Hmmm...my chickens (1 rooster and 5 hens) are at 18 months and have always used the roost. We have two roosts of equal height and they recently started fighting over who got to sit where. Now over the past week several of the hens have taken to using the nests instead of the roost and I assume it is because the rooster and the dominant hen are giving them too much grief. Every night this week when I go out to lock them in, I lift each hen out of the nest and put her back on the roost. There is a a lot of commotion but as long as I am there talking to them they all try to behave. I know, though, that when I leave the hen house and peek through the window they start arguing again. Bad little chickens. I guess I will just keep moving them from the nest and back to the roost until they settle back to normal. I am wondering if this behavior is a result of them being in moulting season??? Do they feel less secure in defending themselves on the roost? Any thoughts?