Introduction of new chicks to the Old Flock

[Naztrain]

Wow, it's been a few years since I've been on this site...

So, my grandparents bought 9 "day old" pullets (3 golden sex-links, 1 black sex-link, 1 black Australorp, 1 Barred Rock, and 3 Americaunas) around Easter time, making them about 5 weeks old. I have an old flock (hatched in 2006) that consists of 4 Buff Orpingtons (one rooster) and a RIR hen. The chicks are in a brooder inside the coop, visible to the old flock, and have been in there for about 2 weeks.

At what point should I feel safe pulling the chicks out of the brooder? I've heard a few times "When they're the same size as the adults" but I feel like I recall that my Orpingtons took nearly 4 months to be full-grown.

 

[alxw]

All flocks have a pecking order but buffs are usually pretty docile. I don't take my new chicks out from under the heat lamp in my brooder until they are around 5 weeks old, which then they should be used to a temperature of around 70 degrees and no longer need the heat lamp. I think after seeing each other for one month and a week they should be acclimated to each other. When you put them in a pen just sit back and watch until you feel comfortable that the new babies will be safe. If you have a mean hen that will pick on the babies separate her for a week or two from the whole group and try reintroducing her to the flock again. Sometimes that solves my hens bullying problems when I introduce new members to the flock. Good luck!