I currently have a great flock, my first flock and one coop. They all free range. I want to get another "flock" of birds this spring, but I will need another coop. Can the new flock be trained to go into their coop, the existing flock still go back to their coop? I'm hoping they can all free range together, the additional coop would just be for space. How you have added more chickens with new coop? I don't use runs, they just coop themselves up at night.