Male runner ducks pecking each others necks

[Runnerduck123]

Hi…
I have 2 male runner ducks I’ve had them from ducklings I’ve had them for 3 years now. They share a house and have the run of the whole garden in the day time and are put in their house at night. My question is every year at a certain time they get aggressive and peck each others necks we’ve tried separating them in the day to try stop this then they are fine again and we put them back together anyway one of them is more aggressive this time and has made the other ones neck bleed a lot. After a while they are fine again just when you think the other one has healed and scabbed over it happens again.

 

[springvalley123]

It's mating season. There must be a duck (which is a female) around, maybe nearby. Even if you are sure there isn't a female nearby that you're aware of, you need to separate them or it'll keep happening.