My wife and I bought a straight run of black australorps and we have 9 left (well, one is a mystery breed). We aren't allowed to keep roosters here, but I don't think the rule is enforced because I hear roosters all the time. We're thinking of keeping one cockerel for breeding and protecting the flock from anything that somehow manages to get into the chicken run. We want to keep our most docile rooster (so it wont harass us when we enter the run) and then sell or barter the rest. Right now the chicks are about 4.5 weeks old and there is one that we believe is a boy because he has a red comb and already has waddles. He is always challenging others because I guess he wants to be at the top of the pecking order. Is it too early to know if he will be an aggressive rooster down the line that we should get rid of? At what age can we tell the personalities of roosters?