The American Black Bear
The American Black Bear (Ursus americanus) is the
most common bear species native to North America. It lives
throughout much of the continent, from northern Canada and Alaska
south into Mexico, from the Atlantic to the Pacific. This includes
41 of the 50 U.S. states and all Canadian provinces except Prince
Edward Island. Populations in the east-central and 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. It is a close
relative of the Asiatic black bear with which it is thought to share
a European common ancestor.
Conservation Status
The Black Bear is listed under the Lower Risk Category as (LC) Least Concern.
Description
The American Black Bear usually ranges in length from 150 to 180 cm (60 to 72 inches) and typically stands about 80 to 95 cm (34 to 48 inches) at the shoulder. Standing up on its hind feet, a black bear can be up to 7 feet tall. 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 seldom exceed 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 880 lbs (400 kilograms). 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 long.
Although black bears can stand and walk on their hind legs it is more normal for them to walk on all fours. When they do stand, it is usually to get a better scent or to look at something. Their characteristic shuffling gait results from their plantigrade (flat-footed) walk, with the hind legs slightly longer than the forelegs. Another reason for the apparent shuffle is that they commonly walk with a pacing gait. Unlike many quadrupeds, the legs on one side move together instead of alternating, much like a pacer horse. Each paw has five long, strong claws used for tearing, digging, and climbing. When necessary, they can run at speeds up to 30 miles per hour (48 kph) and are able swimmers.
Black Bear Tracks
The tracks of this slightly pigeon-toed creature are characterized by the overlapping of the hind prints onto those of the front. The heel pad of the rear foot is long and vaguely resembles that of a human. Five toes with equally long claws are evenly spaced along the top of this pad.
Straddle: 43
- 47 cm (17.2 - 18.8 in)
Stride: 45 - 50 cm (18 - 20 in)
Tracks: Front - 15 cm (6 in) long / 14 cm (5.6 in) wide
Tracks: Rear - 25 cm (10 in) long / 15 cm (6 in) wide
Behavior
Black bears are found in a wide variety of habitats across their range. They prefer forested and shrubby areas but they are also known to live on ridgetops, in tidelands, burned areas, riparian areas, agricultural fields and, sometimes, avalanche chutes. Black bears can be found from hardwood and conifer swamps to the rather dry sage and pinyon-juniper habitats in the western states. Black bears typically "hibernate" during winter in hollowed-out dens in tree cavities, under logs or rocks, in banks, caves, or culverts, and in shallow depressions. Dens are normally not reused from one year to the next. While they do not eat, drink, defecate, or urinate during hibernation, it is not the true hibernation of smaller mammals since their body temperature does not drop significantly and they remain somewhat alert and active. Females give birth and nurse their young while hibernating.
After emerging from their winter dens in spring, they seek carrion from winter-killed animals and new shoots of many plant species, especially wetland plants. In mountainous areas, they seek southerly slopes at lower elevations for forage and move to northerly and easterly slopes at higher elevations as summer progresses. Black bears use dense cover for hiding and thermal protection, as well as for bedding. They climb trees to escape danger and use forested areas and rivers as travel corridors.
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 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.
The cubs are generally born in January or February. They are very small, about 10-14 ounces, and are blind, nearly hairless, and helpless when born. Two to three cubs are most common, though up to four and even five cubs have been documented. First-time mothers typically have only a single cub. The mother nurses the cubs with rich milk, and by spring thaw, when the bears start leaving their dens, the cubs are fur-balls of energy, inquisitive and playful. By this time they are about 4 to 8 pounds (2-4 kg). When their mother senses danger, she grunts to the cubs to climb high up a tree. They are weaned between July and September of their first year and stay with the mother through the first winter. The cubs become independent during their second summer (when they are 1.5 years old). At this time, the sow goes into estrus again.
Cub survival is totally dependent on the skill
of the mother in teaching her cubs what to eat, where and how to
forage, where to den, and when and where to seek shelter from heat
or danger.
Hunting and 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 for 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 have preyed on white-tailed deer fawns. In addition they have been recorded preying on elk (cervus canadensis) 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 frequent garbage dumps or appropriate food from the trash bins of businesses or private homes.
Black bears often drag their prey to cover, preferring to feed in seclusion and frequently begin feeding on the udder of lactating females, but generally prefer meat from the viscera. The skin of large prey is stripped back and turned inside out with the skeleton usually left largely intact. Unlike wolves and coyotes, black bears rarely scatter the remains of their kills. Vegetation around the carcass is usually matted down by black bears and their droppings are frequently found nearby. Black bears may attempt to cover remains of larger carcasses, though they do not do so with the same frequency as cougars and grizzly bears.
Today, a major threat to the American black bear is poaching, or illegal killing, to supply Asian markets with bear galls, hearts, and paws, considered to have medicinal value in China, Japan, and Korea. The demand for these parts also affects grizzly and polar bears. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), a treaty among more than 120 nations, provides measures to curb illegal trade in wildlife and wildlife products across international boundaries, helping to protect the black bear from poaching. Perpetrators caught poaching or smuggling either item out of the United States or Canada may face very serious legal ramifications, and park rangers within both countries are charged with the protection of the bears under their jurisdictions up to and including arrest.
Black bears are abundant in most of the western states and in most of Canada, but its presence in the Midwest is uneven by comparison. For example, Ontario is home to about 100,000 bears, with at least as many in neighboring Quebec, while the Upper Midwest has a very healthy population with 30,000 bears in Minnesota alone. In contrast, nearby places like Iowa, Kansas and Illinois have virtually none. Many Midwestern states have not had a native breeding population of bears since the turn of the 19th century or earlier and many are still heavily used for agriculture today.
Most populations east of the Mississippi River are seeing a marked, steady increase in population: bears are moving back into places where they typically have been absent for over a century as suitable habitat has returned. In eastern states with heavily wooded areas, populations are growing rapidly; in North Carolina there were 11,000 bears at last count in 2004, Pennsylvania estimates 15,000 bears currently, New Jersey (a heavily urbanized state) estimated 3,529 in 2003, and even tiny Rhode Island has seen evidence of bears moving into areas where they haven't been in decades. The Florida black bear has also seen increases in numbers in recent decades, in 2004 the Florida Fish & Wildlife Commission estimated over 2,400 bears were in the state. Unfortunately, not all is well. Continued development may reduce connectivity between the already separated populations in Florida. The Louisiana subspecies continues to be at critically low levels, although several successful reintroduction projects have added bears to new areas of the state.
In Mexico, the indigenous black bear population is listed as endangered and is mostly limited to increasingly fragmented habitat in the mountainous northern parts of the country. Individuals from this area seem to have naturally recolonized parts of southern Texas and along the Rio Grande.
In 1992, the U.S. Fish and Wildlife Service listed the Louisiana black bear subspecies as "threatened" under the Endangered Species Act, meaning it could be in danger of extinction throughout all or a significant portion of its range in the near future. The American black bear is also protected by legislation in the affected states (Louisiana, Mississippi, and Texas), owing to its close resemblance to this subspecies. The Florida black bear was denied protection under the Endangered Species Act in 1998 and 2004 due to its adequate protection and management by the State of Florida.
Hunting Black Bears is a popular sport, the meat is eaten and often the hides are made into rugs.
Interspecific predatory relationships
In some areas, black bears share their range with the Brown bear. Due to their smaller size, black bears are at a competitive disadvantage against brown bears in open, non-forested areas. Although displacement of black bears by brown bears has been documented, actual interspecific killing of black bears by brown bears has only occasionally been reported. The diurnal black bear's habit of living in heavily forested areas as opposed to the largely nocturnal brown bear's preference for open spaces usually ensures that the two species avoid confrontations in areas where they are sympatric. Black bears are also sympatric with cougars and will sometimes usurp kills from them. Generally, however, black bears prefer not to fight with other predators.
Relationships with Humans
Livestock depredations by black bears occur mostly in spring. Limitations of food sources in early spring and wild berry and nut crop failures during summer months are probably major contributing factors. Black bears can do extensive damage in some areas of the northwestern states by stripping the bark from trees and feeding on the cambium.
Though black bears will attack adult cattle and horses, they seem to prefer sheep, goats, calves and pigs. They normally kill by biting the neck and shoulders, though they may break the neck or back of prey with blows from the paws. Evidence of a bear attack includes claw marks are being frequently found on the neck, back and shoulders of these larger animals. Surplus killing of sheep and goats are relatively common. Bears have been known to frighten livestock herds over cliffs, causing injuries and death to many animals. Whether or not this is intentional is not known.
History and Controversy
Because their behavior has been little understood until recently, black bears have been feared and hated. Before the 20th century, these bears were shot intermittently as vermin, food, and trophies, being seen as either a vicious beast or an endless commodity; until recently, in many areas, bounties were paid for black bears. The Queen of the United Kingdom Foot Guard's hat has been for centuries made of black bear fur, and its original name is bearskin.
Paradoxically, black bears have also been portrayed as harmless and cuddly. For example, the teddy bear owes its existence to a young black bear cub Theodore Roosevelt refused to shoot, and Christopher Milne named his teddy Winnie the Pooh after Winnipeg, a black bear which he and his father often saw at London Zoo. Today, black bears are as much an important game species as they are a point of debate across the continent, especially when it comes to the fact that many are finding life in the suburbs quite comfortable. Given their relatively low reproductive rate, black bear hunting must be carefully controlled and is probably inappropriate in areas where populations are feeble or where habitat is no longer intact.
Their tendencies to follow their stomachs and habitat encroachment by humans have created human-bear conflicts. This is especially true in areas where they may have been uncommon or absent for a long time, as in many parts of the eastern United States. An excellent example is the state of New Jersey. In New Jersey, now the nation's most densely populated state, bears were quite common before the modern era. Because so much land was cleared for homes and farming and as a result of poor policies regarding hunting and forestry; by 1970 only about 100 bears remained. However, because of changes in land use, management, and bear population increases in neighboring Pennsylvania and New York, that number increased to an estimated 3,529 by 2003. The result is that the residents increasingly encounter bears near their homes and workplaces. Education and precaution are needed, especially in areas such as New Jersey where bear encounters are a fairly new phenomena in recent history. Fear of bear attacks is a common concern for these residents. Attacks can happen when a bear has lost its fear of humans and has come to associate people with food. This is a cause for concern among civilians and scientists alike. Similar events have unfolded in other states and in Canada. The rate of contact between black bears in search of food and humans rose to record levels in the western United States in autumn 2007. State, provincial, and federal agencies are working to address the issue with trap-and-release programs, limited hunting, and hazing bears with rubber bullets, other aversion techniques, and dogs. In agricultural areas, electric fences have been very effective.
Taxonomy and subspecies ranges
Ursus americanus amblyceps Native to Colorado, New Mexico, west Texas, the eastern half of Arizona into northern Mexico; southeastern Utah.