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01

Beaver Dams

Beavers are brown, furry mammals that live in lakes and rivers. In order to survive in this habitat, beavers build dams. They do this by using their large front teeth to cut down trees and then pile up wood to block the flow of water. Doing this causes deep ponds to form behind the dam. This gives beavers a place to hide as they can dive into the deep water. It also provides a place for beavers to live and store their food.

Beavers live in lodges that they build in the middle of ponds that are created by their dams. These lodges are made of mud, sticks, and logs. The entrance to these lodges is underwater. The inside of a beaver lodge is small compared to the outside because beavers need thick walls to protect them from other animals.

Trees are very important to beavers. They not only provide wood for shelter, but they also provide food. The diet of the beaver includes bark, leaves, and roots.

Beavers cause changes to the environment that can be both positive and negative. Ponds that are built by beavers provide new wetland habitats for fish, frogs, and water birds. These wetlands also slow soil erosion and keep more water in the ground. This allows plants to grow.

On the other hand, however, beavers also destroy trees that are the homes of birds and other animals. Beaver dams also slow down the flow of water in streams. This causes silt to build up. Dams can also flood the land behind them.

Word List

lodge : a dome-shaped home that beavers build from mud, sticks, and logs

shelter : a kind of home, protection from cold, wind, etc.

silt : small particles of soil deposited by water

wetland : a habitat where shallow water covers most of the ground

You Practice

I. Fill in the blanks—Complete the following sentences with words from the reading.

1) Beavers use their _______________________ to cut down trees.

2) Beavers live in ______________________.

3) Beavers eat __________, ____________, and _____________.

4) The walls of a beaver lodge are very ______________.

5) Wood provides _______________ and _____________ for beavers.

II. Complete the chart about positive and negative effects of beaver dams.

Positive Effects

1)

2)

Negative Effects

1)

2)

III. Read these sentences carefully. Write Yes or No for each one.

____1) Beavers eat some parts of a tree.

____2) Beavers enter their lodge from underwater.

____3) Beaver lodges can be bad for other animals.

____4) A deep pond can provide safety for beavers.

____5) Beaver dams allow the water in streams to flow faster OU/QumJha0wfeqlU35igGsNeZnIzbYE29BlzFF/kbeknd8d8Yy5XN4Y9xfGL/b0R

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