Greater scaup
The greater scaup is a distinguished diving duck native to large coastal bays in the northern hemisphere during the warmer months of spring and summer. Notable for their exquisite plumage, male greater scaups feature a striking glossy green and black head, bright yellow eyes, and a predominantly white body with black markings, while females display a more subdued brown coloration. These ducks typically range from 15 to 20 inches in length and have a wingspan of 28 to 33 inches. Greater scaups are social birds, often seen in large flocks or "rafts," and are adept divers, capable of foraging for food underwater for up to 30 seconds. Their diet primarily consists of mollusks like mussels and cockles, as well as other aquatic organisms when in freshwater.
During winter, they migrate south to find warmer waters, returning to their breeding territories in the spring. Courtship involves vocalizations from both males and females, after which the female constructs a nest and lays six to nine eggs. The incubation period lasts about 24 to 28 days, and the ducklings are independent swimmers shortly after hatching. Greater scaups have a lifespan of up to 20 years but face predation from various animals and human activities. As a species, they are currently not considered threatened.
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Greater scaup
The greater scaup is a duck that makes its home on large coastal bays in the far northern hemisphere during the spring and summer. Large flocks of these excellent divers gather to find food, such as mussels. The name scaup may come from the word scalp, an old word for a bed of mussels.
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Anseriformes
Family: Anatidae
Genus: Aythya
Species: Marila
Bright yellow eyes gaze from the bold, glossy green and black head of the male greater scaup. The neck, breast, and shoulders of this duck are also pure black, as are his rump and tail feathers. The middle of his body is white all the way around, except that on his back he has fine, black, mottled markings mixed in with the white. The female has brown plumage with a white patch around the base of her bill.
Greater scaups are around 15 to 20 inches (38 to 51 centimeters) long and weigh up to three pounds (1 1/3 kilograms). Their wingspan is between 28 and 33 inches (71 to 84 centimeters).
Large flocks of scaups live at sea much of the time, floating and feeding comfortably in groups called rafts even in stormy weather. They rarely come ashore other than to breed. Winter months force the scaups to migrate south to inland waters in and to coastlines in North America which are warmer than the Arctic. The birds tend to live on bodies of water which are not more than 20 feet (six meters) deep. They are diving ducks which can dive and swim underwater for 30 seconds at a time. Their plumage and body fat keep them warm even in the cold Arctic seas. Along with worms, insects, and small crustaceans, they mainly eat mollusks, especially mussels and cockles. The name scaup may come from an old word "scalp," which refers to a mussel bed. When they are in freshwater, the ducks hunt for insect larvae and worms, as well as foraging for aquatic plants and various seeds.
Before they migrate north again from their winter grounds, male and female scaups form pairs. During this courtship, the male coos, and the female makes harsh "karr" sounds. Migration occurs in the spring, shortly before the mating season begins in May. Each pair claims its own territory or joins a colony of other scaups and seabirds. The female lays between six and nine eggs in the nest which she builds on the ground among the vegetation. The male leaves her as soon as she lays her eggs and begins their incubation. Incubation lasts 24 to 28 days. Only a few hours after hatching, the ducklings can swim and dive, and they stay with their mother until they are able to fly at five or six weeks of age. One to two years later they are able to breed.
The predators of the greater scaup include owls, skunks, raccoons, foxes, coyotes, and humans. Greater scaups can live up to 20 years, although most live far less. They are not a threatened species.
Bibliography
Buckingham, Stephen. “Greater Scaup Overview.” All About Birds, 2024, www.allaboutbirds.org/guide/Greater‗Scaup/overview. Accessed 5 Apr. 2024.
Polan, Jason. “Greater Scaup - Audubon Field Guide.” National Audubon Society, 2024, www.audubon.org/field-guide/bird/greater-scaup. Accessed 5 Apr. 2024.