How to Re introduce 3 mama’s with their combined 45 chicks to the flock?

[Hovering Mama]

I had 3 mama’s brood at the same time. I’ve kept them in separate chick runs, but the mama’s seem to want to attack each other. The non mothering hens and fathering roosters could care less, but the new mom’s aren’t having it! Not sure when to or how to reintroduce the 3 mama’s and their combined 45 new chicks! I was thinking one set at a time. ? Suggestions? Has anyone introduced more than one mama and their chicks before? It’s my first time with brooding hens and I haven’t read anywhere that anyone’s had this experience with more than one mama. The mama’s were raised together, were nesting neighbors, but since their chicks hatched, now get very aggressive when they are able to get near each other. Hence, why they each have separate chick runs now.
Thanks for your knowledge!

 

[NatJ]

Since they are in separate runs now: are they next to each other, and able to see each other? If yes, that can help them get used to seeing another hen nearby without being able to chase her away.

If you have large amounts of space, I might try turning them all loose at once and watch what happens. They will probably just spread out, with each hen wanting 10 to 20 feet of distance from all other chickens.

The problem with introducing them one at a time is that the first hen may claim the space as "hers," and cause trouble when you add the next one.

I'm not sure what the best method is, but a few details that can make any method work better:
--have multiple sources of feed and water, so no hen can claim all the food/water spots
--have places that chicks can go but hens cannot, so all chicks can escape any hen that tries to bully them. Options include laying some pallets on the floor, or dividing off an area with large wire mesh so chicks can go through but hens cannot, or leaning some boards against the wall so chicks can run behind them like a tunnel (leave both ends open so they won't get trapped), and so forth.

This article has some ideas that may help:
https://themodernhomestead.us/working-with-broody-hens-let-mama-do-it-part-five/
(I have not personally tried most of what that article talks about, so I can't be positive how well they work.)