We have described beavers and presented pictures of them in our Busy Beavers gallery; the gallery below consists of pictures not of the animals themselves but of the result of their activities.
Cambium is the plant material just under the bark of the tree, and it is one of the beavers' preferred delicacies. At times they strip the bark from a tree not to fell it, but merely to access this delicious treat. Other times, it seems that the purpose of felling a tree is merely to ease the stripping of bark and eating of cambium as shown here:
We've also been meticulous enough to get a couple of before/after shots showing the process of felling a tree:
To be able to chew through a tree is spectacular enough, but doing so again and again results in dramatic changes to the river's edge.