Some call them hens but actually it's drake= male duck and duck for female.
I have seen people call female ducks "duck" rather than "hen" but I was not sure why someone would use "drake" for a male duck and then use a gender neutral term for a female duck. I thought they were reluctant to use the term "hen" because they think of hens as chickens and don't realize it is a term for a female. Are you saying it is more correct to call a hen duck a duck and a drake duck a drake? To me that is like calling a hen chicken a chicken rather than a hen.