The males are heavier than the females and can weigh up to 1, pounds kilograms. A large female will weigh up to pounds kilograms. Grizzly bears once roamed throughout the entire western United States south into Mexico, including the Great Plains and along rivers in desert habitats.
Control actions and habitat loss extirpated them from 98 percent of their original habitat in the U. A large population of grizzly bears lives inland in Alaska and northern Canada. Thanks to conservation efforts since about , grizzly bears are recovering well in Yellowstone and elsewhere in the Northern Rockies and are even beginning to recolonize prairie habitats along the Rocky Mountain Front in Montana.
Grizzly bears can be found in woodlands, forests, alpine meadows, and prairies. In many habitats they prefer riparian areas along rivers and streams.
Grizzly bears are omnivores. The most commonly eaten kinds of plants are fleshy roots, fruits, berries, grasses, and forbs.
If grizzly bears are on the hunt, their prey can include fish especially salmon , rodents like ground squirrels, carrion, and hoofed animals like moose , elk, caribou, and deer. They are especially good at catching the young of these hoofed species.
Grizzly bears can also target domestic animals like cattle and sheep and cause economically important losses for some ranchers. The National Wildlife Federation has a program on National Forest lands surrounding Yellowstone Park to prevent attacks on domestic livestock by purchasing the grazing allotments from ranchers. Grizzly bears use sounds, movement, and smells to communicate.
They growl, moan, or grunt, especially when females are communicating with their young or during mating season when male bears can fight each other fiercely for the opportunity to mate with receptive females.
Grizzly bears also rub their bodies on trees to scratch and to let other bears know they are there. Winter can be very tough for many species of wildlife, because the season brings harsh weather and little food. Grizzly bears hibernate in warm dens during the winter to minimize energy expenditure at a time when natural foods are not available and to permit their tiny young to be born in a warm and secure environment.
Throughout the summer and autumn, grizzly bears build up fat reserves by consuming as much food as they can find. In late fall or winter, the bears find a hillside and dig a hole to serve as their winter den.
When inside the den, grizzly bears slow down their heart rate, reduce their temperature and metabolic activity, and live off stored fat reserves. Pregnant females give birth in the dens and nurse their cubs until they are large enough to venture outside in the spring as snow melts and new food become available. Depending on the length of the winter season, grizzly bears can stay in their dens for up to seven months.
Grizzly bear hibernation is not as deep of a sleep as some other hibernators, like bats or ground squirrels, and they will quickly wake up when disturbed. Females with newborn cubs are the last to leave their dens in the spring. Females with older cubs emerge earlier and solitary females and males are the first to exit dens in the spring.
Pregnant females are the first to enter dens in the fall followed by females with cubs; solitary males enter dens the latest. Grizzly bears begin to look for mates in the spring and early summer. Females can mate with more than one male during her breeding season. Females give birth during this winter rest, often to twins.
Grizzly bears are powerful, top-of-the-food-chain predators , yet much of their diet consists of nuts, berries, fruit, leaves, and roots.
Bears also eat other animals , from rodents to moose. Despite their impressive size, grizzlies have been clocked running at 30 miles an hour. They can be dangerous to humans, particularly if surprised or if humans come between a mother and her cubs.
Grizzlies once lived in much of western North America and even roamed the Great Plains. These animals need a lot of space—their home range can encompass up to square miles —so their ideal habitat is one that is isolated from development and has plenty of food and places to dig their dens. Though European settlement gradually eliminated the bears from much of their original habitat, grizzly populations can still be found in parts of Wyoming, Montana, Idaho, and Washington State.
Many grizzlies also still roam the wilds of Canada and Alaska, where hunters pursue them as big game trophies. At its peak, the grizzly population numbered more than 50, Aggressive hunting in the early 20th century also threatened the survival of the grizzly bear.
By the s and s, these bears had been reduced to less than 2 percent of their historical range. In the s, it was estimated that there were only to remaining in the wild. In , grizzly bears were listed as threatened under the U. Endangered Species Act. Today, grizzlies are considered a conservation success story. Ever since they gained protections under the U. Endangered Species Act, the population of grizzly bears has grown. The U. Fish and Wildlife Service established recovery zones for the bears and set out to improve relationships between humans and bears by educating the public about these animals and establishing programs to reimburse ranchers for livestock bears killed.
Now there are more than five times the number of grizzlies than there were in —and about 1, to 1, in the contiguous U. While the U. Fish and Wildlife Service has tried to delist grizzly bears twice, both attempts have been blocked. In , the second attempt was blocked in federal courts over concerns about the lack of genetic diversity among this subspecies whose various populations live so far apart. Fish and Wildlife Service announces a final plan to introduce at least 25 grizzlies into the Bitterroot Ecosystem of Montana and Idaho.
The reintroduction plan had faced major opposition from the states, including a lawsuit from the Idaho governor. When listed, an estimated to bears lived in the GYE. By , that number is higher than Fish and Wildlife Service says this means grizzlies in the Yellowstone area have recovered, and they propose removing endangered species protections for the GYE bears. Following nearly , comments from the public, the U. Conservation and tribal groups quickly file suit.
In a page decision, a federal judge in Missoula puts Yellowstone-area grizzlies back on the endangered species list. The judge also says the conservation strategy in place to maintain protection of bears is largely unenforceable and inadequate. More than bears are estimated to live in the NCDE, and the grizzly population has been growing consistently for years.
Data on recreation, industry, road use, and other factors in this year will prove crucial later, as environmental advocates and wildlife managers spar over what sort of habitat is necessary for a growing grizzly population. It serves as a baseline of habitat data for a time in which bears thrived. On a hike in the high mountains, year-old Joe Sebille snaps a picture of a grizzly on a hillside. Scientists verify the photo is of a living grizzly bear, likely foraging for food to help it through the winter.
The last verified sighting of a grizzly was in This is the first photograph in the more than 50 years of a living member of the species in the North Cascades. A three-judge panel for the U. Fish and Wildlife Service erroneously removed federal protections for Greater Yellowstone bears. Tallman in his decision. The court says the whitebark pine decline does pose a threat to grizzlies. Grizzly bears continue expansion from core habitat in the Northern Continental Divide Ecosystem , venturing east of the Rocky Mountain Front.
In a Hutterite colony near Valier, Montana, two collared grizzlies are found dead. Members of the colony claim the bears died of exhaustion as they were chased away. A female grizzly, nicknamed Ethyl, makes a long journey that takes her from close to Canada, near Missoula, through the Bitterroots, and deep into Idaho.
State officials are optimistic that the bear shows evidence that grizzlies and humans can coexist without conflict. The National Park Service announces it will start an environmental analysis that will serve as a first step in reintroducing grizzlies to the North Cascades Ecosystem. This step will take at least three years, and will involve extensive public input. More than 3, people comment on federal plans to reintroduce grizzlies into the North Cascades.
The document comes in at over 1, pages long, and includes passionate thoughts from grizzly advocates, people fearful of living with grizzlies, and just about every perspective in between. Officials expect to finalize plans by the end of Signatories cite a rich history of cultural and spiritual significance.
Over the next two years, more than tribes will sign the treaty. While mountain biking outside Glacier National Park, Forest Service law enforcement officer Brad Treat collided with a grizzly bear as he turned a blind corner.
Surprised, the bear mauled and killed Treat. The tragedy brings attention to the need for proper precautions for all forms of recreation — not just hiking — in bear country. These precautions include carrying bear spray , making noise and reducing speed in low-visibility areas. It came at the same time as state and federal measures that could expand mountain bike access in bear country. Court of Appeals for the District of Columbia rules that Great Lakes gray wolves should remain under federal protection.
The court says segmenting populations in this way is legally possible, but was improperly done in this case. Interior Secretary Ryan Zinke announces delisting of Yellowstone-area grizzlies. An estimated bears exist in the ecosystem, and their range has more than doubled since the s.
Conservation groups and tribes file suit, citing a plethora of concerns. But more bears are finding their way near homes and into fields and stockyards. Locals worry about grizzly impacts on livestock, grain, and the safety of their families.
If one female is killed in the core habitat, no other grizzlies in the area can be hunted. Idaho proposes a hunt for one bear. Montana refrains from a grizzly hunt this year. The hunts in Idaho and Wyoming will begin on September 1. In total, up to 23 bears could be taken. After legal challenges to its document, the USFWS releases a supplement to the Recovery Strategy that identifies criteria in habitat necessary for bears to flourish.
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