Silkie Rooster separating hens

[Pooders5]

I have a year old silkie rooster that was living with two redx hens until last month i got two silkie hens. He now only protects and feeds and breeds the two silkie hens and keeps the other two hens away from them . He also will chase and keep the two larger hens in the nesting boxes while in the coop.
Has anyone seen this behavour before?
Its like he only likes his own breed.
I have three dorking pullets to add in later, they are separated right now .

 

[chrissynemetz]

I've never seen this happen before? My chickens don't seem to notice the difference in breeds?

 

[DellaMyDarling]

You could try giving him an isolation treatment for a few days. Always best if the isolation crate is still near/with the flock.

Did he mate the previous hens?
Does he stand guard over nesting hens or is he truly just making them run off?

 

[Pooders5]

He did try to mate with the larger but he is smaller...there were 4 hens but i lost two just after getting him. He runs them to the nesting box and stands guard between them and the two silkie hens. They only eat and drink once he has settled down next to his two girls