I have 35 chickens that all mingle together as they free range. My younger birds go to one coop to roost, and my older birds to a different coop to roost. I have 6 Australorpes and 2 EE in my younger flock and they do fine together. In fact, they all do well together for the most part. The main squabbles happen with the birds within the same breed as they are working for pecking order dominance.