Scaup

Scaup is the common name for two species of diving ducks in the genus Aythya: the greater scaup (Aythya marila) and the lesser scaup (Aythya affinis). They are medium-sized waterfowl that dive for food and are found across northern regions of North America, Europe, and Asia during breeding and wintering seasons. The two species are similar in appearance, with males generally having a darker head with iridescent sheen, lighter underparts, and a gray back, while females are brownish with a lighter face. Both species show a distinctive white wing patch (speculum) and differ primarily in size and subtle plumage details.

Scaups breed in boreal wetlands and tundra, establishing nests near water concealed among vegetation. Typical clutches contain about 6–11 eggs, incubated by the female for roughly 21–23 days. Ducklings are precocial, leaving the nest soon after hatching and following their mother to water. Their diet consists mainly of aquatic invertebrates, seeds, and plant material, gathered by diving rather than surface feeding. Foraging locations include ponds, lakes, rivers, and coastal bays.

Migration patterns vary by region; many populations move to coastal or inland wintering grounds with ice-free waters in late fall. Population trends are generally of least concern on a global scale, but regional declines have been reported due to habitat loss, pollution, and hunting pressure in some areas. Scaup are monitored by wildlife agencies and are a common focus of waterfowl conservation and hunting regulations in affected regions.