Why would our female sit a clutch with no drake?

[RedfogsFlock]

Our mama duck is sitting on a clutch of 16 eggs, BUT

1. They are not fertile at all, cuz we haven't had a drake till recently. She had 13 of the eggs before we got our drake.

2. Will she eventually kick out the eggs if they're not any good?

I felt bad for her so I gave her some of my fertile chicken eggs.
I didn't think they would sit a clutch if they weren't fertile, but she is CRAZY broody! I'm scared to take them, she may eat me!

LOL

 

[GrannySue]

I felt so sorry for my broody chicken that I gave her fertile duck eggs to sit on!

Now the world is evened out.

 

[nettie]

Simple answer, lol... Hormones! I have 6 female ducks who all take turns sitting on eggs.... Even though we don't have a male... silly ducks