Description

Avery large, bulky rodent, with rounded head and small, rounded ears. Dark brown fur is fine and soft. Scaly tail large, black, horizontally flattened, and paddle-shaped. Large, black, webbed hindfoot has 5 toes, with inner 2 nails cleft. Eyes and ears small. Large, dark orange incisors. L 3-4'; T 11 3/4"-17 1/2"; Wt usually 44-60 lb, but sometimes up to 86 lb.

Similar Species

Muskrat and Nutria are much smaller and have slender tails.

Breeding

Mates late January-late February; 1-8 kits (usually 4 or 5) born after gestation of 4 months.

Sign

Alarm signal: Slaps tail on water loudly enough to be heard at a considerable distance. Dams of woven sticks, reeds, branches, and saplings, caulked with mud. Dome-like lodges in water, 6' high or higher, up to 40' wide. Scent mounds: heaps of mud, sticks, and sedges or grass, up to 1' high and 3' wide, where beaver deposits scent from anal glands, apparently to mark family territory. Logs and twigs peeled where bark is eaten. Felled trees and gnawed tree trunks; gnawing's at considerable heights made when beavers stands on surface of deep winter snow; successive gnawing's, made when snow is at different levels, may produce totem pole effect.

Scat: Seldom deposited on land; distinctive oval pellets, 1" long or longer and almost as thick, of coarse, sawdust-like material that decomposes quickly; may contain undigested pieces of bark.

Tracks: Distinctive when not obliterated by wide drag mark of tail. Usually only 3 or 4 of the 5 toes print, leaving wide, splay-toed track 3" long. Webbed hindfeet leave fan-shaped track often more than 5" wide at widest part, at least twice as long as forefeet; webbing usually shows in soft mud.

Habitat

Rivers, streams, marshes, lakes, and ponds.

Other

Active throughout the year, the American Beaver is primarily nocturnal and most likely to be observed in the evening. Beavers living along a river generally make burrows with an underwater entrance in the riverbank; these are known as bank beavers.