Two dead RIR - what is doing it???

[Julz2u]

I found one of my RIR dead in the corner of the coop on Sunday. A hole about the size of a baseball was missing from her side. There was no sign of struggle. Today I found another RIR in the coop at the exact same spot with the same size hole in her and the eggs were missing. It seems that whatever is killing my girls is doing it when they are on the nest. Does anybody have any ideas what could be doing this. Its happening during the day. When I left for work this morning, everyone was accounted for.

 

[jenjscott]

Rats or skunks is my guess.