species of black bear. It's fur is white or yellowish-white.