We have our second flock of Buff Orppingtons now and they are about 9 weeks old. When we bought them they were supposed to be all female. As I've watched them I notice one is more aggressive and picks at the others. He or she also has a much larger comb then the others at this age. We also have Rode Island Reds and they all seem to be developed about the same. Keep waiting for crowing or some other sign of a rooster. Is there some simple way to tell at this age if this is a rooster we got by mistake or just a hen with ambition.