Knowing when and how to introduce the older birds to my 9 week olds

[Morgk]

So idk if this is the right thread to post under but my chicks are 9 weeks old (5 of them) and my older hens are over 1 years old (3 of them) they see each other through fence and don’t have a problem but when I try to introduce my 3 into the 5, one of my older hens are mean and peck on them and chase them. What am I doing wrong? What did everybody else do to make it better?
I have a rooster chick that is in the same batch will he make sure that none of them are bullies or no? Kinda a stupid question

 

[FeatherstoneFrm]

Make sure the chicks have a safe place to get to where the older hens can't go. I had mine in a wire crate and when introducing I turned the crate on its side with the bottom now the back. The wire spacing in the bottom is big enough for the chicks to get through but not the hens. They could easily run behind and back in.
I also kept their food and water in the crate for a while so the hens didn't chase them away from food.
I doubt your male chick will do any protecting until he's mature.
With time and a safe place to run to. They will eventually work out the pecking order and get along.