(Courtesy of Jan Harteman
These large diving ducks reach lengths of 26" (65 cm). The males have a solid black head with a greenish sheen, a white collar and a distinctive red-brown chest patch. The females have a gray back and a rust colored head.
They feed almost exclusively on fish and have a specially adapted, spikelike, serrated-edge bill used to catch and devour fish. They are found in the Bay during winter.