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Lesser Scaup

Aythya affinis

pair of Lesser Scaups


This medium-sized diving duck is 15 to 18 inches long, has a wingspan of 27 to 31 inches, and weighs between 1 and 2 pounds.

The bill is bluish with a small black tip, the eyes are yellow, and the legs are grayish with dark gray webs. During the breeding season the male has a black head, chest, and rear end, and gray sides. The female is drabber and more brown, with a white patch at the base of the bill.

Distribution and Habitat

The breeding range of the lesser scaup extends from central Alaska to Hudson Bay southward to Minnesota, northern Colorado, and extreme northern California. Its winter range extends across the southern United States, southward through Mexico into northern South America, and throughout the Caribbean.

distribution of the Lesser Scaup

The lesser scaup prefers open stretches of fresh water in the summer, but can be found on either fresh or brackish water in the winter.


The nest is a bowl of grasses or other vegetation, lined with down, placed either directly on the ground or in a mound of vegetation over water. A typical clutch contains 8 to 10 pale to dark olive or greenish buff eggs.

Chicks are capable of diving under water soon after hatching, but are too buoyant to stay under for more than a moment or two. By the time they are 5 to 7 weeks old, however, they are able to dive for up to 25 seconds and swim underwater for up to 60 feet.


The diet of the lesser scaup includes aquatic plants and insects, seeds, snails, clams, and crustaceans.

Scientific Classification

phylum Chordata
subphylum Vertebrata
class Aves
order Anseriformes
family Anatidae
subfamily Anatinae
genus & species Aythya affinis

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The Robinson Library >> Science >> Zoology >> Birds >> Order Anseriformes

This page was last updated on September 25, 2017.