This is what I was told by someone who has hatched and raised for many decades. So far about a 98% accuracy rate. When they are a few weeks old, the ones whose tail feathers stick out are hens. My last hatch (6/27) it looked like all hens and one was questionnable. About 6 months later - first eggs from the two thought to be hens. That questionnable one, Milo, did lay. Milo was the runt and didn't grow as quickly, so his - whoops...her tail feathers were slower. I definetly looks like the one on right is a hen and he other???
