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
FULAGULA (Pochard, Tufted Duck, Scaup).
"British Birds in their Haunts" by Rev. C. A. Johns
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.