The grizzly bear (Ursus arctos ssp.) is a large subspecies of brown
bear inhabiting North America. Scientists generally do not use the
name grizzly bear but call it the North American brown bear.
Multiple morphological forms sometimes recognized as subspecies exist,
including the mainland grizzly (Ursus arctos horribilis), Kodiak bear
(U. a. middendorffi), peninsular grizzly (U. a. gyas), and the
California grizzly (U. a. californicus†) and
Mexican grizzly bear
Mexican grizzly bear (U. a. nelsoni†). On average bears near the
coast tend to be larger while inland grizzlies tend to be smaller.
Ussuri brown bear
Ussuri brown bear (U. a. lasiotus) inhabiting Russia, Northern
China, and Korea is sometimes referred to as the black
grizzly, although it is a different subspecies from the bears in
1.1 Meaning of "grizzly"
1.2 Evolution and genetics
1.2.1 Grizzly phylogenetics
1.2.2 Ursus arctos - the brown bear
1.2.3 Ursus arctos subspecies in North America
3 Range and population
3.1 Continental United States
4.4 Unique behaviors
5.2 Interspecific competition
5.3 Ecological role
6 Interaction with humans
6.1 Conflicts with humans
6.3 Conservation efforts
7 See also
9 Further reading
10 External links
Meaning of "grizzly"
Meriwether Lewis and
William Clark first described it as grisley,
which could be interpreted as either "grizzly" (i.e.,
"grizzled"—that is, with golden and grey tips of the hair) or
"grisly" ("fear-inspiring", now usually "gruesome"). The modern
spelling supposes the former meaning; even so, naturalist George Ord
formally classified it in 1815 as U. horribilis, not for its hair, but
for its character.
Evolution and genetics
Classification has been revised along genetic lines. There are two
morphological forms of Ursus arctos, the grizzly and the coastal brown
bears, but these morphological forms do not have distinct mtDNA
Ursus arctos - the brown bear
Brown bears originated in
Eurasia and traveled to North America
approximately 50,000 years ago, spreading into the contiguous
United States about 13,000 years ago. In the 19th century, the
grizzly was classified as 86 distinct species. However, by 1928 only
seven grizzlies remained and by 1953 only one species remained
globally. However, modern genetic testing reveals the grizzly to
be a subspecies of the brown bear (Ursus arctos). Rausch found that
North America has but one species of grizzly. Therefore,
everywhere it is the "brown bear"; in North America, it is the
"grizzly", but these are all the same species, Ursus arctos.
Ursus arctos subspecies in North America
In 1963 Rausch reduced the number of North American subspecies to one,
Ursus arctos middendorffi
Further testing of Y-chromosomes is required to yield an accurate new
taxonomy with different subspecies.
Coastal grizzlies, often referred to by the popular but geographically
redundant synonym of "brown bear" or "Alaskan brown bear" are larger
and darker than inland grizzlies, which is why they, too, were
considered a different species from grizzlies. Kodiak grizzly bears
were also at one time considered distinct. Therefore, at one time
there were five different "species" of brown bear, including three in
Most adult female grizzlies weigh 130–180 kg
(290–400 lb), while adult males weigh on average
180–360 kg (400–790 lb). Average total length in this
subspecies is 198 cm (6.50 ft), with an average shoulder
height of 102 cm (3.35 ft) and hindfoot length of 28 cm
(11 in). Newborn bears may weigh less than 500 grams
(1.1 lb). In the
Yukon River area, mature female grizzlies can
weigh as little as 100 kg (220 lb). One study found that the
average weight for an inland male grizzly was around
272 kilograms (600 lb) and the average weight for a coastal
male was around 408 kilograms (900 lb). For a female, these
average weights would be 136 kilograms (300 lb) inland and
227 kilograms (500 lb) coastal, respectively. On the
other hand, an occasional huge male grizzly has been recorded which
greatly exceeds ordinary size, with weights reported up to 680 kg
(1,500 lb). A large coastal male of this size may stand up to
3 metres (9.8 ft) tall on its hind legs and be up to 1.5 metres
(4.9 ft) at the shoulder.
Although variable in color from blond to nearly black, grizzly bear
fur is typically brown with darker legs and commonly white or blond
tipped fur on the flank and back. A pronounced hump appears on
their shoulders; the hump is a good way to distinguish a grizzly bear
from a black bear, as black bears do not have this hump. Aside from
the distinguishing hump a grizzly bear can be identified by a "dished
in" profile of their face with short, rounded ears, whereas a black
bear has a straight face profile and longer ears. A grizzly bear
can also be identified by its rump, which is lower than its shoulders,
while a black bear's rump is higher. A grizzly bear's front claws
measure about 2-4 inches in length and a black bear's measure about
1-2 inches in length.
Range and population
Grizzly bear in Katmai National Park with partially eaten salmon - the
heads, skin and subcutaneous tissue are eaten to obtain the most fat.
Brown bears are found in Asia, Europe, and North America, giving them
the widest ranges of bear species. They also inhabited North Africa
and the Middle East. In North America, grizzly bears previously
Alaska down to
Mexico and as far east as the western
shores of Hudson Bay; the species is now found in Alaska, south
through much of western Canada, and into portions of the northwestern
United States (including Idaho, Montana, Washington, and Wyoming),
extending as far south as Yellowstone and Grand Teton National Parks.
It is most commonly found in Canada. In Canada, there are
approximately 25,000 grizzly bears occupying British Columbia,
Alberta, the Yukon, the Northwest Territories, Nunavut, and the
northern part of Manitoba. An article published in 1954 suggested
they may be present in the tundra areas of the
Ungava Peninsula and
the northern tip of Labrador-Quebec. In British Columbia, grizzly
bears inhabit approximately 90% of their original territory. There
were approximately 25,000 grizzly bears in
British Columbia when the
European settlers arrived. However, population size has since
significantly decreased due to hunting and habitat loss. In 2003,
researchers from the University of
Alberta spotted a grizzly on
Melville Island in the high Arctic, which is the most northerly
sighting ever documented. In 2008, it was estimated there were
16,014 grizzly bears. Population estimates for
British Columbia are
based on hair-snagging, DNA-based inventories, mark-and-recapture, and
a refined multiple regression model. A revised
Grizzly bear count
in 2012 for
British Columbia was 15,075.
The Alaskan population of 30,000 individuals is the highest population
of any province/state in North America. Populations in
densest along the coast, where food supplies such as salmon are more
Admiralty Island National Monument
Admiralty Island National Monument protects the
densest population — 1,600 bears on a 1,600-square mile island.
Continental United States
Only about 1,500 grizzlies are left in the lower 48 states of the
US. Of these, about 800 live in Montana. About 600 more live
in Wyoming, in the Yellowstone-Teton area. There are an estimated
70–100 grizzly bears living in northern and eastern Idaho. Its
original range included much of the
Great Plains and the southwestern
states, but it has been extirpated in most of those areas. Combining
Canada and the United States, grizzly bears inhabit approximately half
the area of their historical range.
Although the once-abundant grizzly bear (see
California grizzly bear)
appears prominently on the state flag of
California and was the symbol
Bear Flag Republic before California's admission to the Union,
they are no longer naturally present. The last grizzly in all of
California was killed in the Sierra foothills east of
Fresno in August
In September 2007, a hunter produced evidence of one bear in the
Selway-Bitterroot Wilderness ecosystem, by killing a male grizzly bear
there. In the
North Cascades ecosystem of northern Washington,
grizzly bear populations are estimated to be less than 20 bears. One
sighting of a grizzly bear in 2010 has been recorded. There has
been no confirmed sighting of a grizzly in Colorado since 1979.
Other provinces and the
United States may use a combination of methods
for population estimates. Therefore, it is difficult to say precisely
what methods were used to produce total population estimates for
Canada and North America, as they were likely developed from a variety
of studies. The grizzly bear currently has legal protection in Mexico,
European countries, some areas of
Canada and in the United States.
However, it is expected that repopulating its former range will be a
slow process, due to a variety of reasons including the bear's slow
reproductive habits and the effects of reintroducing such a large
animal to areas prized for agriculture and livestock. Competition with
other predators and predation on cubs are other possible limiting
factors for grizzly bear recovery, though grizzly bears also benefit
from scavenged carcasses from predators as an easy food source when
other food sources decline. There are currently about 55,000 wild
grizzly bears total located throughout North America, most of which
reside in Alaska.
Grizzly bears hibernate for 5–7 months each year except where
the climate is warm, as the
California grizzly did not hibernate.
During this time, female grizzly bears give birth to their offspring,
who then consume milk from their mother and gain strength for the
remainder of the hibernation period. To prepare for hibernation,
grizzlies must prepare a den, and consume an immense amount of food as
they do not eat during hibernation. Grizzly bears do not defecate or
urinate throughout the entire hibernation period. The male grizzly
bear's hibernation ends in early to mid-March, while females emerge in
April or early May.
In preparation for winter, bears can gain approximately 180 kg
(400 lb), during a period of hyperphagia, before going into
hibernation. The bear often waits for a substantial snowstorm
before it enters its den: such behavior lessens the chances predators
will find the den. The dens are typically at elevations above
1,800 m (5,900 ft) on north-facing slopes. There is some
debate amongst professionals as to whether grizzly bears technically
hibernate: much of this debate revolves around body temperature and
the ability of the bears to move around during hibernation on
occasion. Grizzly bears can "partially" recycle their body wastes
during this period. Although inland or Rocky Mountain grizzlies
spend nearly half of their life in dens, coastal grizzlies with better
access to food sources spend less time in dens. In some areas where
food is very plentiful year round, grizzly bears skip hibernation
Sow with two cubs in the Kananaskis
Except for females with cubs, grizzlies are normally solitary,
active animals, but in coastal areas, grizzlies gather around streams,
lakes, rivers, and ponds during the salmon spawn. Every other year,
females (sows) produce one to four young (usually two) that are small
and weigh only about 450 grams (1 lb) at birth. A sow is
protective of her offspring and will attack if she thinks she or her
cubs are threatened.
Grizzly bears have one of the lowest reproductive rates of all
terrestrial mammals in North America. This is due to numerous
ecological factors. Grizzly bears do not reach sexual maturity until
they are at least five years old. Once mated with a male in the
summer, the female delays embryo implantation until hibernation,
during which miscarriage can occur if the female does not receive the
proper nutrients and caloric intake. On average, females produce
two cubs in a litter and the mother cares for the cubs for up to
two years, during which the mother will not mate.
Mother grizzly with a cub
Once the young leave or are killed, females may not produce another
litter for three or more years, depending on environmental
conditions. Male grizzly bears have large territories, up to
4,000 km2 (1,500 sq mi), making finding a female
scent difficult in such low population densities. Population
fragmentation of grizzlies may destabilize the population from
inbreeding depression. The gestation period for grizzly bears is
approximately 180–250 days.
Litter size is between one and four cubs, averaging twins or triplets.
Cubs are always born in the mother's winter den while she is in
hibernation. Female grizzlies are fiercely protective of their cubs,
being able to fend off predators as large as male bears bigger than
they are in defense of the cubs. Cubs feed entirely on their
mother's milk until summer comes, after which they still drink milk
but begin to eat solid foods. Cubs gain weight rapidly during their
time with the mother — their weight will have ballooned from 4.5 to
45 kg (10 to 99 lb) in the two years spent with the mother.
Mothers may see their cubs in later years but both avoid each
The grizzly bear is, by nature, a long-living animal. The average
lifespan for a male is estimated at 22 years, with that of a female
being slightly longer at 26. Females live longer than males due to
their less dangerous life; avoiding the seasonal breeding fights in
which males engage. The oldest wild inland grizzly was 34 years old in
Alaska; the oldest coastal bear was 39, but most grizzlies die in
their first few years of life from predation or hunting. Captive
grizzlies have lived as long as 44 years.
The grizzly bear has been observed to be an extraordinarily talented
dancer as pictured by
David Attenborough in the Planet Earth II
See also: Hypocarnivore
Although grizzlies are of the order
Carnivora and have the digestive
system of carnivores, they are normally omnivores: their diets consist
of both plants and animals. They have been known to prey on large
mammals, when available, such as moose, elk, caribou, white-tailed
deer, mule deer, bighorn sheep, bison, and even black bears; though
they are more likely to take calves and injured individuals rather
than healthy adults. Grizzly bears feed on fish such as salmon, trout,
and bass, and those with access to a more protein-enriched diet in
coastal areas potentially grow larger than inland individuals. Grizzly
bears also readily scavenge food or carrion left behind by other
animals. Grizzly bears will also eat birds and their eggs, and
gather in large numbers at fishing sites to feed on spawning salmon.
They frequently prey on baby deer left in the grass, and occasionally
they raid the nests of raptors such as bald eagles.
Canadian or Alaskan grizzlies are larger than those that reside in the
American Rocky Mountains. This is due, in part, to the richness of
their diets. In
Yellowstone National Park
Yellowstone National Park in the United States, the
grizzly bear's diet consists mostly of whitebark pine nuts, tubers,
grasses, various rodents, army cutworm moths, and scavenged
carcasses. None of these, however, match the fat content of the
salmon available in
Alaska and British Columbia. With the high fat
content of salmon, it is not uncommon to encounter grizzlies in Alaska
weighing 540 kg (1,200 lb). Grizzlies in Alaska
supplement their diet of salmon and clams with sedge grass and
berries. In areas where salmon are forced to leap waterfalls,
grizzlies gather at the base of the falls to feed on and catch the
Salmon are at a disadvantage when they leap waterfalls because
they cluster together at their bases and are therefore easier targets
for the grizzlies. Grizzly bears are well-documented catching
leaping salmon in their mouths at
Brooks Falls in Katmai National Park
and Preserve in Alaska. They are also very experienced in chasing the
fish around and pinning them with their claws. At such sites
Brooks Falls and
McNeil Falls in Alaska, big male grizzlies
fight regularly for the best fishing spots. Grizzly bears along
the coast also forage for razor clams, and frequently dig into the
sand to seek them. During the spring and fall, directly before and
after the salmon runs, berries and grass make up the mainstay of the
diets of coastal grizzlies.
Grizzly bear fishing for salmon at Brooks Falls, Alaska
Inland grizzlies may eat fish too, most notably in Yellowstone
grizzlies eating Yellowstone cutthroat trout. The relationship
with cutthroat trout and grizzlies is unique because it is the only
example where Rocky Mountain grizzlies feed on spawning salmonid
fish. However, grizzly bears themselves and invasive lake trout
threaten the survival of the trout population and there is a slight
chance that the trout will be eliminated.
Meat, as already described, is an important part of a grizzly's diet.
Grizzly bears occasionally prey on small mammals, such as marmots,
ground squirrels, lemmings, and voles. The most famous example of
such predation is in
Denali National Park and Preserve, where
grizzlies chase, pounce on, and dig up Arctic ground squirrels to
eat. In some areas, grizzly bears prey on hoary marmots,
overturning rocks to reach them, and in some cases preying on them
when they are in hibernation. Larger prey includes bison and
moose, which are sometimes taken by bears in Yellowstone National
Park. Because bison and moose are dangerous prey, grizzlies usually
use cover to stalk them and/or pick off weak individuals or
calves. Grizzlies in
Alaska also regularly prey on moose
calves, which in
Denali National Park may be their main source of
meat. In fact, grizzly bears are such important predators of moose and
elk calves in
Alaska and in Yellowstone, that they may kill as many as
51 percent of elk or moose calves born that year. Grizzly bears have
also been blamed in the decline of elk in Yellowstone National Park
when the actual predators were thought to be gray
wolves. In northern Alaska, grizzlies are a
significant predator of caribou, mostly taking sick or old individuals
or calves. Several studies show that grizzly bears may follow the
caribou herds year-round in order to maintain their food
supply. In northern Alaska, grizzly bears often encounter
muskox. Despite the fact that muskox do not usually occur in grizzly
habitat and that they are bigger and more powerful than caribou,
predation on muskox by grizzlies has been recorded.
Grizzly bears along the Alaskan coast also scavenge on dead or washed
up whales. Usually such incidents involve only one or two
grizzlies at a carcass, but up to ten large males have been seen at a
time eating a dead humpback whale. Dead seals and sea lions are also
Although the diets of grizzly bears vary extensively based on seasonal
and regional changes, plants make up a large portion of them, with
some estimates as high as 80–90%. Various berries constitute an
important food source when they are available. These can include
blueberries, blackberries (Rubus fruticosus), salmon berries (Rubus
spectabilis), cranberries (Vaccinium oxycoccos), buffalo berries
(Shepherdia argentea), soapberries (Shepherdia canadensis), and
huckleberries (Vaccinium parvifolium), depending on the environment.
Insects such as ladybugs, ants, and bees are eaten if they are
available in large quantities. In Yellowstone National Park, grizzly
bears may obtain half of their yearly caloric needs by feeding on
miller moths that congregate on mountain slopes. When food is
abundant, grizzly bears will feed in groups. For example, many grizzly
bears will visit meadows right after an avalanche or glacier slide.
This is due to an influx of legumes, such as Hedysarum, which the
grizzlies consume in massive amounts. When food sources become
scarcer, however, they separate once again.
Grizzly bear cub in Western Canada
The removal of wolves and the grizzly bear in
California may have
greatly reduced the abundance of the endangered San Joaquin Kit
Fox. With the reintroduction of gray wolves to Yellowstone, many
visitors have witnessed a once common struggle between a keystone
species, the grizzly bear, and its historic rival, the gray wolf. The
interactions of grizzly bears with the wolves of Yellowstone have been
under considerable study. Typically, the conflict will be in the
defense of young or over a carcass, which is commonly an elk killed by
wolves. The grizzly bear uses its keen sense of smell to locate
the kill. As the wolves and grizzly compete for the kill, one wolf may
try to distract the bear while the others feed. The bear then may
retaliate by chasing the wolves. If the wolves become aggressive with
the bear, it is normally in the form of quick nips at its hind legs.
Thus, the bear will sit down and use its ability to protect itself in
a full circle. Rarely do interactions such as these end in death or
serious injury to either animal. One carcass simply is not usually
worth the risk to the wolves (if the bear has the upper hand due to
strength and size) or to the bear (if the wolves are too numerous or
persistent). While wolves usually dominate grizzly bears during
interactions at wolf dens, both grizzly and black bears have been
reported killing wolves and their cubs at wolf dens even when the
latter was in defense mode.
Black bears generally stay out of grizzly territory, but grizzlies may
occasionally enter black bear terrain to obtain food sources both
bears enjoy, such as pine nuts, acorns, mushrooms, and berries. When a
black bear sees a grizzly coming, it either turns tail and runs or
climbs a tree. Black bears are not strong competition for prey because
they have a more herbivorous diet. Confrontations are rare because of
the differences in size, habitats, and diets of the bear species. When
this happens, it is usually with the grizzly being the aggressor. The
black bear will only fight when it is a smaller grizzly such as a
yearling or when the black bear has no other choice but to defend
itself. There is at least one confirmed observation of a grizzly bear
digging out, killing and eating a black bear when the latter was in
The segregation of black bear and grizzly bear populations is possibly
due to competitive exclusion. In certain areas, grizzly bears
outcompete black bears for the same resources. For example, many
Pacific coastal islands off
British Columbia and
Alaska support either
the black bear or the grizzly, but rarely both. In regions where
both species coexist, they are divided by landscape gradients such as
age of forest, elevation and openness of land. Grizzly bears tend to
favor old forests with high productivity, higher elevations and more
open habitats compared with black bears.
The relationship between grizzly bears and other predators is mostly
one-sided; grizzly bears will approach feeding predators to steal
their kill. In general, the other species will leave the carcasses for
the bear to avoid competition or predation. Any parts of the carcass
left uneaten are scavenged by smaller animals.
give the bears a wide berth. Grizzlies have less competition with
cougars than with other predators, such as coyotes, wolves, and other
bears. When a grizzly descends on a cougar feeding on its kill, the
cougar usually gives way to the bear. When a cougar does stand its
ground, it will use its superior agility and its claws to harass the
bear, yet stay out of its reach until one of them gives up. Grizzly
bears occasionally kill cougars in disputes over kills. There have
been several accounts, primarily from the late 19th and early 20th
centuries, of cougars and grizzly bears killing each other in fights
to the death.
Coyotes, foxes, and wolverines are generally regarded as pests to the
grizzlies rather than competition, though they may compete for smaller
prey, such as ground squirrels and rabbits. All three will try to
scavenge whatever they can from the bears. Wolverines are aggressive
enough to occasionally persist until the bear finishes eating, leaving
more scraps than normal for the smaller animal. Packs of coyotes
have also displaced grizzly bears in disputes over kills.
The grizzly bear has several relationships with its ecosystem. One
such relationship is a mutualistic relationship with fleshy-fruit
bearing plants. After the grizzly consumes the fruit, the seeds are
excreted and thereby dispersed in a germinable condition. Some studies
have shown germination success is indeed increased as a result of
seeds being deposited along with nutrients in feces. This makes
grizzly bears important seed distributors in their habitats.
While foraging for tree roots, plant bulbs, or ground squirrels, bears
stir up the soil. This process not only helps grizzlies access their
food, but also increases species richness in alpine ecosystems. An
area that contains both bear digs and undisturbed land has greater
plant diversity than an area that contains just undisturbed land.
Along with increasing species richness, soil disturbance causes
nitrogen to be dug up from lower soil layers, and makes nitrogen more
readily available in the environment. An area that has been dug by the
grizzly bear has significantly more nitrogen than an undisturbed
Nitrogen cycling is not only facilitated by grizzlies digging for
food, it is also accomplished via their habit of carrying salmon
carcasses into surrounding forests. It has been found that spruce
tree (Picea glauca) foliage within 500 m (1,600 ft) of the
stream where the salmon have been obtained contains nitrogen
originating from salmon on which the bears preyed. These nitrogen
influxes to the forest are directly related to the presence of grizzly
bears and salmon.
Grizzlies directly regulate prey populations and also help prevent
overgrazing in forests by controlling the populations of other species
in the food chain. An experiment in
Grand Teton National Park
Grand Teton National Park in
Wyoming in the
United States showed removal of wolves and grizzly
bears caused populations of their herbivorous prey to increase.
This, in turn, changed the structure and density of plants in the
area, which decreased the population sizes of migratory birds.
This provides evidence grizzly bears represent a keystone predator,
having a major influence on the entire ecosystem they inhabit.
When grizzly bears fish for salmon along the coasts of
British Columbia, they often only eat the skin, brain and roe of the
fish. In doing so, they provide a food source for gulls, ravens, and
foxes, all of which eat salmon as well; this benefits both the bear
and the smaller predators.
Interaction with humans
Conflicts with humans
Bear attack and List of fatal bear attacks in North America
Native Americans fighting a Grizzly Bear, painting by George Catlin.
A rough and tumble with a grizzly by H.
Bullock Webster, watercolor
Grizzlies are considered more aggressive compared to black bears when
defending themselves and their offspring. Unlike the smaller
black bears, adult grizzlies do not climb trees well and respond to
danger by standing their ground and warding off their attackers.
Mothers defending cubs are the most prone to attacking, and are
responsible for 70% of humans killed by grizzlies.
Grizzly bears normally avoid contact with people. In spite of their
obvious physical advantage they rarely actively hunt humans. Most
grizzly bear attacks result from a bear that has been surprised at
very close range, especially if it has a supply of food to protect, or
female grizzlies protecting their offspring. A bear killing a
human in a national park may be killed to prevent its attacking
Hugh Glass being attacked by a grizzly bear, from an early newspaper
illustration of unknown origin
Exacerbating this is the fact that intensive human use of grizzly
habitat coincides with the seasonal movement of grizzly bears.
Increased human–bear interaction has created "problem bears": bears
adapted to human activities or habitat. Aversive conditioning
using rubber bullets, foul-tasting chemicals, or acoustic deterrent
devices attempt to condition bears to associate humans with
unpleasantness, but is ineffectual when bears have already learned to
positively associate humans with food. Such bears are
translocated or killed because they pose a threat to humans. The B.C.
government kills approximately 50 problem bears each year and
overall spends more than one million dollars annually to address bear
complaints, relocate bears and kill them.
Bear awareness programs have been developed by numerous towns in
British Columbia, Canada, to help prevent conflicts with both black
and grizzly bears. The main premise of these programs is to teach
humans to manage foods that attract bears. Keeping garbage securely
stored, harvesting fruit when ripe, securing livestock behind electric
fences, and storing pet food indoors are all measures promoted by bear
awareness programs. The fact that grizzly bears are less numerous and
even protected in some areas, means that preventing conflict with
grizzlies is especially important. Revelstoke,
British Columbia is a
community that demonstrates the success of this approach. In the ten
years preceding the development of a community education program in
Revelstoke, 16 grizzlies were destroyed and a further 107 were
relocated away from the town. An education program run by Revelstoke
Bear Aware was put in place in 1996. Since the program began just four
grizzlies have been eliminated and five have been relocated.
For back-country campers, hanging food between trees at a height
unreachable to bears is a common procedure, although some grizzlies
can climb and reach hanging food in other ways. An alternative to
hanging food is to use a bear canister.
Traveling in groups of six or more can significantly reduce the chance
of bear-related injuries while hiking in bear country.
Grizzly bears are especially dangerous because of the force of their
bite, which has been measured at over 8 megapascals (1160 psi). It has
been estimated that a bite from a grizzly could even crush a bowling
A grizzly in Denali National Park
The grizzly bear is listed as threatened in the contiguous United
States and endangered in parts of Canada. In May 2002, the Canadian
Species at Risk Act listed the Prairie population (Alberta,
Manitoba range) of grizzly bears as extirpated in
Canada. As of 2002, grizzly bears were listed as special concern
COSEWIC registry and considered threatened under the
U.S. Fish and Wildlife Service.
Within the United States, the U.S. Fish and Wildlife Service
concentrates its effort to restore grizzly bears in six recovery
areas. These are Northern Continental Divide (Montana), Yellowstone
(Montana, Wyoming, and Idaho), Cabinet-Yaak (
Montana and Idaho),
Montana and Idaho), Selkirk (
Idaho and Washington),
North Cascades (Washington). The grizzly population in these areas
is estimated at 750 in the Northern Continental Divide, 550 in
Yellowstone, 40 in the Yaak portion of the Cabinet-Yaak, and 15 in the
Cabinet portion (in northwestern Montana), 105 in Selkirk region of
Idaho, 10–20 in the North Cascades, and none currently in
Selway-Bitterroots, although there have been sightings. These are
estimates because bears move in and out of these areas, and it is
therefore impossible to conduct a precise count. In the recovery areas
that adjoin Canada, bears also move back and forth across the
The U.S. Fish and Wildlife Service claims the Cabinet-Yaak and Selkirk
areas are linked through British Columbia, a claim that is
disputed. U.S. and Canadian national parks, such as Banff
National Park, Yellowstone and Grand Teton, and Theodore Roosevelt
National Park are subject to laws and regulations designed to protect
A sign at a BC Park warns campers to hang food, garbage, and
toiletries out of reach of bears, or to use a secure bear cache.
On 9 January 2006, the
US Fish and Wildlife Service
US Fish and Wildlife Service proposed to remove
Yellowstone grizzlies from the list of threatened and protected
species. In March 2007, the U.S. Fish and Wildlife Service
"de-listed" the population, effectively removing Endangered
Species Act protections for grizzlies in the Yellowstone National Park
area. Several environmental organizations, including the NRDC, brought
a lawsuit against the federal government to relist the grizzly bear.
On 22 September 2009, U.S. District Judge
Donald W. Molloy
Donald W. Molloy reinstated
protection due to the decline of whitebark pine tree, whose nuts are
an important source of food for the bears. In 1996 the
International Union for Conservation of Nature moved the grizzly bear
to the lower risk "Least Concern" status on the IUCN Red
Farther north, in Alberta, Canada, intense
DNA hair-snagging studies
in 2000 showed the grizzly population to be increasing faster than
what it was formerly believed to be, and
Alberta Sustainable Resource
Development calculated a population of 841 bears. In 2002, the
Endangered Species Conservation Committee recommended that the Alberta
grizzly bear population be designated as threatened due to recent
estimates of grizzly bear mortality rates that indicated the
population was in decline. A recovery plan released by the provincial
government in March 2008 indicated the grizzly population is lower
than previously believed. In 2010, the provincial government
formally listed its population of about 700 grizzlies as
Canada consider the grizzly bear to a "special concern"
species, as it is particularly sensitive to human activities and
natural threats. In
Alberta and British Columbia, the species is
considered to be at risk. In 2008, it was estimated there were
16,014 grizzly bears in the
British Columbia population, which was
lower than previously estimated due to refinements in the population
Mexican grizzly bear
Mexican grizzly bear (Ursus arctos nelsoni) is extinct.
Drum or barrel trap, used to safely relocate bears, adjacent to a
Grand Teton National Park
Grand Teton National Park in Wyoming, United States
Conservation efforts have become an increasingly vital investment over
recent decades, as population numbers have dramatically declined.
Establishment of parks and protected areas are one of the main focuses
currently being tackled to help reestablish the low grizzly bear
population in British Columbia. One example of these efforts is the
Bear Sanctuary located along the north coast of
British Columbia; at 44,300 hectares (109,000 acres) in size, it is
composed of key habitat for this threatened species. Regulations such
as limited public access, as well as a strict no hunting policy, have
enabled this location to be a safe haven for local grizzlies in the
area. When choosing the location of a park focused on grizzly
bear conservation, factors such as habitat quality and connectivity to
other habitat patches are considered.
The Refuge for Endangered Wildlife located on
Grouse Mountain in
Vancouver is an example of a different type of conservation effort for
the diminishing grizzly bear population. The refuge is a five-acre
terrain which has functioned as a home for two orphaned grizzly bears
since 2001. The purpose of this refuge is to provide awareness
and education to the public about grizzly bears, as well as providing
an area for research and observation of this secluded species.
Another factor currently being taken into consideration when designing
conservation plans for future generations are anthropogenic barriers
in the form of urban development and roads. These elements are acting
as obstacles, causing fragmentation of the remaining grizzly bear
population habitat and prevention of gene flow between subpopulations
(for example, Banff National Park). This, in turn, is creating a
decline in genetic diversity, and therefore the overall fitness of the
general population is lowered. In light of these issues,
conservation plans often include migration corridors by way of long
strips of "park forest" to connect less developed areas, or by way of
tunnels and overpasses over busy roads. Using GPS collar
tracking, scientists can study whether or not these efforts are
actually making a positive contribution towards resolving the
problem. To date, most corridors are found to be infrequently
used, and thus genetic isolation is currently occurring, which can
result in inbreeding and therefore an increased frequency of
deleterious genes through genetic drift. Current data suggest
female grizzly bears are disproportionately less likely than males to
use these corridors, which can prevent mate access and decrease the
number of offspring.
In the United States, national efforts have been made since 1982 for
the recovery plan of grizzly bears. A lot of the efforts made
have been through different organizations efforts to educate the
public on grizzly bear safety, habits of grizzly bears and different
ways to reduce human-bear conflict. The Interagency Grizzly Bear
Recovery Committee is one of many organizations committed to the
recovery of grizzly bears in the lower 48 states. There are five
recovery zones for grizzly bears in the lower 48 states including the
North Cascades ecosystem in Washington state. The National Park
Service and U.S. Fish and Wildlife initiated the process of an
environmental impact statement that started in the fall of 2014 to
begin the recovery process of grizzly bears to the North Cascades
region. A final plan and environmental impact statement was
released in the spring of 2017 with a record of decision to
In early March 2016, the U.S. Fish and Wildlife Service proposed to
Endangered Species Act
Endangered Species Act protections from grizzly bears in and
around Yellowstone National Park. The population has risen from 136
bears in 1975 to an estimated 700 in 2017, and was "delisted" in June
In the past 20 years in Alaska, ecotourism has boomed. While many
people come to
Alaska to bear-hunt, the majority come to watch the
bears and observe their habits. Some of the best bear viewing in the
world occurs on coastal areas of the
Alaska Peninsula, including in
Lake Clark National Park and Preserve, Katmai National Park and
Preserve, and the
McNeil River State Game Sanctuary and Refuge. Here
bears gather in large numbers to feast on concentrated food sources,
including sedges in the salt marshes, clams in the nearby tidal flats,
salmon in the estuary streams, and berries on the neighboring
Bear catches a salmon at Brooks Falls
Katmai National Park and Preserve
Katmai National Park and Preserve is one of the best spots to view
brown bears. The bear population in Katmai is estimated at a healthy
2,100. The park is located on the Alaskan Peninsula about
480 km (300 mi) southwest of the city of Anchorage. At
Brooks Camp, a famous site exists where grizzlies can be seen catching
salmon from atop a platform—you can even view this online from a
cam. In coastal areas of the park, such as Hallo Bay, Geographic
Harbor, Swikshak Lagoon, American Creek, Big River, Kamishak River,
Savonoski River, Moraine Creek, Funnel Creek, Battle Creek, Nantuk
Creek, Kukak Bay, and Kaflia Bay you can often watch bears
fishing alongside wolves, eagles, and river otters. Coastal areas host
the highest population densities year round because there is a larger
variety of food sources available, but Brooks Camp hosts the highest
population (100 bears).
McNeil River State Game Sanctuary and Refuge, on the McNeil River,
is home to the greatest concentration of brown bears in the world. An
estimated 144 individual bears have been identified at the falls in a
single summer with as many as 74 at one time; 60 or more bears at
the falls is a frequent sight, and it is not uncommon to see 100 bears
at the falls throughout a single day. The
McNeil River State Game
Refuge, containing Chenik Lake and a smaller number of grizzly bears,
has been closed to grizzly hunting since 1995. All of the
Katmai-McNeil area is closed to hunting except for Katmai National
Preserve, where regulated legal hunting takes place. In all, the
Katmai-McNeil area has an estimated 2,500 grizzly bears.
Admiralty Island, in southeast Alaska, was known to early natives as
Xootsnoowú, meaning "fortress of bears," and is home to the densest
grizzly population in North America. An estimated 1600 grizzlies live
on the island, which itself is only 140 km (90 mi)
long. The best place to view grizzly bears in the island is
probably Pack Creek, in the Stan Price State Wildlife Sanctuary. 20 to
30 grizzlies can be observed at the creek at one time and like Brooks
Camp, visitors can watch bears from an above platform. Kodiak
Island, hence its name, is another good place to view bears. An
estimated 3,500 Kodiak grizzly bears inhabit the island, 2,300 of
these in the Kodiak National Wildlife Refuge. The O'Malley
River is considered the best place on
Kodiak Island to view grizzly
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Wikimedia Commons has media related to:
Ursus arctos horribilis (category)
Wikispecies has information related to Ursus arctos horribilis
Smithsonian National Museum of Natural History species account-Grizzly
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East Siberian brown bear (U. a. collaris)
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Tibetan blue bear (U. a. pruinosus)