Stay at least 100 yards away from bears and wolves and at least 25 yards away from other large mammals like bison, elk, bighorn sheep, deer, moose and coyotes.
Wildlife is abundant throughout these two national parks. Go wildlife watching in their natural habitat in the areas they frequent most.
Bears climb high above timberline in Yellowstone National Park to feed on moths that come from farmland many miles away.
Didn't see a grizzly in Yellowstone? Head to Yellowstone Bear World to see grizzly and black bears, along with other animals like bison and moose.
Enjoy these photos of black bears, grizzly bears and cubs taken during the month of May in Yellowstone National Park.
Bears raid squirrel caches of stored whitebark pine nuts in the fall.
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Yellowstone bears are having problems finding chow. In addition to the loss of habitat by the rapid development occurring in the Yellowstone National Park ecosystem, bear researchers are concerned that several important food sources for bears are also in trouble.