Thanks Nate, Bob and John.
I think they are normally more skittish than Mallards. This is from a lake in a city park so the ducks are very accustomed to people and if you sit down next to the water and move slowly they swim very very close at times. I have some shots sort of like the one you are describing John and I like your thinking on the pose as well as dof.
This is an immature Wood Duck shot at f/4