Male dewlap attacking my male call ducks

[duey dewlap]

I have a 1 year old male dewlap who has lived quietly with my call ducks for almost a full year/ Up until the last few months. He has started picking on the males & 1 has died from his injuries. I've researched & all I keep hearing is that they are a quiet docile bird(which I agree) does anyone know what I should do? Should I get some more geese for him to have around or just another one only female? Would really appreciate some help Thanks

 

[CelticOaksFarm]

he is a LARGE gander, if he is the only gander he needs others to be with, and needs to be kept separate from the ducks at all times or risk injures/death to another. A call duck is no match for any goose who is upset, or hormonal.