In fall and winter they feed on woody items such as the bark and cambium of trees. The cambium is the underside of the bark that keeps the tree alive. The wood of the tree has no nutritional value for the beaver. Beavers are nocturnal animals. Nocturnal means active at night.
Beavers become active at sunset and end their activity at sunrise.
Since beavers are not usually seen during the day, their presence can be identified by the dams and lodges that they build. The home of a beaver is called a lodge . Dams are built to stop the flow of water causing an area to flood. Two ways of beaver communication is by scent and using their tail. Scent is used to communicate to other beavers that an area is occupied.