We have 4 girls that are now 2 1/2 months old. They have been out in the coop for just about a month now. They sleep all piled up on top of eachother in 1 nest box. At first I thought they were cold but it has warmed up quiet a bit now and they still sleep in the pile. We have a nice roost running the length of the hen house. I have seen a couple of them perched upon it when I let them out in the morning, but I don't think that anyone has slept up there all night yet. Is this something that they will learn with age? Is something about the set up uncomfortable for them? I know they can't see well at night, maybe they don't see the roost pole? Is there anything I can do to encourage them to get up there?