Lodges and Territories
Beavers live in homes called burrows or lodges. These are created by burrowing into banking where they will dig several chambers and entrances. Where the banking is not deep enough beavers will use harvested timber and mud to build on the top of the burrow, which is then referred to as a lodge.
Territory size is dependent on food availability and can range from 1 to 7 km. The whole family will work together to defend their territory from other beavers. The territory of an average beaver family will be around 3.6 km of linear wet-woodland habitat.
Lodges provide deadwood habitats which are important for invertebrates and their predators. Disused lodges are used by otters (Lutra lutra), small mammals and amphibians as breeding facilities and refugia.
Beavers will have several lodges or burrows within their territories, but will only use one of these during the winter. The living chamber will always be above water level, but the entrance will be under water.
To ensure that the entrance is under water beavers will sometimes have to build dams. This increases the depth of the water to submerge the entrance, allow movement under the ice during the winter and enables diving. High water levels also aid with access to food sources and easy transport of food and building materials. This building behaviour is instinctive and they improve with practice.