White-winged Scoter

Identification

The white-winged scoter is the largest of North America's three scoter species, a robust sea duck characterized by its bulky shape and distinctive large bill. Males average 55 cm in length and weigh around 1,380 g, while females are slightly smaller at 52.3 cm and 1,180 g on average. The species takes its name from the conspicuous white secondary flight feathers visible in flight, though these markings may be hidden when the bird is swimming.

Adult males are unmistakable: entirely black plumage with striking white patches around the eye and a white wing speculum, plus an orange-red bill with a prominent black knob at the base. Females and immatures are far trickier, appearing brownish overall with highly variable facial patterns. Younger birds display white spots in front of and behind the eye, while older females may lack these patches entirely, appearing uniformly chocolate-brown. A key distinguishing feature across all ages is the feathered gape—the corner of the bill where it meets the face—which sets this species apart from similar-looking scoters like the surf scoter. Adult plumage takes three years to fully develop in males.

Range & Habitat

White-winged scoters breed across the largest range of any North American scoter, primarily in boreal forest from Alaska through western Canada, with populations thinning eastward toward Hudson Bay and southward into the Canadian Prairies. They winter further south, gathering in large, tightly packed flocks on the Great Lakes, the coasts of the northern United States, and southern Canadian coastal waters. The species occasionally appears as a vagrant in Europe, including records from Scotland, Iceland, Norway, and Ireland.

Behaviour & Diet

White-winged scoters are monogamous ducks that form pairs in late summer, suggesting enduring pair bonds. Nests are built on the ground near water in woodland or tundra, with females laying five to eleven pinkish eggs that incubate for 25 to 30 days. After hatching, broods often amalgamate due to aggressive interactions between nesting females, sometimes creating creches of up to 100 ducklings. Young ducks gain flight capacity between 63 and 77 days of age.

These are benthic feeders that dive between 5 and 20 meters in winter and 1 to 3 meters on breeding grounds. Their large size allows them to pursue larger prey and dive deeper than smaller scoter species. In freshwater, they primarily consume crustaceans and insects, while in saltwater they favor molluscs and crustaceans—particularly amphipods like Hyalella azteca in freshwater, and rock clams, Atlantic razor clams, and Arctic wedge clams in marine environments. Their gizzards, which comprise 8 percent of body mass, are powerful enough to crush hard-shelled molluscs.

Best Time & Places to See It

Winter is the prime season for viewing white-winged scoters in accessible locations. Look for them on the Great Lakes and Atlantic and Pacific coasts of the northern United States and southern Canada, where they gather in distinctive tight flocks on suitable coastal waters. During breeding season, birders visiting Alaska and western Canadian boreal forests in summer may encounter them on large lakes and marshes, though they are less common in eastern regions.

Photography Tips

Photographing white-winged scoters presents both challenges and rewards. Males in breeding plumage are highly photogenic with their striking black-and-white contrast and colorful bills, but patience is essential as these ducks often cluster tightly together on the water. Capture them in flight to showcase the namesake white secondary feathers, which are among the species' most distinctive features. Females and immatures require closer inspection; photograph them from multiple angles to document the subtle facial patterns and head shape that distinguish them from closely related species. Winter coastal locations offer the best opportunities, where large flocks may be relatively stationary.