Black bear: Difference between revisions

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In addition to plant matter, bears hunt for beehives and eat both honey and bees, as well as ants and numerous varieties of insect larvae. They will also consume bird eggs found in trees. Some black bears are active fishers, but that habit is more common in northwestern salmon streams. In Spring bears sometimes prey on juvenile deer by ambush, dragging prey to cover. They will also take animals shot by hunters if left undisturbed.
In addition to plant matter, bears hunt for beehives and eat both honey and bees, as well as ants and numerous varieties of insect larvae. They will also consume bird eggs found in trees. Some black bears are active fishers, but that habit is more common in northwestern salmon streams. In Spring bears sometimes prey on juvenile deer by ambush, dragging prey to cover. They will also take animals shot by hunters if left undisturbed.


===Interspecific predatory relationships===
Over much of their range, black bears are assured scavengers which, using their large size and considerable strength, can intimidate and, if necessary, dominate other predators in confrontations over carcasses. However, in occasions where they encounter the [[Kodiak bear|Kodiak]] or the [[grizzly bear|grizzly]] bears, the larger two [[brown bear|brown]] [[sub-species]] dominate them. Black bears tend to escape competition from brown bears by being more active in the daytime, and living in more densely forested areas. Violent interactions resulting in the deaths of black bears have been recorded in Yellowstone National Park.<ref>{{cite web|url=http://www.greateryellowstonescience.org/files/pdf/ys5-gunther.pdf |title=Evidence of grizzly bear predation on a black bear in Hayden Valley|author=Gunther, Kerry A. and Biel, Mark J. |format=PDF |accessdate=2011-02-21}}</ref><ref>{{cite web|url=http://www.nps.gov/yell/naturescience/upload/predation.pdf |title=Probable Grizzly Bear Predation On An American Black Bear In Yellowstone National Park|format=PDF |accessdate=2011-02-21}}</ref>


Black bears do compete with [[cougar]]s over carcasses. Like brown bears, they will sometimes steal kills from cougars. One study found that both bear species visited 24% of cougar kills in Yellowstone and [[Glacier National Park (U.S.)|Glacier National Parks]], usurping 10% of carcasses.<ref>{{cite journal |author=COSEWIC. Canadian Wildlife Service |title=Assessment and Update Status Report on the Grizzly Bear (Ursus arctos) |publisher=[[Environment Canada]] |year=2002 |url=http://dsp-psd.pwgsc.gc.ca/Collection/CW69-14-166-2002E.pdf |format=PDF |accessdate=2007-04-08 }}</ref><ref>{{cite journal|title=Encounter Competition between Bears and Cougars: Some Ecological Implications|jstor= 3873109|author=Murphy, Kerry M.; Felzien, Gregory S.; Hornocker, Maurice G. and Ruth, Toni K. |journal=Ursus|volume=10|year=1998|page=55 }}</ref> Fights between the two species are rare, though they can be violent. Cougars occasionally kill adult bears, a behavior reportedly witnessed in the 19th century.<ref name="Finding a Panther Guarding a Dead Bear">{{cite web|title=S. C. Turnbo: Finding a Panther Guarding a Dead Bear|url=http://thelibrary.org/lochist/turnbo/V12/ST363.html|publisher=thelibrary.org}}</ref> There are also 19th and early 20th century records of bears killing cougar, either in defense or in territorial disputes, and occasional fights which ended in both combatants fatally wounded.<ref name="Cougar vs Bears Accounts">{{cite web|title=Cougar vs Bears Accounts|url=http://www.freewebs.com/mountainlionsinfo/cougarvsbearsaccounts.htm|publisher=Everything about the Cougar / Mountain Lion. The Cougar rules wherever it roams|accessdate=2013-06-15}}</ref>
Black bear interactions with [[gray wolf|wolves]] are much rarer than with brown bears, due to differences in habitat preferences. The majority of black bear encounters with wolves occur in the species′ northern range, with no interactions being recorded in Mexico. Despite the black bear being more powerful on a one to one basis, packs of wolves have been recorded to kill black bears on numerous occasions without eating them. Unlike brown bears, black bears frequently lose against wolves in disputes over kills.<ref name="WOLVES">{{cite book | author= Mech, L. David and Boitani, Luigi |title=Wolves: Behaviour, Ecology and Conservation | year=2001 | page= 448 | isbn= 0-226-51696-2 | publisher= University of Chicago Press | location= Chicago }}</ref> Wolf packs typically kill black bears when the large animals are in their hibernation cycle.<ref name="scorzafava"/>
There is at least one record of a black bear killing a [[wolverine]] in a dispute over food in Yellowstone National Park.<ref name="cc">{{cite web|url=http://www.ecoearth.info/shared/reader/welcome.aspx?linkid=22714&keybold=predator%20AND%20%20coyote |title=In Yellowstone, It's a Carnivore Competition| publisher=Washington Post |date=2003-05-19 |accessdate=2011-02-21}}</ref> Black bears may sometimes habitually prey on [[American alligator]] nests. Sometimes, they are fought off by the female alligator but will also occasionally wound or even kill an adult alligator, though neither species are likely to confront a large adult of the other directly.<ref>''Crocodiles: Proceedings of the 6th Working Meeting of the Crocodile Specialist Group of the Species Survival Commission of the International Union for Conservation of Nature and Natural Resources (IUCN publication. New series)''. IUCN (1986), ISBN 2880329051.</ref> Ancedotal cases of alligator predation on bears have been reported, though such cases may involve assaults on cubs.<ref>[http://www.keywestaquarium.com/alligator Key West Florida Attractions | Alligator Exhibit]. Key West Aquarium (2012-11-30). Retrieved on 2012-12-20.</ref>


==Relationships with humans==
==Relationships with humans==

Revision as of 22:56, 16 August 2014

The American black bear (Ursus americanus) is a medium-sized omnivorous bear found in forested areas throughout North America, and the only type of bear native to the Southeast. Its range has been reduced and fragmented by human settlement and populations are most stable in Northern Canada and along the Rocky and Appalachian ranges.

The subspecies Ursus americanus americanus or Eastern black bear predominates in the Eastern half of the continent, while another subspecies, Ursus americanus floridanus or "Florida black bear" is found in southern Alabama and Georgia and Florida.

Black bears became genetically distinct from brown bears and polar bears approximately 5.05 million years ago, in the early part of the Pliocene epoch. American and Asian black bears are more closely related to each other than to other bear species, having diverged approximately 4.08 million years ago. Early specimens displayed larger average size than modern bears, though the fossil record is incomplete. It is believed that the American black bears' flexibility in diet and behavior equipped it to survive where other species died off during disruptions in climate and vegetation. Native Alabamians of the Creek nations called the black bear "nokose", while Cherokee people named it "gv-ni-ge-yo-na." During the settlement of Alabama bears were considered dangerous and were hunted freely.

More than 800,000 bears are thought to survive in the wild, with around half of them in the United States. Though no stable breeding groups are currently known in Alabama, bear populations at the edges of its range are thought to be increasing in recent decades, including a number of sitings in Alabama. A wild black bear, nicknamed "Bruno" was captured in Smithfield in June 1993 and housed temporarily at the Birmingham Zoo before it was released in Tennessee's Cherokee National Forest.


Habitat

Black bears prefer hardwood forests with thick understory and plentiful mast (edible plant materials such as nuts, leaf buds, berries and droops). In the southern Appalachians it is the mixed mesophytic oak-hickory forests that support bear populations.

Physical description

Black bears vary greatly in size and weight depending on age, gender, health and season. Adult males in the Smoky Mountains averaged 250 pounds and females averaged 104 pounds in one study. Exceptionally large individual black bears, weighing more than 1,000 pounds have been reported. Hibernating bears often lose 30 percent of their body weight over winter. They have broad, rounded heads with narrow muzzles and round ears set well back. They have proportionally large paws with black pads and rounded black or dark gray-brown claws. Their tails are vestigial, usually less than 5 inches long.

Their fur is dense and soft. Almost all southern black bears have black fur, though white, blond, cinnamon and a range of brown colors have been found in the species, usually in more arid climates in the West.

Behaviour

Black bears are strong and dexterous. They can lift heavy rocks and operate simple devices such as screw-top and door knobs. They can run at up to 30 miles per hour, swim well, and climb trees readily. Their sense of smell is reportedly seven times greater than a dog's. They have acute senses of hearing and eyesight, and are able to distinguish colors.

Black bears produce a range of sounds, including aggressive growls, snorts bellows and roars as well as a number of mumbles and squeaks expressing apparent contentment in social situations.

American black bears tend to range alone when foraging for food, except when raising cubs or taking advantage of abundant food sources, such as spawning fish or garbage dumps. When several bears feed in the same area, the largest males are dominant and control the best spots.

Bears travel long distances and mark their territories by rubbing their bodies against trees and scratching at the bark with their claws. They are usually nocturnal, especially when close to human settlements.

Bear sows usually produce their first litters of cubs when 3 to 5 years old, though pressures from range reduction sometimes lead them to mate earlier. They usually breed in summer with males seeking several partners during a breeding season. Fertilized eggs are slow to implant and the cubs, 1 to 6 in a litter, are typically born in January and February. Black bear cubs first appear weighing less than a pound and sporiting a downy gray coat and closed eyes. They are born with underdeveloped hindquarters and begin walking after five weeks and are weaned after about 30 weeks. They remain with their mother until reaching 16-18 months and become sexually mature at around three years and reach their full size at around five years.

A black bear's average life span is about 18 years, with individuals reported to reach 31 years in the wild and 44 years in captivity. There are few threats to an adult bear's survival if it has access to an expansive feeding range. Cubs are vulnerable to numerous large predators and juveniles are sometimes killed by brown bears where they share territory. Undernourished individuals are threatened with starvation during hibernation. Most black bear deaths are attributable to human activities such as hunting, trapping and auto-collisions.

Hibernation

Although black bears are genetically adapted for hibernation, many living in warmer climates with longer growing seasons spend less time in metabolic dormancy. Black bears often carve dens out of hollow trees, fallen logs or in cliff banks or caves. Bears in hibernation may occasionally waken to forage, and litters are typically born in the winter months and nurtured in dens until Spring. Florida black bears rarely hibernate unless pregnant.

Diet

Bears forage habitually in the morning and twilight hours for vegetation. In late winter, bears coming out of hibernation will eat whatever they find, including carrion. In spring most of their diet consists of new plant shoots and tree buds. In the summer berries and fruits become more available. As they prepare for winter, bears forage for most of the day to put on weight. Nuts and acorns predominate in the autumn diet, and may be gathered from trees or by raiding squirrel caches. Fall also brings bears farther outside their normal ranges where they may feed on farm crops, human refuse, beehives and bird feeders.

In addition to plant matter, bears hunt for beehives and eat both honey and bees, as well as ants and numerous varieties of insect larvae. They will also consume bird eggs found in trees. Some black bears are active fishers, but that habit is more common in northwestern salmon streams. In Spring bears sometimes prey on juvenile deer by ambush, dragging prey to cover. They will also take animals shot by hunters if left undisturbed.


Relationships with humans

In folklore, mythology and culture

Black bears feature prominently in the stories of some of America's indigenous peoples. One tale tells of how the black bear was a creation of the Great Spirit, while the grizzly was created by the Evil Spirit.<ref>Lippincott, Joshua B. (2009) Folklore and Legends of the North American Indian, Abela Publishing Ltd, ISBN 0-9560584-6-9</ref> In the mythology of the Haida, Tlingit, Tsimshian people of the Northwest Coast, mankind first learned to respect bears when a girl married the son of black bear Chieftain.<ref>Bastian, Dawn Elaine and Mitchell, Judy K. (2004). Handbook of Native American mythology, ABC-CLIO, ISBN 1-85109-533-0</ref> In Kwakiutl mythology, black and brown bears became enemies when Grizzly Bear Woman killed Black Bear Woman for being lazy. Black Bear Woman's children, in turn, killed Grizzly Bear Woman's own cubs.<ref>Averkieva, Julia and Sherman, Mark, Kwakiutl String Figures, UBC Press, 1992, ISBN 0-7748-0432-7</ref> The Navajo believed that the Big Black Bear was chief among the bears of the four directions surrounding Sun's house, and would pray to it in order to be granted its protection during raids.<ref>Clark, LaVerne Harrell (2001). They sang for horses: the impact of the horse on Navajo & Apache folklore, University Press of Colorado, ISBN 0-87081-496-6</ref>

Morris Michtom, the creator of the teddy bear, was inspired to make the toy when he came across a cartoon of Theodore Roosevelt refusing to shoot a black bear cub trapped up a tree.<ref name="LoC">Template:Cite web</ref> Winnie the Pooh was named after Winnipeg, a female black bear cub that lived at London Zoo from 1915 until her death in 1934.<ref name="winnie">A Bear Named Winnie CBC.ca TV (2004)</ref> A black bear cub who in the spring of 1950 was caught in the Capitan Gap fire was made into the living representative of Smokey Bear, the mascot of the United States Forest Service.<ref name="smoke">Template:Cite web</ref>

The American black bear is the mascot of The University of Maine and Baylor University, where the university houses two live black bears on campus.

Sleeping Bear Dunes is named after a Native American legend, where a female bear and her cub swam across Lake Michigan. Exhausted from their journey, the bears rested on the shoreline and fell sound asleep. Over the years, the sand covered them up, creating a huge sand dune.

Attacks on humans

Although an adult bear is quite capable of killing a human, American black bears typically avoid confronting humans when possible. Unlike grizzly bears, which became a subject of fearsome legend among the European settlers of North America, black bears were rarely considered overly dangerous, even though they lived in areas where the pioneers had settled. Black bears rarely attack when confronted by humans, and usually limit themselves to making mock charges, emitting blowing noises and swatting the ground with their forepaws. However, according to Stephen Herrero in his Bear Attacks: Their Causes and Avoidance,<ref name="Herrero"/> 23 people were killed by black bears from 1900 to 1980. The number of black bear attacks on humans is higher than those of the brown bear in North America, though this is largely because the black species considerably outnumbers the brown rather than greater aggressiveness.

File:Bearmailbox.JPG
The incidence of bear attacks in parks and campgrounds declined after the introduction of bear-resistant garbage cans and other reforms

Compared to brown bear attacks, aggressive encounters with black bears rarely lead to serious injury. However, the majority of black bear attacks tend to be motivated by hunger rather than territoriality, and thus victims have a higher probability of surviving by fighting back rather than submitting. Unlike grizzlies, female black bears do not display the same level of protectiveness to their cubs, and seldom attack humans in their vicinity.<ref name="Herrero"/> However, occasionally, attacks by protective mothers do occur.<ref name="Lariviere"/> The worst recorded fatality incident occurred in May 1978, in which a black bear killed three teenagers who were fishing in Algonquin Park in Canada.<ref name="kruuk"/> Another exceptional, spree-like attack occurred in August 1997 in Liard River Hot Springs Provincial Park in Canada, when an emaciated black bear attacked a child and mother, killing the mother as well as an adult man who tried to intervene. This bear was shot while mauling a fourth victim.<ref name="OutdoorLifeApril11999">Template:Cite web</ref><ref name="17Aug1997LAT">Template:Cite news</ref>

The majority of attacks happened in national parks, usually near campgrounds, where the bears had become habituated to close human proximity and food conditioned.<ref name="Herrero"/> 1,028 incidents of black bears acting aggressively toward people, 107 of which resulted in injury, were recorded from 1964 to 1976 in the Great Smoky Mountains National Park, and occurred mainly in tourist hotspots where people regularly fed the bears handouts.<ref name="kruuk">Kruuk, Hans (2002). Hunter and hunted: relationships between carnivores and people, Cambridge University Press, ISBN 0-521-89109-4</ref> In almost every case where open dumps or handouts that had previously attracted black bears were ceased, the amount of aggressive encounters with bears have decreased precipitously over time.<ref name="Lariviere"/> However, in the aforementioned case of the spree attack in Liard River Hot Springs, the attacking bear was believed to have been previously almost fully dependent on a local garbage dump that had closed and was starving as a result of the loss of that food source.<ref name="OutdoorLifeApril11999"/> Attempts to relocate bears are typically unsuccessful, as black bears seem to be able to return to their home range even without familiar landscape cues.<ref name="Lariviere"/>

Livestock and crop predation

A limitation of food sources in early spring and wild berry and nut crop failures during summer months are probably major contributing factors to black bears regularly feeding from commercial human-based food sources. Crops are frequently eaten by these bears, especially during autumn hyperphagia when natural foods are scarce. Favored crops may include apples, oats and corns.<ref name="Hunter"/> Black bears can do extensive damage in some areas of the northwestern United States by stripping the bark from trees and feeding on the cambium. Livestock depredations by black bears occur mostly in spring. Though black bears have the capacity to (and occasionally do) hunt adult cattle and horses, they seem to prefer smaller, more easily overwhelmed prey such as 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 and is frequently found on the neck, back, and shoulders of larger animals. Surplus killing of sheep and goats are 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.<ref name="Predation" /> Occasionally, pets, especially dogs which are most prone to harass a bear, are killed by black bears.<ref>Black Bear Attacks Dog. Wjhg.com. Retrieved on 2012-12-21.</ref> It is not recommended to use unleashed dogs as a deterrent from bear attacks. Although large, aggressive dogs sometimes cause a bear to run, if pressed, angry bears frequently turn the tables and end up chasing the dog in return. A bear in pursuit of a pet dog has the potential to threaten both canid and human lives.<ref>Frequently Asked Questions Regarding Bears – Denali National Park & Preserve. Nps.gov. Retrieved on 2012-12-21.</ref><ref>Encountering Black Bears in Arkansas. University of Arkansas uaex.edu</ref> Template:-

Hunting and exploitation

Hunting

Historically, black bears were hunted by both Native Americans and European settlers. Some Native American tribes,Template:Which in admiration for the black bear's intelligence, would decorate the heads of bears they killed with trinkets, and place them on blankets. Tobacco smoke would be wafted into the disembodied head's nostrils by the hunter that dealt the killing blow, and would compliment the animal for its courage.<ref name="wood"/> The Kutchin typically hunted black bears during their hibernation cycle. Unlike the hunting of hibernating grizzlies, which was wrought with danger, black bears took longer to awaken, and was thus safer and easier.<ref name="kutch"/> During the European colonisation of eastern North America, thousands of black bears were hunted for their meat, fat and fur.<ref name="world"/> Theodore Roosevelt wrote extensively on black bear hunting in his Hunting the Grisly and other sketches, in which he stated "in [a black bear] chase there is much excitement, and occasionally a slight spice of danger, just enough to render it attractive; so it has always been eagerly followed". He wrote that black bears were difficult to hunt by stalking, due to their habitat preferences, though were easy to trap. Roosevelt described how in the Southern States, planters regularly hunted black bears on horseback with hounds. General Wade Hampton was known to have been present at 500 successful black bear hunts, two thirds of which he killed personally. He killed thirty or forty black bears with only a knife, which he would use to stab the bears between the shoulder blades while they were distracted by his hounds.<ref name="TEDDY">Template:Cite book</ref> Unless well trained, horses were often useless in black bear hunts, as they often bolted when the bears stood their ground.<ref name="wood"/> In 1799, 192,000 black bear skins were exported from Quebec. In 1822, 3,000 skins were exported from the Hudson's Bay Company.<ref>Partington, Charles Frederick (1835) The British Cyclopædia of Natural History: Combining a Scientific Classification of Animals, Plants, and Minerals, Vol. 1, Orr & Smith.</ref> In 1992, untanned, fleshed and salted black bear hides were sold for an average of $165.Template:Sfn

In Canada, black bears are considered as both a big game and furbearer species in all provinces save for New Brunswick and Northwest Territories, where they are only classed as a big game species. There are currently 80,822 licensed black bear hunters in all of Canada. Canadian black bear hunts take place in the fall and spring, and both male and female bears can be legally taken, though some provinces prohibit the hunting of females with cubs, or yearling specimens.<ref name="plan"/>

Currently, 28 of the USA's states have black bear hunting seasons. Nineteen states require a bear hunting license, with some also requiring a big game license. In eight states, only a big game license is required to hunt black bears. Overall over 481,500 black bear hunting licences are sold per year. The hunting methods and seasons vary greatly according to state, with some bear hunting seasons including fall only, spring and fall, or year-round. New Jersey, in November 2010, approved of a six-day bear-hunting season in early December 2010 to slow the growth of the black bear population. Bear-hunting had been banned in New Jersey for five years.<ref>Template:Cite web</ref> A Fairleigh Dickinson University PublicMind poll found that 53% of New Jersey voters approved of the new season if scientists concluded black bears were leaving their usual habitats and destroying private property.<ref name="autogenerated1">Template:Cite web</ref> Men, older voters, and those living in rural areas were more likely to approve of a bear-hunting season in New Jersey than women, younger voters, and those living in more developed parts of the state.<ref name="autogenerated1"/> In the western states, where there are large black populations, there are spring and year-round seasons. Approximately 18,845 black bears were killed annually in the USA between 1988–1992. Within this period, annual kills ranged from six bears in South Carolina to 2,232 in Maine.<ref name="plan"/>

According to Dwight Schuh in his Bowhunter's Encyclopedia, black bears are the third most popular quarry of bowhunters, behind deer and elk.<ref>Schuh, Dwight R. (1992) Bowhunter's Encyclopedia, Stackpole Books, ISBN 0-8117-2412-3</ref>

Meat and organs

Black bear meat had historically been held in high esteem among North America's indigenous people and colonists.<ref name="wood"/> Black bears were the only bear species the Kutchin hunted for their meat, though this constituted only a small part of their diet.<ref name="kutch">Nelson, Richard K. Hunters of the northern forest: designs for survival among the Alaskan Kutchin, University of Chicago Press, 1986, ISBN 0-226-57181-5</ref> According to the second volume of Frank Forester's field sports of the United States, and British provinces, of North America:

Template:Bquote

Theodore Roosevelt himself likened the flesh of young black bears to that of pork, and not as coarse or flavourless as the meat of grizzlies.<ref>Roosevelt, Theodore. Hunting Trips of a Ranchman: Hunting Trips on the Prairie and in the Mountains, Adamant Media Corporation, ISBN 1-4212-6647-4</ref> The most favoured cuts of the black bear's meat are concentrated in the legs and loins. Meat from the neck, front legs and shoulders is usually ground into mincemeat or used for stews and casseroles. Keeping the fat tends to give the meat a strong flavour. As black bears can have trichinellosis, cooking temperatures need to be high in order to kill the parasites.<ref name="hunt">Smith, Richard P. (2007) Black Bear Hunting, Stackpole Books, ISBN 0-8117-0269-3</ref>

Black bear fat was once valued as a cosmetic article which promoted hair growth and gloss. The fat most favoured for this purpose was the hard white fat found in the body's interior. As only a small portion of this fat could be harvested for this purpose, the oil was often mixed with large quantities of hog lard.<ref name="wood"/> However animal rights activism over the last decade has slowed the harvest of these animals; therefore the lard from black bear has not been used in recent years for the purpose of cosmetics.

References

  • Powell, Roger A. (1997) Ecology and Behaviour of North American Black Bears: Home Ranges, Habitat, and Social Organization. Chapman & Hall ISBN 0412579901
  • Edgemon, Erin (August 12, 2014) "Black bear sightings in Alabama are on the rise, but is the population growing?" The Birmingham News

External links