 Grizzlies migrating from the Complex range well out onto the Great Plains to the east, the only place this still occurs.Every species of mammal indigenous to the Northern Rockies still lives in this area and adjacent Glacier National Park, except bison and woodland caribou.Huge herds of elk, bighorn sheep, and mountain goat roam the region's rugged peaks, big river valleys, large meadows, and vast coniferous forests.