I've got 9 RIR 6 month old pullets and one rooster that was raised with them. I've got a 12 x 12 coop ... so pretty roomy. Yesterday I received the 12 new RIR chicks plus a surprise 7 additional free Rocks ... Today I put a volunteer chick out in the main coop ... alone. I thought if they kill this one I'll at least protect the others. After about 45 minutes the volunteer had received some pecks but none that brought blood. That's when I dug the tunnel and showed him the way back to the other chicks. It also showed all the chicks the way into the coop. I have it sheltered with an over turned scoop. What I'm seeing now ... about 5 hours later is the chicks are very curious about the main coop but stay near the tunnel and their food, water and heat. The older girls seem maybe a little puzzled by these new creatures. They seem to prefer outside ... free ranging more today. Obviously, I'm curious to see how this progresses. If all goes well I should be able to fully integrate in a few weeks. That would be great to be able to tear out the partitioned off area made just for the chicks.