Another idea is to use a tripod and a remote camera. Another thing that I am going to be doing is using my GOPRO. They will be stuck on the wall or somewhere else and since they won't be moving or any lights or noise they will be doing what ever and I will catch them in the act without even being there.... A lot of ways. Furthermore, if they play with the camera, it won't move and they can't hurt it.
For anyone who wants to play around with this idea checkout
HTTP://WWW.GOPRO.COM. I have 2 of them, and they will do a lot more than take pictures. I mounted one on one of my RC planes... Crashed and destroyed the plane, and the camera was still recording during the entire event and still working today without a scratch.
See the video, if the camera can take this, it can take anything a Savannah can trough at it. It is hard to tell, but the plane hit the ground at about 30 MPH.