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American black bear

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American Black Bear
Scientific classification
Kingdom:
Animalia
Phylum:
Chordata
Class:
Mammalia
Order:
Carnivora
Family:
Ursidae
Genus:
Ursus
Species:
americanus
Binomial name
Ursus americanus
Pallas, 1780
Black Bear redirects here. For the Eurasian Black Bear, see Asiatic 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 40 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 culls. By current estimates, more than 800,000 are living today on the continent [1].

Physical description

The American Black Bear is about 1.8 m (6 feet) long. Females weigh between 40 and 180 kg (90 and 400 pounds); males weigh between 68 and 225 kg (150 and 500 pounds). Cubs usually weigh 200 to 450 g (between seven ounces and one 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 depending on the subspecies, 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). Further adding to the confusion, they occasionally have a slight white chest blaze on either side of the river.

Although they are able to stand and walk on their hind legs, they usually stand or walk on all four legs; when they do stand, it is usually to get a better scent or look at something. Their characteristic shuffling gait results from walking flat-footed (called plantigrade), with the hind legs slightly longer than the front legs. 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 strong claws used for tearing, digging, and climbing. One blow from a powerful front paw can kill an adult elk.

Habitat and behavior

Black Bear Pocosin Lakes National Wildlife Refuge
American Black Bear track, Hemingway, SC

They prefer forested and shrubby areas, but use wet meadows, high tidelands, ridgetops, burned areas, riparian areas, agricultural fields, and avalanche chutes. They also frequent swampy hardwood and conifer forests. Black bears sometimes hibernate during winter and may build dens in tree cavities, under logs or rocks, in banks, caves, or culverts, and in shallow depressions. After emerging from their winter dens in spring, they seek carion 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 as travel corridors.

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 (delayed implantation), 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 has 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 (heat) again.

Cub survival is totally dependent on the skill of the mother in teaching her cubs what to eat, where and how to forage (find food), where to den, and when and where to seek shelter from heat or danger.

American Black Bears are omnivores. They eat a wide variety of foods, relying most heavily on grasses, herbs, fruits, and mast. They also feed on carrion and insects (mainly for the larvae) such as carpenter ants (Campanotus spp.), yellow jackets (Vespula spp.), bees (Apidae), and termites (Isoptera), and raid bee's nests for honey.

They sometimes kill and eat small rodents and ungulate fawns. Like the Brown Bear, they readily eat dead creatures (carrion). Like many animals, they seldom attack unless cornered or threatened, or wounded. They are less likely to attack humans than grizzly bears and typically have long since run for cover before one catches sight of them. Grizzly attacks are most often defensive, while black bear attacks on humans, although extremely rare, are often predatory. This makes feigning death when a black bear attacks ineffective. It is estimated that there have been only 56 documented killings of humans by black bears in North America in the past 100 years.

Black bears eat a great variety of vegetation and nuts, as shown in the list below. The list reflects the different types of habitat in which it is found, from prairie to swamps to both eastern and western types of forest.

File:American Black Bear cubs.jpg
American black bear cubs
Close-up

They will also eat salmon (Oncorynchus spp., Salmo salar), suckers, alligator eggs, crayfish, and trout and will raid orchards, beehives, and agricultural crops. They may frequent garbage dumps or may raid the trash bins of businesses or private homes. Black bears may occasionally prey on domestic sheep and pigs when their natural foods are scarce.

Predators include other black bears, man, and the Grizzly Bear (Ursus arctos horriblis). Coyotes (Canis latrans) and Cougars (Puma concolor) may prey on cubs. Traffic is also a major cause of mortality; in Florida alone, more than 100 bears are killed on roads each year.

Taxonomy and subspecies ranges

The American Black Bear is classified in the class Mammalia, order Carnivora and family Ursidae. Currently accepted subspecies (with their respective ranges) include:

Ursus americanus altifrontalis the Pacific Northwest coast from central British Columbia through northern California and inland to the tip of northern Idaho and British Columbia
Ursus americanus amblyceps Colorado, New Mexico, west Texas and the eastern half of Arizona into northern Mexico; southeastern Utah
Ursus americanus americanus from eastern Montana to the Atlantic; from Alaska south and east through Canada to the Atlantic and south to Texas
Ursus americanus californiensis the Central Valley of California, north through southern Oregon
Ursus americanus carlottae Queen Charlotte Islands and Alaska
Ursus americanus cinnamomum Idaho, western Montana, and Wyoming, eastern Washington and Oregon, northeastern Utah
Ursus americanus emmonsii southeastern Alaska
Ursus americanus eremicus northeastern Mexico
Ursus americanus floridanus Florida, southern Georgia and Alabama
Ursus americanus hamiltoni the island of Newfoundland
Ursus americanus kermodei the central coast of British Columbia
Ursus americanus luteolus eastern Texas, Louisiana, southern Mississippi
Ursus americanus machetes north-central Mexico
Ursus americanus perniger Kenai Peninsula, Alaska
Ursus americanus pugnax Alexander Archipelago, Alaska
Ursus americanus vancouveri Vancouver Island, British Columbia

History and controversy

File:American-black bear.JPG
This is a Black Bear from Woburn Safari Park
Irish Guards, wearing bearskins
A white individual (stuffed), Rothschild Museum, Tring

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. 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, bears were quite uncommon before the modern era because 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 population increases in neighboring Pennsylvania and New York, that number increased to nearly 1500 by 2003. The result is that the residents of this densely populous state sometimes awaken to find the garbage ripped to shreds or a bird feeder knocked to the ground at best, and at worst a bear invading the home or attacking. Invasion usually happens after a bear has lost its fear and has come to associate people with food, and attacks occur when a human gets in the way of the food. This is a cause for concern among civilians and scientists alike. Similar events have unfolded in other states and in Canada. 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.

Captive black bears at a zoo in Florida

Today, a major threat to the American black bear is poaching, or illegal killing, to supply Asian markets with bear galls 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.

Black bears are abundant in much of the West, in portions of the Midwest, and in most of Canada. For example, Ontario is home to about 100,000 bears, with at least as many in neighboring Quebec, while Minnesota has a very healthy population of 30,000 bears. In contrast, Iowa, where land is heavily used for agriculture, has virtually none. Most eastern populations in the United States are seeing a marked, steady increase in population: bears are moving back into places where they may not have been present for over a century as suitable habitat has come back. In eastern states with heavily wooded areas, populations are growing very quickly; in North Carolina there were 11,000 bears at last count in 2004, Pennsylvania estimates 15,000 bears currently, New Jersey (one of the urbanized states) 1,500, 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 & Wildlfie 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. Numbers of bears in the Louisiana subspecies continue to be at critically low levels, although several 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.

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.

Encountering a black bear in the wild

If one encounters a black bear in the wild, it must be given plenty of room; try to avoid any contact by slowly backing away and leaving the area. If a black bear charges at you, it is most likely a "bluff charge" where the bear "stops short". Bluff charges are designed to frighten you off or to assert dominance; stand your ground and do your best to appear imposing. Huddle together if in a group, raise your hands or backpack in the air to appear larger, and make plenty of noise. Unless you have come between a sow and her cubs (or you are simply unlucky), you will probably succeed in scaring it away. Avoid eye contact with the bear, but after it has engaged you, seek eye contact to discourage the animal. A bear that rears up on its hind legs is not signalling aggression; a black bear's range of view is a meter (three feet) off the ground, whereas a human's is between 1.5 and 2 m (five to six feet). It is trying to get a look at what you are and see whether you are a threat. If you hear the bear making a popping sound with its jaw, it is warning you that it is uncomfortable. That is a sign to slowly back away (if possible) and leave the area. Headlong flight must be avoided at all cost because the bear will pursue as prey and bears can achieve sustained speeds of up to 48 km/h (30 miles per hour).

If the bear charges and doesn't "stop short" but makes actual physical contact with you, you must fight back. Use whatever you have close at hand to try to injure it so that it no longer finds you worth the fight. In particular, aim for the nose, as it is a sensitive part of the bear, or the face in general. The bear's thick skull makes blows to the top and side of the head nearly useless. It is not uncommon for black bears to disengage after being injured; pepper spray in the eyes has been known to work, but one needs to be fairly close to the bear to hit the eyes with the spray. If fighting the bear does not seem like a wise choice, consider other options. If you play dead, grizzlies may leave you alone, but black bears will begin to eat you or drag you away. You cannot outrun a black bear. Climbing a tree is futile, since black bears excel at climbing trees. Retreat is usually the best option, but your retreat must be slow and methodical, backing away from the bear. 

    ►  The rules applicable to brown bear encounters 
       are not the same as those applicable to black 
       bear encounters. Brown bears are more likely to 
       make repeated bluff charges and conduct knock-
       down attacks to defend cubs or a kill. They 
       may also smack the ground, bark and clack their 
       teeth together as part of a defensive posturing 
       to keep humans and other animals at bay. Brown 
       Sows are far more likely to defend their cubs 
       with force, way beyond a slashing attack to the 
       eyes and face. People have weathered brown bear 
       attacks (including Grizzly attacks) by dropping
       into a "fetal" position with neck and face 
       between the knees with your hands over the back 
       of your neck, or by lying flat on the ground on 
       your stomach with hands link behind your neck.

Black bears are much less likely to engage in the kind of defensive behavior associated with brown bears. In most cases of rare black bear attack, the bears exhibited classic predatory behavior. They will not bark, clack teeth, or make noise. Rather, they will simply approach at a measured pace and attack the human as prey. The calm appearance of the black bear may have lured some victims into a false sense of security. A black bear calmly and steadily approaching that is not bothered by yelling or thrown objects should be considered extremely dangerous. Because black bear are much less likely to be conducting a purely defensive attack, "playing dead" is never an appropriate response with them.

In areas where carrying a firearm is allowed, that is the time to use one. A rifle in the .30-30 class or better firing expanding bullets of 150 grain or greater is considered the minimum for black bear, though 180 grain bullets from a rifle in the .308 (7.62x51mm) class may be a safer bet. A .357 magnum, 10mm Auto or .44 magnum handgun firing heavy hardcast lead slugs is potentially effective but requires more skill to deploy effectively than a rifle. A shotgun loaded with hardcast Brenneke slugs is also a popular option.

In summary, the game plan in any encounter is, quite simply:

  • retreat noisily and slowly, if at all possible, without appearing weak,
  • fight if the bear knocks you down or otherwise makes contact with you.

Predation by grizzlies or black bears is an exceedingly rare event and mostly the result of extremely hungry, younger individuals forced near human habitation as a result of territorial pressure.

Attacks by bears are in most cases defensive measures and occur when the animal is startled by human presence or, in the case of brown bears, when a human comes too close to offspring or wanders in between the sow and her cubs. Some people have taken to hand-feeding half-tame bears and have been bitten or swatted. The explanation for this kind of behavior is that the bear is attracted close to the human by the food, but once the food is gone, the animal will feel highly insecure so near a human, and instead of taking flight by turning its vulnerable back, it will first move to disable the human. Usually the bear will swat the human just hard enough to cause the human to lose balance and then turn around and run away. Behavior researchers studying bear behavior assume that bears view human beings as bears, meaning they expect humans to behave like bears and signal accordingly. When associating with one another, bears use light swats and measured bites that do not break the skin or merely scratch to communicate displeasure with another individual's behavior. Bears learn as cubs how to control the strength of their bite in social play. People in wildlife parks who have taunted bears by miming to offer them food when in fact they had none to offer, or people who tried to pet the bears, were given light, yet painful signal bites and nips as the animals communicated their displeasure. In most cases when bears have bitten or swatted humans, the injuries they caused were nowhere near the animals' potential of inflicting injuries, showing that the bears as social animals usually practice great restraint and avoid unnecessary deaths.

Great care must be taken to properly identify a bear as either a black bear or a grizzly, as it is not enough to rely on the color of their fur. There are many grizzlies with very dark fur and black bears with cinnamon or completely brown fur. The main differences to look for are the ears (black bears have very large ears in comparison with grizzlies) for the grizzly, a hump on its back; the claws (black bears have short claws for climbing, grizzlies have longer claws for holding onto prey and digging); and, above all, the face. A black bear has an elongated snout, whereas a grizzly has a flat, dishlike facial appearance.

Camping

When camping, it is wise to take steps to avoid negative encounters with bears:

  • Do not bring food into the tent. It invites more than just ants into your bedroom.
  • Clean all pots, pans, and grills thoroughly with unscented soap and water, making sure no trace of food is left for animals to smell.
  • Do not leave food lying around. Clean up everything right away after a meal and contain uneaten food in plastic bags or containers.
  • Do not assume food and supplies are safe in a car. If you must keep supplies in a car, lock them in the trunk. It is not unknown for bears to try to break into cars through the windshield or windows!
  • Do not go to bed in the same clothes you were cooking in. Keep dirty clothes and packs outside the tent.
  • If possible, use a bear canister to keep foods safe or hoist your food in a tree ten feet off the ground and four feet out in a bear bag.
  • Be careful about how you dispose of garbage. Try to dispose of garbage at a designated facility away from the campsite.
  • Try not to bring any sweet-smelling items with you, like scented soap or cough syrup. (Bears can't read the label, and they assume it is food.) If you must bring it at all, hoist it up in a tree in a bear bag or bear canister. Try not to wear anything with a scent, including deodorant and insect repellant, after 4 p.m.
  • If the bear gets to the food anyway, do not attempt to get it back. It is not worth the fight.
  • Do not feed a bear or attempt to do so. (What would you do if the bear found out you don't have any more?)
  • If you have brought a pet with you, make sure it is secured and on leash at all times.

Miscellaneous

  • There has been considerable evidence of black bear activity that seems to suggest that the population may be extending its range back into historical territories in Ohio, Kentucky, Pennsylvania, and other areas where bear were eradicated and have not been present for a considerable amount of time. It is suspected that adolescent males seeking new territory are wandering far and wide, literally hundreds of miles, by following natural and manmade corridors (rivers and highways) back into their ancestral lands. It has generally been recent policy that if the animal does not become a nuisance, is not a danger, or is not in any imminent peril, that it be allowed to exist unmolested and without hindrance. Most cases remain out of the general public's knowledge until there has been a significant human-bear encounter. [2]
  • The sports teams of the University of Maine are known as Black Bears; it is also the mascot for Baylor University who maintains two bears on campus.
  • Ursus americanus kermodei, commonly known as the spirit bear, is a rare white (not albino) subspecies found in temperate rain forests on the Pacific coast of North America. Native tradition credits these animals with supernatural powers.
  • Smokey Bear, mascot of the United States Forest Service is based on an actual black bear cub found in New Mexico after a forest fire.
  • In August 2004, several news media outlets[3] reported that a wild black bear was found passed out after drinking about 36 cans of beer in Baker Lake, Washington, USA. The bear opened a camper's cooler and used its claws and teeth to puncture the cans. It was found the bear selectively opened cans of Rainier Beer and left all Busch beer unconsumed.
  • The largest Black Bear on record was in North Carolina in 1999 and was weighed at 400 kg (880 pounds). It was reported to have been eating hogs from an industrial hog farm.
  • Winnie the Pooh was inspired by an orphaned black bear cub from the Canadian city of White River, Ontario. During World War I, the bear was adopted by (then) Lieutenant Harry Colebourn, a member of the Royal Winnipeg Rifles of the Canadian Infantry. It later became the mascot for the company.
  • The Black Bear, a two part 2/4 March, is a famous traditional tune played by Pipe Bands around the world; it is the traditional march for Scottish soldiers returning to barracks at the end of the day. It is traditionally played at the end of each performance of the Edinburgh Tattoo

See also

References

  • Template:IUCN2006
  • "Ursus americanus". Integrated Taxonomic Information System. 18 March. {{cite web}}: Check date values in: |date= and |year= / |date= mismatch (help)
  • Bears, consulting editor Ian Stirling, Fog City Press, 1993.
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