I have been raising ducks for 12+ yrs. I had kept females only for many years. After getting a couple of males, I had tried twice to allow some of the broody girls (once a crested and once a khaki) to hatch some eggs. One both occasions, multiple eggs hatched but several ducklings were trampled (literally flattened in the nest). The only ducklings that survived were males and they seemed to interact normally with the sitting "mother" duck (i.e. she cared for them and raised them well.) Has anyone else seen this? Do you think its a coincidence that only males survived? Other thoughts?? I have avoided further hatchings because I really don't want more male-only hatchings.