Glad you asked, cause you got some good responses. When I have a broody mamma, she stays in that segregated area for about 10 days or so with her babies. These babies need to get strong in order to be able to move to safety of mamma belly if they are frightened and learn a little about life. The first two weeks of the mamma broody, she is very very protective of her chicks. If anyone comes near she will hurt them. My experience anyways. Beware the broody mamma. She is mean to anything but her own. My buff orpingtons are especially this way, the cochins could not give a hoot about anything. Two different ideas of what life is all about. And I am not kidding. My cochin mammas I can do anything with, beside, whatever, they just want to look after babies and don't worry about me or anything. It is interesting to say the least. Now the buffs, eeks, ya, even they put me runnin' and will attack.
After the two week or so period, the mamma will WANT to take the babies out to be wandering about. I have LOTS of room, so space is not an issue here. If I had space constraints as such, I would be very careful. I have seen your setup. There is a goodly amount of room, but leave that mamma separated for about that 2 week period. After that time you can remove the partition and she will mingle with the older chicks. They will learn to obey her and stay away, she will make sure of that. The other chicks are about 6 weeks old now? They will stay away from broody mamma when they mingle. By the time mamma neglects them, at about 5-6 weeks old, the babies will all be mingling together safely anyways, so that worry is done. Have a wonderful day, CynthiaM.