I'd go with coon. I had one tear up my flock after finding a way in (my yellow lab, which usually guards the chickens was sick and not doing much at the time). I found a few with heads torn off. I'll second the "use your girl as bait" advice. I figured she'd already died, and I couldn't even eat her, so I did the best thing I could. I won't detail what happened to the racoons but there are four less now, and I figure for every one I catch there's ten I didn't.