Fertile?

[sbrown]

I just collected these eggs and don't think they are fertile. I had two roos over breeding my hens . Gave one away a few months ago and haven't visually seen the other one breed a hen since? Do the roos slow down in winter as well? I was hoping to put some eggs in the incubator soon.

 

[Wyandottes7]

Its hard to tell from the photo, but at least the egg on the lower left looks fertile. To be certain, try incubating a few. It can be difficult to tell for sure whether an egg is fertile or not, just by looking at the yolk.