Out of 7 mixed breed chicks I'm positive two are cockerels. Their fighting is getting worse, but they still don't hurt each other and often spend time together without fighting. They are about 8 weeks old, one is BR mix, the other poss. RIR/Cochin. He is heavier than the others, but about the same size. I know I will have to find a home for one of them, but have not decided which one. The RIR/Cochin is nicer to the others and very easy to handle, but so much bigger than 4 others. The BR is starting to show protective behaviors, but also pecks and grabs the others. He also seems to start most of the fighting. What age will they be able to hurt each other? Which one might be the best to keep? Out of the five others, one I'm pretty sure is a pullet. Three are poss. cochin banties and one silkie - these I'm not sure on sex yet. Thank you.
Once they get their spurs they'll be able to really hurt each other. I would separate them once you notice they're really fighting each other and doing damage. My guess would be that you have several weeks before that starts to happen, if not longer.
A while back I had three roosters and didn't have no problems. At first there was one big fight that I had to break up. But then they figured out there place in the flock order. They were still little fights some times but one would give up. If they get in a big fights it would be good to break them up once they get older. Good luck picking which one to keep.