I have a burried welded wire fence that is six feet high with a netting across the top. On Monday one chicken was killed with the breast meet eaten. So I shut them in again with just the window tipped in for venting. Nothing on Tuesday and this morning I had students come to me again and told me another chicken was dead out side the coop in the run. Now I think the hen was roosting on top of the window because there was poo on the outside window pane. One part of the fence there is a verticle wire gone (it came that way, didn't think anything could fit) and tracks out. Don't know what kind of prints, but a good size. Again breast meet gone. What can fit into a 5" x 5" square hole and jump up to knock the hen out the window, be quick enough to case it down and eat it. Two hens in three days is a little much for our students. This is a farm school where little kids help take care of the animals. This one stumps me.