Why do Beavers Build Dams?

There are two kinds of beavers: the American and the European. The European beaver, found in Norway, Poland, Germany and France, lives in burrows.

But the American beaver builds a dam across a stream or lake to construct his home or lodge. The lodges are made of huge logs of trees.

The American beaver constructs solid dams and lodges because it has the mind of an expert engineer among all the creatures in the animal kingdom. And it is hard-working too. Moreover, building fortress like lodges and dams helps it escape unfriendly animals.

It is a fascinating process. The beaver first chooses a site towards the narrow end of a stream. Then it starts to fell trees. The animal stands on its hind legs and gnaws at the tree trunk with its sharp chisel-like teeth. The branches are cut off and the tree is then dragged or floated to the chosen site to dam the water. The tree acts like a wall.

The beaver uses broken branches, stones and mud to make the dam watertight. On this structure it builds a large dome-shaped lodge with two underwater entrances. One is a general entrance while the other entrance helps the beaver escape the animals that could harm it.

The beaver uses the lodge to store food as well as to raise its young. Since lakes and rivers freeze in winter, the lodge becomes a refuge from preying animals. Due to its underwater entrances the beaver can come and go as it pleases under the ice. Beaver dams also act as channels to control the flow of water in a stream or lake.

And that’s how the term eager beaver came about.