Greater Scaup

About the Greater Scaup

The Greater Scaup is the salt-water scaup - a chunky diving duck of big open water, the drake black at both ends and pale in the middle with a smoothly rounded, green-glossed head, the hen warm brown with a bold white face patch at the bill base. It breeds on tundra lakes around the entire top of the world, one of the few circumpolar ducks.

Scaup dive for their food, riding low rafts on open water and disappearing in smooth rolls to take clams, mussels, snails, and aquatic plants from the bottom - on the coast, whole rafts work shellfish beds together, hundreds of birds diving and surfacing in loose rotation.

Telling Greater from Lesser Scaup is a classic waterfowl test, and Texas birds punish overconfidence: Greater shows the rounder head with its highest point forward, a broader bill with a bigger black nail, and in flight a white wing-stripe that runs well out into the primaries, where Lesser's goes gray. Lighting changes the head gloss - green versus purple - often enough that shape matters more than sheen.

In Texas the Greater Scaup is the scarcer of the pair, wintering mainly on the coastal bays with a few among the big Lesser Scaup rafts on inland reservoirs. Working through a thousand-bird scaup raft looking for the broad-billed, round-headed exceptions is a proper Texas winter exercise.