Existing "adult" flock: 10 hens (ages 1-3 yrs) and 1 BCM rooster (1 yr old) Baby flocks: Mixed group of 11 week olds and mixed group of 1 week olds. We definitely want to add a second rooster to our adult flock, which right now consists of 10 hens/1 rooster but by the end of summer will be probably 16-20 hens. We are considering keeping a Brahma rooster who is in our group of 11 week olds. At what age is it appropriate to add our second rooster? Right now he is 11 weeks old and nearly as big as our smallest adult hen.