I have a 14 week old pullet/roo (this group identified it as a roo) whom I am trying to integrate into our flock of mature hens. No egg, no crowing. He/she was the only hatched chick from a broody hen in June. We have free ranged the chickens together for weeks without trouble and decided to integrate the youngster into the main coop.
I'm not clear as to what happened early. Did that broody hen raise him with the flock or did you keep them separated until later? To me it sounds like she raised him with the flock but he has been sleeping somewhere else. Now you want him sleeping in the main coop. I'll assume it's a he.
At 14 weeks he is a cockerel. He may or may not have had an attack of hormones, don't know if puberty has hit yet or not. Sometimes puberty hits earlier than that, sometimes it takes a few more months. Until they mature to a point where they can join the pecking order, if an immature chicken invades the personal space of a more mature chicken they may get pecked or worse. It doesn't matter if that immature chicken is male or female but some mature hens seem to really enjoy beating up on the boys even more than beating up on the girls. Instead of waiting for him to enter their personal space they attack anyway.
Since he has been free ranging with the flock he is integrated. They are not going out of their way to kill him or run him off. He knew enough to stay out of their way. Now it sounds like you are locking him in the coop at night and keeping him a a small run with them during the day. He doesn't have room to avoid them like he did before.
He is terrified of them. They won't let him sleep on the roosts with them so he looks for a safe place to sleep. That sounds like it's your nests. That is not unusual. That is a typical reason juvenile pullets and cockerels sleep in nests, the adults won't let them on the main roosts. I integrate juveniles all the time. I solved that problem by installing a juvenile roost, lower than the main roosts, horizontally separated so the adults can't peck them from their roost, and higher than the nests. I don't know if you have room to do that or not. If you try it you may need to physically move him to that new roost after dark to break him of the habit of sleeping in the nests. If you don't do that you can block the nests after the hens have laid for the day but before bedtime to force him to find another place to sleep. But open the nests so the hens can lay eggs the next morning. Or you can live with the messy nests.
During the day, as long as he is not getting hurt, he is not getting hurt. Is he scared? Yes, but he'll recover. When his hormones get to a certain point he'll try to mate with those hens. They may let him, that transition may go pretty smoothly. But it is likely it will get rough then. He may force them against their wills. They may fight back or they may try running away. He may chase them and force them, which can get rough.
That transition from him being lowest in the pecking order to flock master is usually pretty smooth with mine, but I have a lot of room. I think that helps. But sometimes it gets pretty rough, especially with the dominant hen, even with a lot of room. I think that is likely where you will have problems watching. As long as no ne gets hurt I let mine work their way through it but it can be hard to watch.
