Unlike dabbling green-winged teals, lesser scaup are diving ducks that largely feed while swimming underwater rather than dabbling at the surface. These ducks also make more use of seasonal wetlands than do other species of diving ducks.

Lesser scaup, with their distinctive bright white wing stripe and gray bills, are quite wide-ranging and during the winter, migrants appear across many areas of the continental U.S.. During migration, they are known to form large groups (called “rafts”) that can be up to a mile wide on large inland lakes.

Lesser scaup primarily breed in the boreal forests of Canada and Alaska. During migration they travel through the Mississippi Valley to the Gulf of Mexico or east through the Great Lakes region to the Atlantic coast. Unfortunately, lesser scaup populations have declined markedly since the 1980s. Because so many of these birds rely on the boreal forest for breeding ground, changes to the lakes and wetlands within the forest could have disastrous effects on this duck’s continued survival.

Greater Scaup or Lesser Scaup?

As the names suggest, lesser scaup are smaller than greater scaup. Because it can be difficult to accurately differentiate between the two birds when they’re in flight, most scaup are counted together. However, lesser scaup are far more numerous are believed to make up close to 90 percent of the entire scaup population. One way to tell the difference between the two ducks, besides their size, is that the lesser scaup has a black head with a purplish tint and the greater scaup has a black head with a more greenish cast.

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Nature picture credits (left to right): Lesser scaup ©Tim Fitzharris / Minden Pictures; Lesser scaup in pond © James Metcalf.