The grizzly bear is a North American subspecies of the brown bear (Ursus arctos). This omnivore is distinguished by a large shoulder hump and long claws. The current distribution of these bears shows geographic isolation, with populations now concentrated in the vast northern wilderness areas of North America.
Global Range and Historical Context
The brown bear is found across Eurasia and North America, but the grizzly is the population inhabiting North America. Historically, the grizzly bear’s range stretched from Alaska and western Canada down to central Mexico, and from the Pacific Coast eastward to the Great Plains. Before European settlement, roughly 50,000 grizzly bears roamed the western contiguous United States alone.
This wide distribution contracted over two centuries due to human expansion, as bears were viewed as a threat to livestock and safety. Persecution, combined with habitat loss and fragmentation, led to the elimination of the species from approximately 98% of its original range in the lower 48 states. Today, the remaining populations are isolated remnants, primarily surviving in remote mountainous regions and northern territories.
North America’s Population Strongholds
The majority of North America’s grizzly bears reside in Alaska and western Canada, where populations are the largest and most stable. Alaska is home to the highest population, estimated to be over 30,000 individuals. These bears are widespread across the state, thriving in diverse habitats from the tundra to coastal areas, where the seasonal abundance of salmon provides a rich food source. Regions like the Alaska Peninsula are known for their dense populations of coastal brown bears.
Canada maintains a large population, with an estimated 20,000 to 29,000 bears occupying the western provinces and territories. British Columbia serves as the primary Canadian stronghold, hosting more than half of the country’s grizzlies, with estimates reaching up to 16,000 individuals. Numbers also inhabit the Yukon and Northwest Territories, where human impact is minimal and tracts of wilderness remain intact. These northern populations benefit from connected landscapes, which allow for greater genetic diversity and stability compared to their southern counterparts.
Where Grizzly Bears Live in the Lower 48 States
In the contiguous United States, grizzly bears are restricted to small, geographically isolated populations in the Northern Rocky Mountains, resulting from conservation efforts under the Endangered Species Act. The U.S. Fish and Wildlife Service has identified six Grizzly Bear Recovery Ecosystems, though only four currently support established populations.
Greater Yellowstone Ecosystem
The largest population is found in the Greater Yellowstone Ecosystem, encompassing parts of Wyoming, Montana, and Idaho, which supports approximately 1,000 bears.
Northern Continental Divide Ecosystem
A comparable number, about 1,000 bears, resides in the Northern Continental Divide Ecosystem, centered around Glacier National Park and the Bob Marshall Wilderness Complex in Montana.
Smaller Ecosystems
The remaining two populations are much smaller and more fragmented. The Cabinet-Yaak Ecosystem in northwestern Montana and northern Idaho supports around 65 bears. The Selkirk Mountains Ecosystem in northern Idaho and Washington is estimated to hold approximately 100 individuals. These geographically distinct groups rely on continued management to maintain numbers and genetic health.