Beaver and beaver dams

Creatures of habit, like most wildlife, beaver are quite predictable.  If you are breaching dams with the intent in placing traps of any type, it is best to keep the holes "small but noisy."  Beaver respond well to the sound of running water, but large holes require a big response, large branches, logs etc.  Traps are much more apt to get sprung and or buried into the dam itself if the hole is a gusher.  A smaller hole will produce a more a surgical response by a beaver, commensurate to the size of the hole in the form of a clump of grass or a little mud.

When dams are breached with large openings by a landowner or have large leaks due to heavy rains or water merely overflows a dam, beaver will leave the dam alone and simply not work on it.  Where there has been a major leak, a beaver will wait for the water to drop and stabilize before rebuilding the dam.  Beaver will quickly patch a small hole.

If you can find a location where the leaking water will drop several inches, splash onto a flat rock or gurgle around a stick, all the better.   Noisy is good.

Holes in a dam will repaired with new material.  If you remove sticks from a dam and place them behind or beside the dam, they will not be used by the beaver.  Beaver will pick up new brush from the pond and pack it back into the dam if you put those sticks in the water in front of the dam.  At times beaver may rearrange a few sticks, but they will do little to disturb the actual structure.  Once the dam is built, the material in the dam will remain there forever.  Beaver inherently know that a leaking dam will need more material.  They don't want to weaken or disturb sticks that are already in place, just add to it and strengthen what is there.