I found one of my hens dead this morning in a fox-proof run. My husband checked all round and found two small holes 3ft up from the ground in the chicken wire only big enough for a rat to squeeze through. We have overhead netting on the run so no chance of birds of prey entering. She was missing her head but otherwise undamaged. She was still warm so it can only have happened shortly before I found her at 8am. What sort of predator should we be on the look out for. My husband has already mended the holes. We live in a semi-rural area with lots of other houses nearby.