a couple of things:
It will probably take weeks before you can integrate the new chickens. I can't tell if you have them fenced off from the old flock or not, but you should - chicken wire is fine - and when they start to settle down, throw treats at the fence line so both sets of chickens are coming to the fence for the treats - gets them close with something to think about besides getting each other.
In my experience, the rooster might be the biggest problem - they seem more set on keeping newcomers away from everything.
Where the chunk of feathers and meat is missing,you might want to spray blue kote - it stains the skin/wound with purple and makes it less likely for the chickens to peck each other. Chickens will peck at open wounds and can actually kill a chicken with an open wound from the pecking.
When you think they are easing up on each other, and it is better to wait a long long time, because it is harder to fix it if you jump the gun and the integration goes badly......then switch quarters. Take the old flock, move it to the new flock's coop and space, and take the new flock and move it to the old flock's coop and space. Leave them that way for a few days, and then at night do two things: first remove the barrier separating the two flocks, and 2nd, make as many changes as possible to the run space. Move everything around and add some barriers that break up the space. The barriers can be anything - logs, bales of hay, cardboard boxes weighted so they don't blow over, tires, garbage cans......what you want to do is to make so many changes that when they come out they are totally confused, and also that there are places to hide behind - out of sight is out of mind for chickens. Then, be sure to be there when letting them out in the morning to observe and intervene if you need to. There will be squabbling - you will have to let it happen. If it seems bad, distract them by throwing scratch. Make sure you have multiple water and feed stations. Watch to make sure everyone gets to eat and drink. Its good to plan this day for a day when you can be home.
I have had a rooster that would not accept the newcomers, and I finally had to cull the rooster. Hopefully that won't happen for you.
Next time, you might want to think about quarantine before you add chickens to your flock. You can search byc and you will find a ton of info about the reasons why and how to do it.
Good luck!
