Everything about The Brown Bear totally explained
The
brown bear (
Ursus arctos) is an
omnivorous mammal of the order
carnivora, distributed across much of northern
Eurasia and
North America. It weighs between 100–700 kg (220-1,500
pounds) and its larger populations match the
Polar bear as the largest extant land carnivores. While the brown bear's range has shrunk, and it has faced local extinctions, it remains listed as a
least concern species with a total population of approximately 200,000. Its principal range countries are
Russia, the
United States (especially
Alaska), and
Canada.
The species primarily feeds on vegetable matter, including
roots and
fungi.
Fish are a primary source of meat, and it'll also kill small mammals on land. Larger mammals, such as
deer, are taken only occasionally. Adult brown bears face no serious competition from other predators and can match wolf packs and large felines, often driving them off their kills.
It is sometimes referred to as the
bruin, from Middle English, based on the name of the bear in
History of Reynard the Fox, translated by
William Caxton, from Middle Dutch
bruun or
bruyn.
Description
Brown bears have furry coats in shades of blonde, brown, black, or a combination of those colors. The longer outer guard hairs of the brown bear are often tipped with white or silver, giving a "grizzled" appearance. Their tail is 4-5 inches long. Like all bears, brown bears are
plantigrades and can stand up on their hind legs for extended periods of time. Brown bears have a large hump of
muscle over their shoulders which distinguishes them from other species. Brown bears are very powerful, even if considered pound for pound; a large specimen can break a neck or spine of a fully grown buffalo with a single blow. The forearms end in massive paws with claws up to 15 cm (6 inches) in length which are mainly used for digging. Brown bear claws are not retractable, and have relatively blunt points. Their heads are large and round with a facial profile, a characteristic used to distinguish them from other bears. Males are 38-50% larger than females. The normal range of physical dimensions for a brown bear is a head-and-body length of 1.7 to 2.8 m (5.6 to 9.2 feet) and a shoulder height 90 to 150 cm (35 to 60 inches). The smallest subspecies is the
Eurasian Brown Bear with mature females weighing as little as 90 kg (200 lb). Barely larger,
Grizzly Bears from the
Yukon region (which are a third smaller than most grizzlies) can weigh as little as 100 kg (220 lb) in the spring and the
Syrian Brown Bear, with mature females weighing as little as 150 kg (331 lb). The largest subspecies of the brown bear are the
Kodiak bear and the bears from coastal
Russia and
Alaska. It isn't unusual for large male Kodiak Bears to stand over 3 m (10 feet) while on their hind legs and to weigh about 680 kg (1,500 lb). The largest wild Kodiak bear on record weighed over 1,100 kilograms (2,500 pounds).. Bears raised in zoos are often heavier than wild bears because of regular feeding and limited movement. In zoos, bears may weigh up to 900 kilograms (2,000 pounds), one example being "Goliath" from New Jersey's
Space Farms Zoo and Museum. Size seems related to food availability, with subspecies distinctions being more related to nutrition rather than geographical location.
In spite of their size, some brown bears have been clocked at speeds in excess of 56 km/h (35 mph).
Distribution and habitat
There are about 200,000 brown bears in the world. The largest populations are in Russia, with 120,000, the United States with 32,500, and Canada with 21,750. 95% of the brown bear population in the United States is in Alaska, though in the West they're repopulating slowly but steadily along the
Rockies and plains. Although many hold on to the belief that some brown bears may be present in Mexico and the Atlas Mountains of Morocco, both are almost certainly extinct. The last Mexican brown bear was shot in 1960. In Europe, there are 14,000 brown bears in ten separate fragmented populations, from
Spain in the west, to
Russia in the east, and from
Scandinavia in the north to
Romania and
Bulgaria in the south. They are extinct in the
British Isles, extremely threatened in
France and Spain, and in trouble over most of Central Europe. The brown bear is
Finland's national animal. The Carpathian brown bear population is the largest in Europe outside Russia, estimated at 4,500 to 5,000 bears.
Brown bears were once native to
Asia, the
Atlas Mountains in
Africa,
Europe and
North America, but are now
extinct in some areas and their populations have greatly decreased in other areas. They prefer semi-open country, usually in mountainous areas.
Brown bears live in
Alaska, east through the
Yukon and
Northwest Territories, south through
British Columbia and through the western half of
Alberta. Isolated populations exist in northwestern
Washington, northern
Idaho, western
Montana, and northwestern
Wyoming.
The population of brown bears in the
Pyrenees mountain range between
France and
Spain is so low, estimated at fourteen to eighteen with a shortage of females, that bears, mostly female, from
Slovenia were released in the spring of 2006 to alleviate the imbalance and preserve the species' presence in the area, despite protests from French farmers.
In
Arctic areas, the potential habitat of the brown bear is increasing. The warming of that region has allowed the species to move farther and farther north into what was once exclusively the domain of the
polar bear. In non-Arctic areas, habitat loss is blamed as the leading cause of endangerment, followed by hunting.
North American brown bears seem to prefer open landscapes, whereas in Eurasia they inhabit mostly dense forests. It is thought that the Eurasian bears which colonized America were tundra adapted, something indicated by brown bears in the
Chukotka Peninsula on the Asian side of Bering Strait, which are the only Asian brown bears to live year-round in lowland tundra like their American cousins.
Brown bear in prehistory
North America
The brown bear has existed in North America since at least the most recent ice age, though it's thought that the larger, taller, and stronger
giant short-faced bear or bulldog bear was the dominant carnivore at the time. The giant short-faced bear was a tall, thin animal adapted to eating large mammals, whereas the grizzly or brown bear has teeth appropriate for its
omnivorous diet.
The brown bear also shared North America with the
American lion and
Smilodon, carnivorous competitors. The modern grizzly can eat plants, insects, carrion, and small and large animals. The American lion, Smilodon, and giant short-faced bear had a more limited range of food, making them vulnerable to starvation as the supply of available large mammals decreased, possibly due to hunting by humans.
The time of the
Arctodus extinction is about the same as that of the
long-horned Bison and other
megafauna. Both of these animals were replaced by Eurasian immigrants, specifically the Brown Bear and
American Bison. Since this was also about the same time as the
Clovis tool kit hunting culture appeared in North America, with culturally advanced humans entering the Americas from Asia, the implication is that the brown bear was better adapted to human competition than the megafauna, presumably due to a long term coexistence in the Old World with people.
The extinction of ice-age herbivorous megafauna resulted in the extinction of the sabertooth, American lion, and giant short-faced bear, leaving the brown bear as the major large predator in North America, with the
gray wolf, the
jaguar in the south, the
American black bear, and
cougar also competing for large prey. The origin of human presence in America is widely accepted to have occurred across the
Bering Land Bridge with the largest known immigration being that of the
Paleo Indians at about the last ice age, bringing with them the
Clovis point and advanced hunting techniques (see:
Migration to the New World). When the last ice age ended about 10,000 years ago, brown bears from farther south in North America slowly expanded their range northward and back up into Alaska. Today there are three
genetically distinct grizzly bear
clades in North America: the Alaskan-Yukon Grizzly, the Alberta-
Saskatchewan lineage, and those found in the Washington-Idaho-Montana-Wyoming area.
Eurasia
In Europe, the brown bear shared its habitat with other predators such as the
Cave lion,
Cave hyena and the larger, closely related
Cave bear, which the brown bear ultimately outlasted. The cave bear was hunted by
Neanderthals who may have had a religion relating to this bear, the
Cave Bear Cult, but the Neanderthal population was too small for their consumption of cave bear to result in the species' extinction, and the cave bear outlasted the Neanderthals by 18,000 years, becoming extinct about 10,000 years ago. The cave bear and brown bear diets were similar, and the two species probably lived in the same area at the same time. Why the cave bear died out isn't known.
Behavior
The brown bear is primarily
nocturnal and, in the summer, puts on up to 180 kg (400 pounds) of
fat, on which it relies to make it through winter, when it becomes very lethargic. Although they're not full
hibernators, and can be woken easily, both sexes like to den in a protected spot such as a
cave, crevice, or hollow log during the winter months. Brown bear are mostly solitary, although they may gather in large numbers at major food sources and form social hierarchies based on age and size.
Reproduction
[[Image:Bearand cubs fapas.jpg|thumb|200px|right|Female
Cantabrian brown bear and cubs. With kind permission of [http://www.fapas.es Fapas] (Conservation NGO - Foundation for the Protection of Wild Animals)
]]
The mating season takes place from late May through early July. Being serially
monogamous, brown bears will remain with the same mate from several days to a couple of weeks. Females become sexually mature between the age of 5 and 7 years, while males will usually not mate until a few years later when they're large and strong enough to successfully compete with other males for mating rights.
Through the process of
delayed implantation, a female's fertilized egg will divide and float free within the uterus for six months. During winter dormancy, the fetus will attach itself to the uterine wall and the cubs will be born after an eight-week period while the mother sleeps. Should the mother not gain enough weight to survive through the winter, the embryo won't implant and be reabsorbed into the body. The average litter number is between one and four, with two being the most common number, though there have been cases of bears with five cubs, though it isn't unusual for females to adopt strange cubs. The size of a litter depends on a number of factors such as the age of the mother, geographic location and food supply. Older females tend to give birth to larger litters. The cubs are blind, toothless, hairless and weigh less than 1 pound at birth. They feed on their mother’s milk until spring and as late as early summer depending on climate conditions. The cubs, which will weigh from 15 to 20 pounds at this time, will have developed enough to follow her and begin to forage for solid food.
Cubs will remain with their mother from two to four years, during which time that'll learn survival techniques such as which foods have the highest nutritional values and where to attain them, how to hunt, how to fish, how to defend themselves and where to den. The cubs learn by following and imitating their mother’s actions during the period they're with her. Brown bears practice
infanticide. An adult male bear will kill the cubs of another bear to make the female sexually receptive. Cubs will flee up a tree when they sight a strange male bear.
Dietary habits
They are
omnivores and feed on a variety of plant products, including berries,
roots, and
sprouts,
fungi as well as meat products such as
fish,
insects, and small
mammals. Despite their reputation, most brown bears are not particularly carnivorous as they derive up to 90% of their dietary
food energy from vegetable matter.
(External Link
) Their jaw structure has evolved to fit their dietary habits. Their diet varies enormously throughout their differing ranges. For example, bears in Yellowstone eat an enormous number of
moths during the summer, sometimes as many as 40,000 in a day,
(External Link) and may derive up to a third of their food energy from these insects.
(External Link) Locally, in areas of Russia and Alaska, brown bears feed mostly on spawning salmon, and the nutrition and abundance of this food accounts for the enormous size of the bears from these areas. Brown bears also occasionally prey on
deer (
Odocoeilus spp.;
Dama spp.,
Capreolus spp.),
Red Deer (
Cervus elaphus or American elk),
Moose (
Alces alces),
Caribou (
Rangifer tarandus) and
Bison (
Bison bison spp.,
Bison bonasus). When brown bears attack these animals, they tend to choose the young ones since they're much easier to catch. When hunting, the brown bear uses its sharp canine teeth for neck-biting its prey. They also feed on
carrion and will use their size to intimidate other predators such as
wolves,
cougars,
black bears and
tigers from their kills.
Interspecific predatory relationships
Brown bears will often use their large size to intimidate
wolves from their kills. In Yellowstone National Park, brown bears pirate wolf kills so often that Yellowstone’s Wolf Project Director Doug Smith once wrote: "It’s not a matter of if the bears will come calling after a kill, but when." Though conflict over carcasses is common, the two predators will on some rare occasions tolerate each other on the same kill. Both species will prey on each others cubs, given the opportunity.
Adults bears are generally immune from predatory attacks from anything other than another bear, however, in the
Russian Far East brown bears, along with smaller
Asiatic black bears constitute 5-8% of the diet of
Siberian tigers. In particular, the brown bear's input is estimated as 1-1,5%. However, for the tiger, even bears of the same size are a force to be reckoned with when confronted head on. Scientists also report incidents when tigers were killed and eaten by brown bears. There is an opinion that the brown bear vs tiger conflict can eliminate the weakest animals from both populations. Some bears emerging from hibernation will seek out tigers in order to steal their kills. Tigers will usually stand their ground and defend their kills, unless the bear is a large male.
Brown bears usually dominate other bear species in areas where they coexist. Due to their smaller size,
American black bears are at a competitive disadvantage over 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're sympatric.
There has been a recent increase in interactions between brown bears and
polar bears, theorized to be caused by
global warming. Brown bears have been seen moving increasingly northward into territories formerly claimed by polar bears. Brown bears tend to dominate polar bears in disputes over carcasses, and dead polar bear cubs have been found in brown bear dens.
Giant Panda cubs have also been reportedly eaten by brown bears.
Habituation to human areas
Bears become attracted to human created food sources such as garbage dumps, litter bins, and dumpsters; and venture into human dwellings or barns in search of food as humans encroach into bear habitat. In the U.S., bears sometimes kill and eat farm animals. When bears come to associate human activity with a "food reward", a bear is likely to continue to become emboldened and the likeliness of human-bear encounters increases, as they may return to the same location despite relocation. The saying, "a fed bear is a dead bear," has come into use to popularize the idea that allowing bears to scavenge human garbage, such as trash cans and campers' backpacks, pet food, or other food sources that draw the bear into contact with humans can result in a bear's death.
Relocation has been used to separate the bear from the human environment, but it doesn't address the problem bear's newly learned humans-as-food-source behavior. Nor does it address the environmental situations which created the human habituated bear. "Placing a bear in habitat used by other bears may lead to competition and social conflict, and result in the injury or death of the less dominant bear."
Yellowstone National Park, an enormous reserve located in the Western United States, contains prime habitat for the Grizzly Bear (
Ursus arctos horribilis), but due to the enormous number of visitors, human-bear encounters are common. The scenic beauty of the area has led to an influx of people moving into the area. In addition, because there are so many bear relocations to the same remote areas of Yellowstone, and because male bears tend to dominate the center of the relocation zone, female bears tend to be pushed to the boundaries of the region and beyond. The result is that a large proportion of repeat offenders, bears that are killed for public safety, are females. This creates a further depressive effect on an already endangered species. The grizzly bear is officially described as
threatened in the U.S. Though the problem is most significant with regard to grizzlies, these issues affect the other types of brown bear as well.
In Europe, part of the problem lies with
shepherds; over the past two centuries, many sheep and goat herders have gradually abandoned the more traditional practice of using
dogs to guard flocks, which have concurrently grown larger. Typically they allow the herds to graze freely over sizeable tracts of land. As bears reclaim parts of their range, they may eat livestock. The shepherd is forced to shoot the bear to protect his livelihood.
Subspecies
There is little agreement on classification of brown bears. Some systems have proposed as many as 90 sub-species while recent DNA analysis has identified as few as five clades. DNA analysis has recently revealed that the identified subspecies of brown bears, both Eurasian and North American, are genetically quite homogeneous, and that their genetic
phylogeography doesn't correspond to their traditional taxonomy. The subspecies of brown bears have been listed as follows: one of which (called clade I by Waits, et al., part of the subspecies identified as
U. a. sitkensis, by Hall and
U. a. dalli by Kurtén) appears to be more closely related to the
polar bear than to other brown bears. Previously, the hybrid had been produced in zoos and was considered a "
cryptid" (a hypothesized animal for which there's no scientific proof of existence in the wild).
Legal status
The grizzly bear, sometimes called the silvertip bear, is listed as threatened in the Continental United States. It is currently slowly repopulating in areas where it was previously extirpated, though it's still vulnerable.
The California golden bear (Ursus arctos californicus) disappeared from the state of California in 1922 when the last one was shot in Tulare County, but it's still on the state flag of California. The bear is alluded to in the names of the sports teams of the University of California, Berkeley (the California Golden Bears), and of the University of California, Los Angeles (the UCLA Bruins) and in the mascot of University of California, Riverside (Scottie the Bear, dressed in a Highland kilt).
The Mexican grizzly bear is listed as an endangered species, but it may be extinct.
In Canada, it's listed as vulnerable in Alberta, British Columbia, Northwest Territories, and Yukon Territory. Prairie populations of grizzly bear are listed as extirpated in Alberta, Manitoba, and Saskatchewan.
The brown bear is a European Protected Species, given protection throughout the European Union.
The brown bear is also the national animal of Finland and Slovenia.
Bear encounters
There are an average of two fatal attacks a year in North America. In Scandinavia, there are only four known cases during the last 100 years in which humans were killed by bears. The two most common causes for bear attack are surprise and curiosity. Some types of bears, such as polar bears, are more likely to attack humans when searching for food, while American black bears are much less likely to attack.
The Alaska Science Center ranks the following as the most likely reasons for bear attacks:
1) Surprise
2) Curiosity
3) Invaded personal space
4) Predatory
5) Hunting wounded
6) Carcass defense
7) Provoked charge
History of bear defense
Statiscally, killing a bear has sometimes been the only method of defense. Too often people don't carry a proper caliber weapon to neutralize the bear. According to the Alaska Science Center, a 12 gauge shotgun with slugs has been the most effective weapon. There have been fewer injuries as a result of only carrying lethal loads in the shotgun, as opposed to deterrent rounds. State of Alaska DLP laws require you to salvage the hide, skull and claws.
If a bear is killed near camp the bear’s carcass must be adequately disposed of, including entrails and blood if possible. Failure to move the carcass has often resulted in it attracting other bears and further exacerbating a bad situation.
Further Information
Get more info on 'Brown Bear'.
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