Mountain Beaver (Aplodontia rufa
), most primitive living member of order RODENTIA
. Unlike true BEAVER
, mountain beaver has no close living relative. It resembles a tailless MUSKRAT
and has a thick-set, heavy body, small ears and eyes, forefeet equipped with long, strong, curved claws for digging, and dense, short, grizzled brown fur. Adult males average 850 g in weight, females 775 g. Mountain beavers breed once annually (Feb-Mar), have a gestation period of 28-30 days and bear 2-3 young.
Distribution and Habitat
Mountain beaver inhabit moist coniferous forests of the CASCADE MTS
from southwestern BC to central California. The mountain beaver digs a burrow system in damp, porous soil near streams. Burrow tunnels are 10-25 cm in diameter and 25-150 cm underground. Although several burrow systems may be adjacent, giving the appearance of a colony, the animals are by nature solitary.
Mountain beaver do not hibernate and, in winter, eat conifer needles, leaves, tender twigs and bark, often climbing 2.5 m up shrubs and trees to clip leaders and branches. In summer they prefer sword ferns, bracken, leaves and various herbaceous PLANTS
. They can cause extensive damage to young conifers and shrubs and by eating vegetable crops in gardens.
Mountain Beaver Distribution
Links to Other Sites
Canadian Biodiversity Website
A great information source for all budding biologists. Learn about biodiversity theory, natural history, and conservation issues. From McGill’s Redpath Museum.