So I have a flock of 7 females, two ducks (khaki Campbell and Pekin) and 4 black stars and one buff orphington. I found my first egg today and the mystery began. I believe it was from my khaki Campbell but am still new at this. The egg was about the size size of medium chicken egg from the store. The only reason I think it might be one of my ducks is the fact that the egg was hard to crack. I would appreciate any help I can get. This is the only photo I took....hunger ruined the rest 
