Does anyone know if drakes in eclipse plumage are still fertile? I just got some ducks that I've been waiting for for a long time, and was hoping to still hatch some eggs from them this year. They're all in their eclipse plumage, and I know it's late in the season. I generally stop setting eggs by the end of May, or early June at the latest. Another question: How long after separating the ducks from the flock should I wait before I can be sure that the eggs are "pure"? I know that for chickens it can be up to 2 weeks, but I haven't found much information on ducks.