Drake beating up duck

[Golden Brahma 64]

so kind of weird situation.
My drake (call duck) keeps beating up my other call duck yet he likes the bigger ducks and tries to mate with them. He treats my call duck as if she were another Drake but I’m 110% sure ITS NOT. I’ve tried separating and all but it doesn’t work. I guess he like the bigger ones ehh

 

[Quackers3211]

I had a problem similar to that except my drake preferred the smaller one. I ended up rehoming bc he would not quit picking on it. All is good now though.