Facts About Beavers

FFacts On Tap Editorial Team Fact-checked Updated August 26, 2023 3 min read

Beavers are nature's engineers. With razor-sharp teeth and an instinct for construction, they reshape entire landscapes, building dams and lodges that create wetlands teeming with life.

From their waterproof fur to their record-breaking dams, here are 20 verified facts about these remarkable rodents.

Beavers are the second-largest rodents in the world, after the capybara.
An adult beaver typically weighs 35 to 65 pounds and measures 3 to 4 feet long, including its flat tail.
Beavers have a dense, waterproof undercoat beneath their outer fur that keeps them warm and dry in cold water.
They have webbed hind feet and a broad, flat, scaly tail that acts as a rudder while swimming and a prop while gnawing on land.
Beavers build dams and lodges out of mud, sticks, and branches, using their powerful teeth to fell trees.
A typical beaver dam is a few feet tall and under 50 feet long, though large dams can reach 10 feet tall and over 150 feet long.
The world's largest known beaver dam, in Alberta's Wood Buffalo National Park, stretches roughly 2,790 feet (about half a mile) and is visible in satellite imagery.
The pond behind a beaver dam creates a wetland habitat that supports fish, birds, amphibians, and insects.
Beavers are herbivores, feeding mainly on the bark, leaves, and twigs of trees such as aspen, willow, and birch.
Their front teeth never stop growing and are kept sharp and strong by constant gnawing, with an iron-rich coating that tints them orange.
Beavers can hold their breath underwater for up to 15 minutes.
They are mostly nocturnal and crepuscular, doing most of their building and foraging at dusk, dawn, and night.
Beavers are social animals that live in family groups called colonies, usually made up of a mated pair and their offspring from the past two years.
Wild beavers typically live 10 to 15 years, though some have lived over 20 years in captivity.
Beavers are native to North America and parts of Europe and Asia, home to the North American beaver and the Eurasian beaver respectively.
The beaver is an official symbol of Canada and appears on the Canadian nickel.
By building dams, beavers help raise water tables, reduce downstream flooding, and recharge groundwater.
Beaver ponds and wetlands also filter pollutants, trap sediment, and help prevent erosion along waterways.
Beavers communicate through vocalizations, tail slapping on the water, and scent marking with a musky secretion called castoreum.
A beaver's tail slap on the water is a warning signal that can be heard by other beavers over 100 yards away.
Beavers are generally monogamous and often mate with the same partner for life.
Baby beavers, called kits, are usually born in spring and can swim within hours of birth.

Frequently asked questions

How do beavers build dams?

Beavers gnaw down trees and branches with their strong, ever-growing teeth, then pile the wood along with mud and rocks across a stream to slow the water flow and create a pond around their lodge.

What do beavers eat?

Beavers are herbivores that eat the bark, leaves, and twigs of trees like willow, aspen, and birch, along with aquatic plants.

Why are beavers important for the ecosystem?

By damming streams, beavers create wetlands that recharge groundwater, reduce downstream flooding, filter pollutants, and provide habitat for fish, waterfowl, and other wildlife.

Do beavers mate for life?

Beavers are generally monogamous and often stay with the same mate for life, raising several litters of kits together over the years.

What is the lifespan of a beaver?

Beavers typically live 10 to 15 years in the wild, though some individuals in captivity have lived past 20 years.

Where are beavers found?

The North American beaver lives across most of the United States and Canada, while the closely related Eurasian beaver is found in parts of Europe and Asia.

Sources & further reading

Reviewed by the Facts On Tap Editorial Team

We write every article to be genuinely fun — and genuinely true. Each fact is checked against reputable sources before it goes live. Spotted something off? Tell us and read our fact-check policy.

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