Species: Aythya affinis
Lesser Scaup
Species
Show on Lists
Encyclopedia of Puget Sound
Classification
Kingdom
Animalia
Phylum
Craniata
Class
Aves
Order
Anseriformes
Family
Anatidae
Genus
Aythya
NatureServe
Classification
Other Global Common Names
Pato Boludo-Menor - petit fuligule
Informal Taxonomy
<p>Animals, Vertebrates - Birds - Waterfowl</p>
Formal Taxonomy
Animalia - Craniata - Aves - Anseriformes - Anatidae - Aythya
Ecology and Life History
Migration
<p>false - false - true - Migrates northward usually in March-April, arriving in far north late May-early June. Departs far north by the end of September, migrates southward through U.S. mainly October-November. Scaup that breed along Beaufort Sea coast winter throughout broad range of central and southern latitudes in North America, from coast to coast.</p>
Non-migrant
false
Locally Migrant
false
Food Comments
Feeds on seeds of pondweeds, widgeon grass, wild rice, sedges, bulrushes; also crustaceans, mollusks, and aquatic insects. Diet varies with location. Most feeding occurs in fresh water of various depths, often 3-8 m. In midwinter in Louisiana and in spring and fall in northwestern Minnesota, important foods were crustaceans, insects, and mollusks; in fall, immatures fed heavily on amphipods and did not consume fishes or fingernail clams, which were important in adult diets; by dry weight, animal foods comprised over 90% of the diet in fall and spring, 61% in midwinter (Afton et al. 1991). During fall migration in Ontario, fed in large numbers on zebra mussels (DREISSENA) (Wormington and Leach 1992).
Reproduction Comments
Egg-laying begins in early May in the south to mid-June in the north. Clutch size: 6-15 (usually 9-12, largest in older females). Incubation: 22-27 days, by female (Terres 1980). Young are tended by female. Variable percentage of yearling females do not breed.
Ecology Comments
NON-BREEDING: usually in flocks on open water (Ridgely and Gwynne 1989).
Length
42
Weight
850
Conservation Status
NatureServe Global Status Rank
G5
Global Status Last Reviewed
1996-11-21
Global Status Last Changed
1996-11-21
Other Status
<p>LC - Least concern</p>
Distribution
Conservation Status Map
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Global Range
H - >2,500,000 square km (greater than 1,000,000 square miles) - H - BREEDING: central Alaska and Mackenzie Delta to northern Manitoba and northern Ontario south to southern British Columbia, northern Idaho, northern Wyoming, northern North Dakota, and Minnesota, casually or irregularly east to central Quebec and south to Washington, central California, northern Utah, central Colorado, central Nebraska, northwestern Iowa, central Illinois, and northern Ohio (AOU 1998). NON-BREEDING: southern Alaska, and from southern British Columbia, southern Idaho, Utah, northeastern Colorado, Kansas, Iowa, southern Great Lakes region, and New England south throughout the southern U.S., Middle America, and West Indies to northern Colombia, northern Venezuela (very small number at southern limit of this range); small numbers in Hawaii. Primary wintering areas in the U.S. include the Atlantic and Gulf coastal plains, Mississippi Valley north to the Ohio River, and the Pacific states, plus southern British Columbia; the highest densities occur in southern Florida and along the Mississippi River (Root 1988).
Global Range Code
H
Global Range Description
>2,500,000 square km (greater than 1,000,000 square miles)