Aythya affinis
The Lesser Scaup is the Oreo cookie of the Rocky Mountain duck clan: black at both ends and white in the middle. It is one of the most abundant divers throughout our region, and it can be seen in large rafts during migration. Several female scaups may care for two or more broods of young. Although the ducklings are tended by the females, they feed themselves. Lesser Scaups, also known as Bluebills, leap up neatly before diving underwater, where they propel themselves with powerful strokes of their feet. The scientific name affinis is Latin for 'adjacent and allied'-a reference to this scaup's close association to other diving ducks. 'Scaup' may be a reference to this bird's preferred winter food-shellfish bed are called 'scalps' in Scotland-or it may be a phonetic imitation of one of its calls. |
I.D.: Male: dark head with hints of purple; black breast and hindquarters; yellow eyes; dirty white sides; grayish back; blue-gray bill. Female: dark brown; well-defined white patch at the base of the bill. Size: L 15-18 in. (38-46 cm). Range: locally common breeder and uncommon to common migrant throughout the Rockies. Habitat: woodland ponds and lake edges with grassy margins. Nesting: typically on the Great Plains; in tall, concealing vegetation, generally close to water; occasionally on islands; nest hollow is built of grass and lined with down; female incubates 8-10 eggs for about 25 days. Feeding: dives underwater to depths of about 6 ft. (1.8 m) for aquatic invertebrates, mostly amphipods and insect larvae, and vegetation. Voice: alarm call is a deep scaup. Male: courtship call is a soft whee-oooh. Similar Species: Ring-necked Duck: male has a white shoulder slash and a black back. |
