An eye-catching waterbird found on lakes and ponds with extensive floating vegetation. Long-tailed breeding adults are striking: the large white wing patch and head contrast sharply with its black body and bright yellow neck patch. Short-tailed wintering adults and juveniles have a brown back, white underparts, and a toned-down version of the breeder's head pattern. Vocalizations include a variety of nasal clucking and purring calls; song, seldom heard, a repeated, ringing “ku-woo.”