Soft bark is the main food for a beaver. Swimming Information Beavers can swim underwater for 15 minutes. They can do that because they have very big lungs. Their tails are used as a rudder. If they turn their tail to the right the beaver will go left.
Beavers have noses and ears that close when the beaver is in the water.
Lodge, Dam, and Canals Beavers' houses are called a lodge. A lodge can be 10 to 20 feet around and 6 to 8 feet above the water. The lodge can have 2 to 5 entrances and they open up under water so they can get inside the lodge under the winter ice. Having the entrances underwater protects them from predators. The lodge is made from sticks, logs, mud, and dry leaves and is built on a river bank or a pond made by a dam.