Greater scaup days. The down-covered ducklings are able to follow their mother in her search for food immediately after hatching. Greater scaup eat aquatic molluscs, plants, and insects, which they obtain by diving underwater. They form large groups, called "rafts", that can number in the thousands. Their main threat is human development, although they are preyed upon by owls, skunks, raccoons, foxes, coyotes, and humans. Greater scaup populations have been declining since the 1980s; however, they are still listed as a species of least concern on the IUCN Red List. The genus name "Aythya" is derived from the Ancient Greek "aithuia" which
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.