When are eggs fertile?

[Quack head]

I have five Appleyards three young females (four months old +/-) one older female 1 year old and a drake 1 year old. I see the drake mate with all the females, or at least try. The older female has brooded, I assume, a couple of times this winter. On a nest and hisses at me when I come in the house. After a few days she is back in the yard like nothing is happening. Two fake eggs in the nest and we pick up the others she lays.

When should I leave the eggs in the nest? Also, should I let the duck hatch her own eggs? Should I isolate her from the rest of the flock?

 

[Isaac 0]

You can easily check for fertility by cracking the eggs open and looking for a ring around the white spot of the yolk , but they should fertile if you have seen him mating them. If you want her to hatch , Yes you can leave her eggs in the nest or put them in a dog kennel so she is protected from the other ducks but ducks can sometimes be picky about where they want to nest.

I have never had good luck relocating broody ducks,I prefer to block off the area with fencing,plywood ect. she picked so there ducks cant harass her and so the babies cannot escape.If you do choose to relocate her nest many people recommend doing it a at night.