North American river otters in Yellowstone National Park, Wyoming

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North American river otters in Yellowstone National Park, Wyoming

North American river otters can run on land at speeds of up to 15 miles per hour and have been documented sliding across snow and ice when a quick escape is required. But they’re incredibly well-suited to swimming, even when the winter brings the deep freeze to Yellowstone National Park. Their thick pelt and long, tapered body helps them glide through the water, propelled by their short legs and webbed feet. They’ll even swim below the surface of a frozen lake or river, staying submerged for nearly eight minutes before they have to find a hole in the ice and refill their lungs.