ducks breeding...

[Just Hatch duck]

Hi, i have a drake and two ducks i recently separated them from my chooks because i found out they won't breed with chickens around... but its been a month or two and they started nesting but i think they aren't fertile because i candled them and can't find any veins or blood vessels but they acted as though they nested and became protective, but after 3 weeks of constantly laying they've turned black also. I've never seen them mate and i feel as though they haven't but not sure what to do?
cheers bree

 

[chickens really]

What kind of Ducks?...The eggs need to be incubated by the Hen in order to start developing...Meaning she will need to set them for at least a week till you will see any signs of veins or development..Not all Hens go Broody..It could be the time of year...Hormones go higher in spring and breeding season begins...