I call this method of dabbling, bottoms up. The other dabbling method involves skimming food right below the surface. These are mallards, dabbling ducks. With a female bufflehead in the background.
Mallards (Anas platyrhynchos)
male mallardfemale mallardmallardanas platyrhynchoswhite rock lakedallas texassunset bayaquatic birdaquaticwater fowldabbling duckduckfeedingeatingdabblerdabblingbuttsduck butts
From Aquatic Birds