Most folks see bears as denizens of forests and mountains. On the whole that is true, except for grizzly and polar bears, both are quite happy to also live out in the wide-open spaces of the prairies, northern tundra and arctic areas. In fact, one of the ancestral natural habitats of the grizzly bear is the great plains of North America. Before white settlers came into the west, thousands of grizzlies occupied areas from the Alberta foothills all the way to the Manitoba-Ontario border and south to Mexico. The official scientific name of the grizzly is the North American Brown Bear and reference is made to a variety of sub-species dependent mostly on where they are located such as the Alaska Kodiak bear, the Mexican grizzly, etc... The unofficial name 'grizzly' was applied by early explorers and refers to their appearance.
One ponders what the grizzly bear survived on whilst living on the plains during the past millennia, as food sources would seem either sparse or hard to catch. Much of the plains were occupied by swift grazing animals like bison, elk, deer and antelope, all of whom could outrun any bear in the open. Lucky for bears they are omnivores and can survive by eating almost anything like vegetation, bugs, fish, worms and rodents. They are also significant scavengers of carrion of any kind, which the vast herds of millions of grazing mammals provided on a steady basis. Bears are also robust opportunists and rely on other predators to their hunting for them. A key to their survival on the plains was their relationship with their arch rival, the prairie wolf. Bears have the uncanny ability to sniff out and locate wolf kills for many miles around. They would then chase wolves off their hard-won food supply. Only a large aggressive wolf pack had the ability to keep a hungry grizzly off their kill.
With the arrival of white settlers the fate of both the prairie wolf and prairie grizzly bear was sealed and both were all but exterminated from the Canadian plains by the 1900s. Governments on both sides of the border put bounties on wolves which wiped them out by the 1920s, that saw a big food source loss for grizzlies. Then the bison disappeared and another food supply was lost. Then cultivation and cattle grazing took over much of the traditional grizzly habitat. The final straw was the vulnerability of a large somewhat slow moving mammal on the open prairie, it made it an easy target for hunters on horses with long range rifles. The prairie bear basically disappeared within a fifty year period. There was no stopping the extermination of prairie bears anywhere near human habitation as humans, being a prey species, have a visceral psychological primal fear of such a large threatening predator. By the early 1900s grizzly bears were confined to mountains and deep forested areas mostly in the Alberta Rockies, and BC.
The cousin of the grizzly, the more numerous Black Bear, never was a significant resident of the plains but thrived on the fringes in forested areas. An area that they still occupy to this day in considerable numbers. The two bear varieties are not happy neighbours and generally avoid contact with each other. In addition humans have a somewhat more sympathetic view of black bears, seeing them as less aggressive and more of a nuisance animal, that perception probably saved them from extermination in many areas. That causes one to ponder why then do government agencies and wildlife groups spend so much money, time and energy trying to increase grizzly numbers – isn't one bear variety enough in the wild environment. I suspect it has more to do with psychology and the business end of conservation. For reasons that escape me grizzly bears are seen as some sort of iconic species in the wilderness that are critical to ecological stability. I would dispute that as there is little evidence that a wilderness area collapses with the absence of a grizzly bear, the presence of black bears would seem to mitigate such concerns.
However, from a conservation business aspect grizzlies do have a role. They create jobs for government conservation employees and a host of related services. University researchers are kept busy with government grants for investigating grizzly behaviour of every kind. And of course wildlife groups have a continuing iconic symbol to support their endless fund raising campaigns. It would seem the grizzly bear has created its own people-sustaining industry.