I'd like to try motion sensors. But with a lumbering 150lb Newfoundland, an 80lb German Shepard, and a Jack Russel Terrier constantly chasing the two cats around I'm afraid our house is a lost cause. The birds are gone now, but they used to add to the ruckus by flying around daring the cats to catch them. I think motion detectors are out until our zoo quiets down! On the other hand, nobody sneaks into our house without causing a tornado of activity and barking. No silent entry here!