My sebastopols laid their first egg yesterday and my ducks have been laying since last winter. I gather up enough normal looking duck eggs and now there are goose eggs in the mix. Over the past week I have been noticing eggs that look like a duck/goose egg. They are textured like the goose eggs but about middle size compared to the two. They are way to big for egg cartons (even though duck eggs need to be forced in) and much smaller than the sebbie eggs. I have 12 mallard types (pekin, cayuga, swedish, call, mallard, runner) and a pair of sebastopol geese. I also have a big huge mule duck but I think its a boy (he regularly mates with the females). My hens sometimes mount other hens so could this just be a dominance behavior in the muscovy/mallard cross? I haven't seen an egg like this and my mule would be at the right age for starting to lay if it is a girl. What does everybody think? Duck on top, Mystery egg in the middle, Sebastopol on bottom Here is Bueler the muscovy/mallard cross (who I thought was a boy): AND this is "him" guarding the flock. These pictures were taken tonight (12/5/2012). I hope you can see the size difference between him and the others. That is a jumbo pekin right next to him. Bueler is huge! What do you all think? Could this be a girl and therefor the one laying my mystery eggs?