by Frank Keim
In the spring this diving duck looks a little like its cousin, the Surf scoter. One of its Yup’ik names Akacakayak, is even the same. As with its cousin, it too looks like it had a head-on collision and stubbed its nose. It’s other name, Cetuskaq, used mostly in the Nunivak Island area, refers to the way the duck follows the current along the Bering Sea shore or down a river as it searches for food.
This scoter is the largest of the three species found in the LYK Delta, and before they land, feeding flocks usually fly low over the sea in long, wavering lines, although in migration they may fly much higher, sometimes suddenly dropping hundreds of feet with a loud swooshing noise. In the Delta it is only found as a migrant in the Bering Sea, or a nester (in the interior of the Delta where it nests in open country around tundra lakes and ponds and slow-moving rivers.
While foraging for shellfish or other food, they dive and swim underwater, propelled mainly by their feet, with wings only partly open to help in maneuvering and sudden thrusts. Small items of food are swallowed underwater, but large shellfish are brought to the surface and swallowed whole there.
Before reaching their LYK nesting grounds in late May, White-winged scoters perform some interesting courtship displays. In one, several males may surround a lone female, with each of the males lowering his head, arching its back, then rushing forward and chasing her for short distances either on top of the water or under the surface. Multiple males may pursue the female in the same way.
Nesting begins late, with clutches often not complete until late June or early July. The female selects and builds her nest on the ground, usually close to water in a patch of dense brush. The habitat in the LYK Delta is perfect for their needs, and is the reason why so many of them nest there. Where nest building takes place on islands, several nests may be close together. The female alone selects the site, then clears a shallow depression, adding plant material and lining it with her own down.
Usually 9-10 pale buff or pinkish eggs are laid, and incubation is for 25-30 days by the female alone. She covers her eggs with down when leaving her nest. The young are precocial, that is, they are already covered with down feathers after hatching and able to feed themselves almost immediately. For this reason, they leave the nest with their mother shortly after hatching. Their mother tends and broods them while small, but they already know how to feed themselves. Their age at first flight is between 8-11 weeks.
Like their parents, young birds feed mostly on freshwater crustaceans and aquatic insects and their larvae, plus a few small fish. Later, they will feed on small mollusks and plants such as, pondweeds, sea lettuce and others.
They generally migrate in small flocks, although large numbers may gather at stopover points. On overland passage to coastal wintering areas, they often fly very high. Adult males tend to winter somewhat farther north than females or younger birds.
White-winged scoters are still widespread and numerous, although wintering concentrations are extremely vulnerable to oil spills and other types of pollution on the open sea.
As with the other scoter species, they also have some interesting nicknames, among them: Assemblyman; American velvet scoter; velvet duck; bell-tongue coot; black white-wing; brant coot; bull coot; black surf duck; pied-wing coot; sea brant; Uncle Sam coot; and white-wing surf duck. Velvet scoter is a European subspecies of the duck which is similar to the North American species, but the male lacks a knob at the base of the bill.
Their scientific name is Melanitta fusca. The genus name is derived from ancient Greek, melas “black” and netta “duck”. The species name is from the Latin, fuscus “dusky brown”.
•Although the White-winged Scoter winters primarily along the coasts, small numbers winter on the eastern Great Lakes. Populations on the Great Lakes may have declined during the 1970s, but appear to be increasing in response to the invasion of the zebra mussel, a new and abundant food source.
•The White-winged Scoter often nests in association with gull breeding colonies. Although the gulls would happily eat the eggs and chicks of the scoter, the dense vegetation where the scoter nests keeps them safe.
•The White-winged Scoters found in North America and eastern Asia differ from those found in Europe in the structure of the bill and trachea of the male. The European “Velvet Scoter” male has only a slight swelling on the top of the bill, and the bill is yellow, not orange. The two forms sometimes are regarded as distinct species.
•The oldest recorded White-winged Scoter was a female, and at least 18 years, 1 month old when she was observed at a nest in Saskatchewan, Canada.