Between 1800 and 1975, grizzly bear populations in the lower 48 states decreased from estimates of more than 100,000 to less than 1,000. The grizzly was eliminated from much of the west by the late 1800's. As mountainous areas were settled, development contributed to an increase in human-caused mortality. Livestock depredation control, habitat deterioration, commercial trapping, unregulated hunting and the perception that grizzlies threatened human life were leading causes of the animal's decline.
The U.S. Fish and Wildlife Service listed the grizzly bear as a threatened species under the Endangered Species Act in 1975, meaning it is considered likely to become endangered ("endangered" means a species is considered in danger of extinction within all or a significant portion of its range).
The degradation of habitat due to rural or recreational development, road building, and energy and mineral exploration is one of the many of the current threats to the survival of grizzly bears. Habitat destruction in valley bottoms and riparian areas is particularly harmful to grizzlies because they use these "corridors" to travel from one area to another when they are searching for food. Some private landowners and companies are trying to help grizzlies by voluntarily protecting grizzly corridors.
Some grizzly bears are accidentally killed by hunters who mistake them for black bears, which can be legal game. But the biggest threat to the grizzly is human-caused mortality. Grizzlies become habituated to humans because of what biologists call "attractants," which include garbage pet foods, livestock carcasses, and improper camping practices. This can eventually lead to conflicts between people and bears - not only in populated areas of the grizzly's range but also in back-country recreation sites.
Today, in the lower 48 states, grizzlies can be found in small portions of Wyoming , Montana , Idaho and Washington . There are approximately 350 grizzlies living in the northwestern Montana Rockies, about 350-400 in or around Yellowstone National Park, about 10 in the Selkirk Mountains in northern Idaho and northeast Washington, another 15 or so in the Cabinet-Yaak ecosystem in northern Idaho and western Montana, and perhaps 10 or more in the North Cascades of upper Washington state.
In Alaska , where they are called brown bears, they are estimated to number more than 30,000. There are also populations of grizzlies in Alberta and British Columbia . One goal of the agency which manages grizzly bears, the U.S. Fish and Wildlife Service, to restore the grizzly bear in the Lower 48 states, calls for recovering grizzly populations in all of the ecosystems that are known to have suitable habitat.
The grizzly bear recovery effort has been met with some successes thus far. Grizzlies in the Greater Yellowstone Ecosystem are coming close to the recovery target but still suffer from too many yearly mortalities. Grizzlies in the NCDE have nearly reached recovery goals, and with dedicated science projects intended to record the minimum population,
recovery goals may be met soon - unless, once again, human-caused mortality continues to be in excess of what the population can tolerate (27 grizzlies were killed in the NCDE in 1998).
Successes have been largely due to a cooperative effort among several organizations, including the Interagency Grizzly Bear Committee (IGBC), private landowners and conservation groups. Established in 1983, the IGBC includes the U.S. Forest Service; National Park Service; Bureau of Land Management; state agencies in Montana, Wyoming, Idaho and Washington; Canadian wildlife management agencies; and Native American Tribes.