Loosing neck feathers

[MallardDuckling]

I've noticed one of my girls looks like she is loosing some feathers on the side of her neck.

Not sure what it could be from. I do have a male, but I haven't seen him pick on her at all. He tends to just follow them or lead them.

Any suggestions on what it could be from, what I need to keep my eyes open for and how to get her feathers to grow back?

She's not bald on her neck, just thinning out.

 

[Baylor]

I am guessing it is your male drake!

 

[Kevin565]

It's probably from mating or molting.

 

[MallardDuckling]

Those were the only 2 ideas I could come up with too.