67 / 116
First they use their large, sharp front teeth to cut down trees by the
stream. They cut off the branches and drag them into the stream. They
put mud and rocks on the branches to hold them in place. Then they
add more branches and mud.
The beavers are making a dam. They keep adding to the dam until it
reaches all the way across the stream. Water is trapped to form a pond.
The beavers then build their lodge.
So what about the plants and other animals living in the stream
environment? Some of them benefit from the beaver’s work. Others
can’t live there anymore. The beavers cut down the trees for food and
building material. This means less shade. When water floods the land
around the stream, the grasses, bushes, and trees living there die. Insects,
snakes, squirrels, and all the other land animals have to move out. When
beavers build a pond, the animals that live on the land by the stream are
forced to move, and the plants growing along the shore die.
It’s different for the aquatic plants and animals. Fish and frogs have a
lot more room to live. Aquatic plants, like cattails and water lilies, thrive.
Some aquatic insects, like dragonflies and mosquitoes, benefit from the
changed environment. Aquatic plants and animals grow and reproduce
to take advantage of the larger environment created by the beavers.
A pond created by a beaver dam
built across a stream
67