Why do beavers build dams?

   Beavers build dams so that they will have safe homes close to a supply of food in winter. In the pond that forms behind their dam, the father and mother beaver put together a hut. It looks like a jumble of sticks and mud, but it is quite strong. It has a good dry room inside and the entrance is hidden under water. A beaver family — the father, mother and several young ones called kits — live together in the house.
   Even in winter when the woods are deep in snow and the pond is frozen over, beavers usually have plenty of food. They eat the bark from tree branches and bushes which they have cut and then anchored in the mud at the bottom of the pond.