Physical characteristics and behaviour

Beavers are well-known for two particular characteristics: teeth and tails. The beaver’s long buck teeth help it chew on tree trunks and branches to gather wood for building its home, called a lodge, a dry living area which it accesses through underwater entrances and ramps. To protect this lodge from being washed away the beaver will build a dam, which slows down the water flowing in the streams it inhabits. 

Beavers, like the impressive architects they are, build their dams in slow-flowing streams, using a combination of sticks, logs, mud and other natural debris. Their strong tails are used to pat mud into place on the dams, keeping the entire structure sound and secure. Beavers also use their tails as propellers when swimming, and to prop themselves up when standing or sitting on land.

Beavers are excellent swimmers and can even chew underwater without getting water in their lungs, thanks to a special flap at the back of their mouths. Beavers have clear membranes over their eyes that help them to see underwater, like goggles. They can also hold their breath for up to 20 minutes while working underwater! 

A beaver’s teeth never stop growing over the course of their lifetime. In order to keep them at a healthy size, beavers grind their upper and lower teeth against each other, filing them down. Chewing on wood all day long also helps keep their teeth strong and at a safe size. 

As the colder months approach, the water around the lodge, along with the layer of mud and grass over it, will freeze, keeping out predators like lynx and wolves. Otherwise, if a beaver ever feels threatened, it will slap its tail on the surface of the water to warn other beavers in the area, then it will dive deep underwater to stay safe.

Diet

Their diet consists of new tree bark on certain trees (birch, aspen, willow, alder and cottonwood), twigs, leaves and pond vegetation. 

Habitat and distribution

Beavers can be found in lakes and streams all over Canada. The world’s longest beaver dam is found in Alberta’s Wood Buffalo National Park and is almost 800 metres in length. The average dam is only about 100 metres in length!