The beaver is renowned for the unique ability to fell relatively large trees with its robust front teeth. Not only does this give it greater access to food in the form of leaves, twigs and bark, but it also provides the raw materials needed for damming waterways and building its lodge (3) (6). The dam provides an area of still, open water where the lodge can be conveniently constructed and protected from terrestrial predators (7). The lodge is essentially a pile of mud and sticks, which usually has one or more underwater entrances, with an inner chamber that rises above the surface of the water (3) (6).
Secretive and nocturnal, the beaver typically rises at sundown and returns to the lodge at sunrise. During spring and summer, non-woody plants form the bulk of this herbivore’s diet but over autumn and winter, tree and shrubs, such as aspen and willow, are increasingly consumed (5) (6). During the autumn, populations in the north often build a cache of branches and logs underwater near the lodge, to be eaten over the winter (6).
The social life of the beaver is built around the colony, which typically consists of an adult pair and two to six young (5) (6). Longterm monogamy is unusual among mammals but beaver pairs generally remain together until one adult dies. Mating takes place once a year, usually around January and February, with three to four kits (young beavers) being born in late spring, following a gestation period of around 107 days (2) (3) (6). The young kits are weaned within two months, but require a long period (up to two years) within the family in order to learn the varied skills that are essential for independent life (2) (5).