Beaver (Castor canadensis)

Beavers are common and are found throughout Nova Scotia. As Canada's national emblem, the beaver serves as a model for hard work and perseverance. When beavers move into a small stream, they build a dam that creates a pond deep enough to keep it from freezing to the bottom.

The lodge is the beaver's fortress and are 1.8 to 2.7 m high and 3 to 6 m in diameter built of logs, sticks, mud, and rocks on the bottom of a pond with a living area set above the water level. The covering of mud makes the lodge weather tight. In winter, the mud freezes hard and prevents predators from getting in.

Beavers store their winter supply of food under water. They eat the bark of trembling aspens, willows and white birch, as well as leaves, twigs and buds.

The paddle-shaped tail is the beaver's most notable body part. Not only does it serve as a rudder when they swim, they use it to prop themselves up when standing, and as a lever when dragging logs. A slap of the tail on water also signals danger to other beavers.

Beavers have many characteristics that help them adapt to life in water. The beaver's coat has two layers: an outer protective layer of coarse guard hairs and a dense under layer of fine hair that insulates them. Fur-lined lips close behind their front teeth (incisors) allowing them to clasp on tree branches and roots while under water. When they dive, their nose and ears have valves that close tightly to keep the water out. Besides their normal eyelids, beavers have an inner transparent eyelid that protects the eye when they go under water. They normally can stay under water for 3 to 4 minutes but if necessary, can extend that time to 15 minutes. They have webbed hind feet which enable them to swim up to 800 m under water without surfacing for air.

Their weight varies with age, sex and the season, but most adults weight 20 kg. They mate in January and February, with 1 to 8 young born from late April to late June.