Great light, details and the reflection puts it over the top for me. I' surprised the water at the bottom looks so different than at the top. I'm not sure I have seen this species before, thanks for sharing! Do you also have images of the male?
A very good looking duck, don't believe I have seen it before.
Good exposure, with good detail in the darker feathers. Nice head angle. Lovely water, very soft looking. Sharp overall, but could stand just a tad more about the eye, just seems a bit soft there compared with back.
From a composition standpoint, just a bit tight for my tastes, but very close. The proportions are good, just needs a bit more all the way around.
If possible, just a bit lower on the shooting angle, would have maintained the nice reflection, but reduced the fore shortening (sp?) a bit.