Greater scaup refers to a seabird mentioned by Aristotle and others and is thought to refer to a duck, auklet or other seabird. The species name "marila" is from the Greek word for charcoal embers or coal dust. The greater scaup was first studied by Linnaeus in 1761. Male greater scaup from America are distinguishable from those in Europe and Asia by the stronger vermiculations, worm-like carvings or marks on the mantle and scapulars, and are considered a separate subspecies, "A. m. nearctica". Females of the two subspecies are indistinguishable. Based on size differences, a Pleistocene paleosubspecies, "Aythya marila asphaltica", has also
New Zealand scaup for twenty to thirty seconds and go down three metres to look for aquatic plants, small fish, water snails, mussels and insects. It is sometimes seen with the Australian coot ("Fulica atra"); it is thought that the scaup takes advantage of the food stirred up by the coots as they fossick for shrimps. It is found throughout both the North and South Islands of New Zealand in deep freshwater lakes and ponds. Unlike other members of this genus, the scaup is not migratory, although it does move to open water from high country lakes if they become frozen in winter.