The older ones may tolerate the younger ones when free ranging but being confined to a "smaller" area (coop) maybe another issue.
Absolutely!
We locked them together for a few hours in the morning for a couple of days, they all seemed ok when we let them out. They jump on the highest nest boxes if they want to get away also the roosts. They don’t follow then in the coop they just go to their “house.” ( the barn) I guess I’ll just try locking them in there all day and night with food and water and see what happens. I hope they will learn that is their house. There are three roosters with the 9 right now, if we culled them will the girls do better to integrate and learn better to go in the coop at night?
You'll need to make their 'old house' inaccessible, so they
can't go back in there. Removing the males would probably make everyone happier. Hopefully you have
plenty of space in the main coop/run for all other birds, integration works best with extra space....and a separate roost for the younger birds always helps.
Some of these tips might help.....
Integration Basics:
It's all about territory and resources(space/food/water).
Existing birds will almost always attack new ones to defend their resources.
Understanding chicken behaviors is essential to integrating new birds into your flock.
Confine new birds within sight but physically segregated from older/existing birds for several weeks, so they can see and get used to each other but not physically interact.
In adjacent runs, spread scratch grains along the dividing mesh, best if mesh is just big enough for birds to stick their head thru, so they get used to eating together.
The more space, the better. Birds will peck to establish dominance, the pecked bird needs space to get away. As long as there's no copious blood drawn and/or new bird is not trapped/pinned down and beaten unmercilessly, let them work it out. Every time you interfere or remove new birds, they'll have to start the pecking order thing all over again.
Multiple feed/water stations. Dominance issues are most often carried out over sustenance, more stations lessens the frequency of that issue.
Places for the new birds to hide 'out of line of sight'(but not a dead end trap) and/or up and away from any bully birds. Roosts, pallets or boards leaned up against walls or up on concrete blocks, old chairs tables, branches, logs, stumps out in the run can
really help. Lots of diversion and places to 'hide' instead of bare wide open run.