Greater scaup to other diving ducks. The greater scaup forms large flocks, some of which can contain thousands of birds. When flocks are on flowing water, they will face the current, and as the ducks float backwards, some fly to the front of the flock to maintain position. Common predators of the greater scaup are owls, skunks, raccoons, foxes, coyotes, and humans. Greater scaup often find themselves entangled in fishing nets, thus large numbers of them drown in nets each year. Greater scaup can catch avian influenza, so future outbreaks have the potential to threaten greater scaup populations. Although the greater scaup
Greater scaup zinc, manganese, copper, lead, cadmium, cobalt and nickel in their tissue samples with varying concentrations of metals in different types of tissues. Further analysis revealed that the kidneys had the highest levels of cadmium, the liver had the highest levels of copper and manganese, the liver and the stomach had the highest levels of zinc, and the lungs and liver had the highest levels of iron. There was no difference in concentration when comparing genders. Greater scaup are rated as a species of least concern by the IUCN Redlist. During aerial population surveys greater and lesser scaup are counted together,