Black bear

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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, Georgia and Florida.

Black bears became genetically distinct from brown bears and polar bears just over five 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. 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. Bear Meat Cabin in present-day Jones Valley was son named because it was the home of a trader proffering meat and skins from bears.

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 have been increasing in recent decades, leading to a number of sightings in Alabama. The Little River Canyon is used as a corridor by bears pushed out of the developing areas between Atlanta, Georgia and Chattanooga, Tennessee due to loss of habitat. At least 26 individuals were recorded in the canyon in 2012 and 2013. One tagged female came into the region from Georgia and had a litter of cubs before it was shot and killed by a homeowner. Several bear sightings were reported in Northern Jefferson County in the summer of 2017. One was spotted outside a Waffle House in Leeds in June 2018.

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.

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. Their paws are proportionally large, with black pads and rounded black or dark gray-brown claws. Their tails are vestigial, usually less than 5 inches long.

Black bear 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.

Behavior

Black bears are strong and dexterous. They can lift heavy rocks and operate simple devices such as screw-tops and door knobs. They can run at speeds of up to 30 miles per hour, swim well, and climb trees readily. They have a powerful sense of smell, as well as acute 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 are usually nocturnal, especially when close to human settlements. They 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 dominate the choicest spots. Bears travel long distances and mark their territories by rubbing their bodies against trees and scratching at the bark with their claws.

Bear sows typically produce a first litter of cubs when 3 to 5 years old. 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 sporting 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 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.

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.

Habitat and diet

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 best support bear populations.

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. In colder climates, bears damage trees by stripping the bark to eat the cambium layer of wood. They will also forage farm crops such as apples, corn and oats, and will take small livestock by force, or feed on animals shot by hunters if they are left undisturbed.

Bear attacks

Though typically shying from confrontation, adult bears have occasionally attacked humans, sometimes killing them. These attacks seem to be motivated by hunger, occurring in park settings where bears become accustomed to finding food at picnic or camping areas. Park officials have been successful in reducing aggressive bear behaviors by enforcing safeguards on food and garbage. If forced into confrontation, a threatened black bear may roar, swat the ground, or make mock charges rather than actually attacking. If harassed, as by an aggressive dog, a bear will give chase. Black bear mothers are not unusually protective toward their cubs, as Grizzly bears are.

Hunting and trapping

The settlement of North America was undertaken in concert with large-scale hunting of black bears for protection, commercial exploitation, and recreation. Bear skins were valued by furriers in Europe and constituted a major economic resource to trappers in Canada and the northern United States. Black bear fat, specifically the hard fat from the interior, was once valued as a cosmetic article which was thought to promote hair growth while providing an attractive gloss.

In the South, bear hunting was a popular sport for the wealthy, who often used dogs to chase and hold them at bay before killing them from horseback. Bear hunting remains legal in 28 states with varying seasons, limits and licensing requirements. Maine is the state with the largest number of licenses issued and kills reported.

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
  • Edgemon, Erin (November 4, 2014) "Auburn researchers begin trapping, putting GPS collars on 20 black bears; Little River Canyon joins statewide study". The Birmingham News
  • Robinson, Carol (June 26, 2017) "It was a bear of a weekend in northern Jefferson County; game cameras capture sightings." The Birmingham News

External links