<P> Beaver dams are dams built by beavers to provide ponds as protection against predators such as coyotes , wolves , and bears , and to provide easy access to food during winter . These structures modify the natural environment in such a way that the overall ecosystem builds upon the change , making beavers a keystone species . Beavers work at night and are prolific builders , carrying mud and stones with their fore - paws and timber between their teeth . </P>
<P> Beaver dams are dams built by beavers to provide ponds as protection against predators such as coyotes , wolves , and bears , and to provide easy access to food during winter . These structures modify the natural environment in such a way that the overall ecosystem builds upon the change , making beavers a keystone species . Beavers work at night and are prolific builders , carrying mud and stones with their fore - paws and timber between their teeth . </P>
how does a beaver 's dam changed the environment
how does a beaver 's dam changed the environment
the overall ecosystem builds upon the change
the overall ecosystem builds upon the change