I lost my rooster before I had a chance to really check fertility. Most of the eggs I incubated weren't fertile though, but my rooster was so lazy that I only saw him breeding a hen once!! I will be interested to see how mine do. I have read that fertility can be a problem, as I'm sure you well know, in the Wyandottes. I now have 4 wk old BLRW chicks and fertility in this line looks good. I hatched them from shipped eggs and of 18 only one wasn't fertile.
