The beaver is North America’s largest rodent and is built for life in the water. Adults can be up to four feet long and weigh over 60 pounds. The beaver has webbed hind feet and a large, flat, nearly hairless tail. It uses its tail to help maintain its balance when it is gnawing on trees. It will also slap its tail against the water to signal danger or to warn away predators. The beaver has short front legs with heavy claws. Their rear legs are longer, and their webbed feet help propel them through the water when they are swimming. When the beaver is under water, its nose and ears close up, and a special membrane covers its eyes.