Why Do Beavers Build Dams?

It’s super impressive that beavers can create massive dams — big enough to stop the flow of a river — all by themselves with the things they find in their environment.

But why do beavers build dams, exactly? It actually may not be for quite the reason you think.

A dam is a structure beavers build in their river habitats. According to the National Wildlife Federation, these resourceful rodents create dams using trees, mud, branches and sticks. Beavers actually use these materials to block the flow of water and create their own little pond in the river they live in.

Beavers build dams using their long, powerful teeth. They can chew through tree trunks, which causes the trees to fall into the water and block the flow of the river.

Beavers will also gather nearby branches in their mouths, adding them to their dams to make them bigger and sturdier.

The reason beavers build dams is for protection. While beavers don’t actually live within the dam structure itself, dams do act as a protective barrier to keep predators from reaching their homes.

While beavers don’t live in dams specifically, they do live in structures called lodges. These are dome-shaped homes made out of branches, mud, grass or moss.

Beaver lodges have underwater entrances, but the actual living area is above the water’s surface inside the domes.

According to LiveScience, beavers live in freshwater habitats — like rivers, streams, ponds and lakes — all over North America. (They aren’t typically found in northern Canada or the deserts in the southwest United States.)

Some beavers also live in parts of Europe and Asia.

Now that you know all about how and why beavers build dams, it’s super easy to be impressed by these adorable little engineers.