My guess would be rats. My computer recently died and I lost some of my pictures. I have put cameras in my coops and did have a rat infested coop that I renovated. This is what I used. I only found a couple of dead rats that I disposed of. The others I believe went into their tunnels I noticed around the coops. There is a a little window above the bait in my rat bait boxes that only the rats and mice can get to that can be checked often and replaced as needed. The bait that came with the bait box didn't work all that well for me so I bought other bait that worked well. I had to replace the baits less and less until there came a point of hardly ever changing them. We are rural. I think rats will show up sooner or later. We have some hawks around that sit in trees nearby and prey on field mice now and then. This is the bait stations I use but there are several other designs.
Was it in their feeder or where you store the feed?
