• WordNet 3.6
    • n scaup diving ducks of North America having a bluish-grey bill
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Webster's Revised Unabridged Dictionary
    • Scaup A bed or stratum of shellfish; scalp.
    • Scaup (Zoöl) A scaup duck. See below.
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Century Dictionary and Cyclopedia
    • n scaup A Scotch form of scalp.
    • n scaup A duck, Fuligula or Fulix marila and related species. The common scaup inhabits Europe, Asia, and North America. It is from 18 to 20 inches long, and from 30 to 35 in extent of wings; in the male the head, neck, breast, rump, and vent are black; the back and belly are white, the former finely vermiculated with zigzag lines of black; the wing has a white speculum, and is lined with white; the bill is dull-blue, with black nail; the feet are dark-plumbeous; the iris is yellow. In the female a belt of white encircles the bill. A smaller species is F. affinis of North America. The ring-neck scaup, F. collaris or rufitorques, has a chestnut or orange-brown ring around the neck. All the scaups are near the pochards and redheads (including the canvasback) in general pattern of coloration, but the males have black instead of reddish heads. The American scaups, of 3 species, have many names, mostly local, as broadbill and bluebill (both with various qualifying words prefixed), blackhead and blackneck (with qualifying words), raft-duck, mussel-duck, greenhead, grayback, flock-duck, flocking-fowl, troop-fowl, shuffler, etc.
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Chambers's Twentieth Century Dictionary
    • n Scaup skawp a sea-duck of genus Aythya, of northern regions, related to the pochard.
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Webster's Revised Unabridged Dictionary
See Scalp a bed of oysters or mussels
Chambers's Twentieth Century Dictionary
Ice. skálp—in skálp-hæna.


In literature:

Greater scaup prefer large open water areas; lesser scaup often use marshes and ponds.
"Ducks at a Distance" by Robert W. Hines
At Lake Worth I saw a gentleman feed Scaup Ducks that swam to within two yards of his boat.
"The Bird Study Book" by Thomas Gilbert Pearson
The lesser scaup, or little blue-bill (=Aythya affinis=) has a white speculum also, but the sheen of the head and neck is purple.
"Game Birds and Game Fishes of the Pacific Coast" by Harry Thom Payne
FULAGULA (Pochard, Tufted Duck, Scaup).
"British Birds in their Haunts" by Rev. C. A. Johns

In news:

The daily bag limit on ducks is six and may include no more than four mallards (no more than two of which may be females), two pintails, one canvasback, one mottled duck, one black duck, three wood ducks, two scaup and two redheads.
But unlike canvasbacks, scaup didn't dive all the way to the bottom.
Wilson, naturespicsonline Lesser scaup ducks, common migrants and winter residents on Tennessee's ponds, lakes and rivers, often arrive in large flocks.
Although male ring -necked ducks superficially resemble their counterparts in greater and lesser scaup, their peaked, angular head profile, distinctive white bill markings and uniformly dark upper wings distinguish them.
In addition to Pied-Billed Grebe, there are Scaups, Coots, Widgeons Buffleheads and even a Cormorant on the lake.