Hello all. My 3 australorp hens have slept on the roost in their coop since they moved outside as chicks. They are about 6 1/2 months old now. Suddenly, for the past week, every night when we go out to shut the chicken door between their run and henhouse, they are not inside like they used to be. Instead they are on the roost that is in the run. I can't figure out why! They have plenty of room in there, the poop board stays clean enough, and the roosts are at about the same height. Since it's been cold at night I've been leaving their window closed more, (They still have ventilation at the top of the henhouse) So I tried leaving their window open, in case they were staying out because they liked the cool air. They still didn't go in. They also do not seem afraid to go in at all during the day. They lay their eggs in their usual places, and come and go in and out throughout the day, so I do not think it's a predator problem. I'm getting tired of having to move full grown chickens into the coop every night! Any suggestions?