Winter in America has its power, bringing with it sub-zero temperatures, bitter windstorms, and food shortages. Some animals retreat to nests and burrows to wait until spring arrives, while others make long journeys to warmer climes. But the strongest will persevere and endure. Wolves and pumas use their sensitive snouts to track their prey wherever they need to go. River otters and bald eagles hunt in the ice, and bearded puffins plunge into the snow for a bite. Every morsel can mean the difference between life and death.