This may sound like a stupid question and from me I should know. I had starter flock, lost most of them, but I was raising chicks from those chickens before the Lynx killed most of my adult chickens. As baby chicks, first week of age, I was able to tell the bays and girls apart. Because of the Lynx, I have been going without any new eggs since October and have been using store bought eggs. The reason is the survivors all except one broody hen are five months or younger. Also, because of the Lynx I've decided to keep the chicks to replace the ones lost. But now my "oldest" chicks are showing maturity. The five month old group were supposed to be all makes, but now I'm looking at some of them and I don't see the classic rooster tail. One is a rooster and he has made some crows. Their behavior says male but the broody hen did face off with some of them just like a rooster. This tells me that behavior alone is not going to tell me who's a male. So Is there a way to determine the sex of the nearly mature chickens? For the breed, I have Buff Orpingtons, one a Buff and Cinnamon cross (possibly female), Lavender orpington, and Ayam Cermani. However, I know one AC is a cockerel and the others are pullets.