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Trotting Moose, Grazing Bison
A pair of bull moose trot past grazing bison in Yellowstone National Park. At up to 7 feet high, moose are the tallest mammals in North America, while bison are the largest. Bull moose typically lose their antlers in early winter, but you can see the stumps remaining between their eyes and ears. The flap of skin hanging from their necks is called a bell and it is not known for sure what purpose it serves. The Lamar Valley where this was taken is located in the remote northeast corner of Yellowstone, along the only road that's kept open in the winter. It has been called the Serengeti of North America because of the wide variety of large wildlife that inhabit the valley. Grizzlies, black bears, moose, bison, elk, wolves, pronghorn antelope, bighorn sheep, coyotes, and red foxes can all be found here.