Well I bought the rubber eggs and left two of them in the hen house all day yesterday whilst I was at work. When I came home the first thing I did was check on them and we have some good news - two eggs survived the day but the bad news is one still didn't!
I took the rubber eggs out for the night and left them next to the hen house which was a mistake for two reasons. Firstly is that when I walked to the hen house to let the girls out this morning one of the rubber eggs was missing! I mean what the hell! Secondly there was another eaten egg in the house! So today I'm going to leave the eggs in the house all day and all night to see if that helps any more. I'll keep you posted!