Rooster attack on hen

[JonBonPoultry]

Long time lurker of this site so I know I've come to the right place for advice. I've got a Silkie rooster, Jon, who's never been any trouble however the last couple of days he's been singling out one hen and attacking her. He will chase her down and start beating on her or he will mate with her first then start kicking and jumping on her. Why is he doing this and how to I get him to knock it off? I have recently had some changes to my setup. I have 2 coops (green and blue, Jon lives in blue) with separate runs divided by a fence. I had 2 troublemakers in the green coop so got rid of them as well as my 2nd rooster over a week ago, leaving 3 hens. I've now opened up the runs to all chooks. Since doing this Jon is attacking Hen Solo from the green coop. Have I perhaps not given everyone time to adjust to the missing chooks? Or is something else going on? Why is Jon being so nasty?!

 

[Folly's place]

Welcome!
Is she being injured? How old is everyone? Are there places for birds to avoid each other, and not be seen?
You may have to separate him for a while, and see what happens. The changes made recently will certainly affect flock dynamics, and apparently not for the better right now.
Mary

 

[JonBonPoultry]

There's no injuries at this point. I'm not sure how old they are but I've had them for a little over a year and they were mature when I got them. There's plenty of space and hiding spots. I think maybe I'll keep the chooks on their respective sides for another week or so then try again?