American Beaver

Castor canadensis

Click to view a larger image. Click to view a larger image. mammal mammal

American Beaver
Image: Steve Hillebrand
Source: US Fish and Wildlife Service

Museum specimen featured in the Wild exhibition
Source: Museum Victoria

Type: mammal

American Beaver American Beaver
Image: Steve Hillebrand
Source: US Fish and Wildlife Service

Conservation Status

Secure Vulnerable Endangered Extinct  ]

Historically, American Beavers were hunted for their pelts, which were turned into hats. Whole populations were wiped out, but strict control of the fur trade and reintroduction efforts have allowed numbers to recover. The most serious threat is now pollution of aquatic enviromnents. American Beavers are considered a pest in some areas, because they damage ornamental trees and their dams cause local flooding.



American Beavers are herbivores.

They eat tree bark, aquatic vegetation, roots, twigs and leaves.


American Beaver relative size depiction as described below

Size relative to a cat and a woman.

11–30 kg
body 80–120 cm, tail 25–50 cm
30–60 cm at shoulder

Amazing American Beavers

American Beavers are the largest rodents in North America. They live in lakes, streams and rivers and build extraordinary homes called lodges from sticks, mud and moss. They construct a network of dams to ensure the entrance to the lodge is hidden underwater, making it inaccessable to predators. This building behaviour reduces erosion around waterways and creates a diversity of wetland habitats in which many other species live.

Family groups of up to eight individuals live together in the lodges. Pairs mate for life and their offspring, called kits, remain in the family lodge until two years old. Kits are born fully furred and can swim within 24 hours. The older offspring assist their parents to build the lodge and to rear the youngest litter.

American Beavers are well adapted to aquatic life, with their dense, waterproof fur, webbed hind feet and a thick layer of fat for insulation. They use their large, flattened tails to propel and steer themselves when swimming, and to signal danger by slapping against the water surface. Powerful teeth and a large skull allow American Beavers to eat a diet of tough, woody plant material.

Did You Know?

American Beavers

  • build dams that dramatically change local landscapes
  • have bright orange teeth that grow continuously throughout their lives
  • have microorganisms in their gut to help digest cellulose


American Beaver distribution map

American Beavers are found in Canada, North America and the north of Mexico; also introduced in Finland and Russia. They live in freshwater aquatic environments.


Other animals from the Nearctic

Wood DuckAmerican Black BearGreat Horned OwlWolverine