Source: Produced for Teachers' Domain
NARRATOR: Have you ever seen a dam? This is the Hoover Dam. It holds back the Colorado River. The water trapped on one side of the dam forms a lake. There is only one animal besides humans that can build a dam...beavers.
In springtime, beavers build their dams. They build them out of logs, branches, stones and mud...across rivers, streams and shallow ponds. The dams hold back running water and in a few weeks, there is a deep new pond.
Once the pond is about three feet deep, beavers build a lodge to live in, constructing a room with underwater doors and tunnels. Inside the lodge, they stay safe from enemies such as otters and people. They snack on water plants and roots along the edges or bottom of the pond. Mostly they eat leaves, twigs and tree bark.
Have you ever been near a pond and heard a loud crack? It was probably a beaver, smacking the water with its wide, flat tail to warn others of danger. Their webbed feet and strong tail make beavers very fast swimmers...but clumsy and slow-moving on land.
Beavers have to come out of the water to groom themselves. They have a special gland that makes oil. They spread the oil over their fur to make them waterproof. Their oily fur keeps them warm and dry.
Beavers are nocturnal. They do most of their work at night. They use their sharp teeth to cut down trees a little at a time, working their way around the tree. Once the tree is down, a beaver often eats some of the leaves, twigs and bark and then cuts and hauls the branches into the water.
In fall, the heavy work of dam repair begins. Beavers fix their dam and build it higher to make the water deeper. If the pond is not deep enough, it could freeze to the bottom and trap the beavers inside their lodge. Once they have finished packing the dam with sticks and sealing it with mud, the beavers are ready for winter.
During the winter, beavers eat the branches and leaves they have gathered near their lodge. They eat the bark, turning the branches like corn on the cob.
Many animals build their own nests, tunnels and other types of homes. But a beaver's dam does more than keep the beaver safe in its lodge.
Beaver dams change the landscape dramatically, just like human dams, creating new habitats for many kinds of plants and animals. Dragonflies, turtles...raccoons, ducks, frogs...otters and heron are just some of the animals that benefit from the ponds beavers create.
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