I am aabout to go get an australorp rooster and the guy said that it was with his chicks this spring. So i have 4 australorp hens that are a year old and nine assorted hens that are about 4 months old. I have 1 buff orphington rooster and i will seperate him with the two buff hens that would leave 12 hens for the baby rooster to live with. Will they pick on him. Should i seperate him till hes bigger?