I have a mallard hen that built a nest outside the coop & has somehow convinced the other 3 hens to lay in her nest & she is broody. By the time I realized what was going on she had 18 eggs under her. The first few days she would only stay on the nest a few hrs. a day but today she hasn't come off the nest. I have no drakes!! What should I do? Remove all eggs in the nest then continue on a daily bases removing any fresh laid eggs? Will she just go somewhere else & build a new nest? I am new to ducks so any advice is welcomed!!