Introducing babies to two year olds - how old is "old enough"

I am introducing my 5 new girls to a year old. The first meeting was between a fence and one of the babies tried pecking the year old! We decided to name her Sugar Ray (the boxer). The next meeting was in the run. I left the year old outside of it for about 15 minutes and then let her in. They were pretty good. I wouldn't leave them alone yet. The little ones are a month old.

 

I'm in a similar situation, they have had some contact,but I'm thinking that they should be close to the same size. At 8 weeks my BA 's{even though they are a large bird} are still half the size of my layers.

 

I have always gotten my chicks around the begining/middle of March, which, here in Colorado, winter is still well dug in. Once the weather gets nice and warm about the end of April-mid May, I start letting the little ones out to play and they are free to mingle with the others, or not (and vice versa) my chickens were always free ranged so the little ones always had room to escape any extreme meaness from the older birds, but this meathod worked very well for getting my birds aquainted with one another. Im not sure how well this would work with penned birds since the little nes dont have access to safe havens away from the older ones. What I would do is have their runs butted to each other so they can see and hear and expierience each other but cant get to them. introduce them for little bit at a time supervised and just kind of keep it gradual so that the older birds dont see it as a territory fight and try to keep the young birds out of their space.

 

The best age would be at about 12 weeks.