Ducks attacking chickens

[Kevomxracer]

So my pekin ducks have been very aggressive with my chickens and they will charge the chickens from behind and bite at there tail feathers or grab there neck feathers. And I have to go over and shooo them away. But they are always trying to do it. It's mainly the male pekin duck. But it's been getting worse lately. The ducks are never aggressive toward me. They actually run away from me and like never let me touch them. Any help?

 

[Tubbys Lil Farm]

I would like to help...but my male Jumbo Pekin does that same thing to my chickens. He does not seem to hurt them, he just herds them away from the duck pool and scratch that I put in the yard. This has been going on for several months, before it seemed that he would put up with the chickens being in his space. He is about 11 month old.