I have had beaver denning in the bank on my 13 acre pond since I bought the place 12 years ago and they cause very little trouble. About 2/3 of the bank is in woods, and they get most of their needs met there. I wrap a single layer of hog-wire around the lower trunk of trees that I especially want to protect on the rest of the bank, and the beavers don't bother them.

The only other difficulty is that every winter, when water is flowing out the spillway, the beavers begin a dam across it. After several years of pulling the dam out with a box blade, I made a very helpful discovery. If you pull out a short section (1-2 ft.) of the very early dam�before they bring in the bigger sticks�(I keep a potato rake next to the spillway with which to accomplish this) and don't even bother to toss the debris away, the beavers will concentrate on repairing the hole with new material and will wait for the water level to rise before adding any new material to the rest. They will not re-use sticks which are pulled below or a little to the side of their dam, and it is easy to keep them redoing the same work all winter.
Lou