Question; do you use Iris Enhance for your bird shots? I ask because the eye looks a bit dark but it's possible these ducks have such eyes. I have a preset in my LR brushes with the settings. Basically it is used to brush the eye and make it pop slightly. It's common practice in bird photography and it makes a serious difference.
I used it here:
You don't really consciously notice it in a shot itself but since we humans are attracted to eyes, it gives a whole different impression. Maybe you used it and the duck's eyes are even darker. If, ignore me.