Well I looked at one of my chicken books.It says skunk -possible skunk smell,baby chicks killed, abdomens eaten. egg eater- leaves shells behind. Opossum- abdomen eaten/missing, bodies are mauled, eaten at the vent. egg eater leaves behind the shells. Racoon- crops and heads eaten, eats eggs shells left behind. Hope this helps, sorry for your loss. Seal every crack in the coop