Not yet. If you have a mature flock, you'll want to raise your chicks in a brooder at first. Then once they are mature enough to be introduced to the coop, you will still want to keep them separated from your existing flock. Once your chicks reach a mature size that is close to the size of your flock, you would need to place the new additions and the existing flock in an area where they can see and hear each other, yet are separated, for at least two weeks. After two weeks you would be able to mix them together. It's best to do this around dusk when they are more docile.
There will be normal pecking order to follow after. This is the best gradual introduction you can make because if you were to place them without the introductory period there could be dire consequences or injury due to the smaller birds being cornered by larger birds.
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