Last spring we had a problem with a nocturnal predator that was beheading our birds. It would take away the head, but nothing else. We tried everything; traps, sitting up all night with a shotgun, loud noise, but nothing worked. Our flock was reduced by about 90%. Finally it dawned on me. Take the s.o.b. out of its comfort zone. We bought one of these, and set it up in the pen; 500 watts of light on a timer. Problem solved! We only use one of the lights at a time that way if one burns out we just turn the other on. The light has no effect on the girls laying or our electric bill. Winner!