The lake duck is a small, South American stiff-tailed duck. It is also called the Argentine blue-bill, Argentine blue-billed duck, Argentine lake duck, or Argentine ruddy duck.
Region
Southern South America
Typical Environment
Found primarily in Argentina and central Chile with movements into adjacent Uruguay, Paraguay, and southern Brazil outside breeding. It favors shallow freshwater lakes, marshes, and slow backwaters with abundant emergent reeds and submerged plants. The species is strongly aquatic and rarely ventures far from cover. It uses dense vegetation for nesting and refuge and open pockets for diving and foraging.
Altitude Range
Sea level to 1500 m
Climate Zone
Temperate
Ease of Keeping
Beginner friendly: 2/5
The lake duck is a compact, diving stiff-tailed duck of southern South America, famed for the male’s bright sky-blue bill in breeding season and cocked, spiky tail. It spends most of its time on the water, diving rather than flying to escape danger. Notably, males possess one of the longest penises relative to body size in birds, a rare anatomical trait. It prefers calm, reedy lakes and ponds where it can feed and nest among dense vegetation.
Females
Female ducks have a corkscrew vagina.
Temperament
secretive and wary
Flight Pattern
short rapid wingbeats; reluctant flier, primarily a diver
Social Behavior
Outside breeding, it may gather loosely on suitable lakes but generally keeps to cover. Nests are built low over water among reeds, with the female incubating. Courtship includes tail-raising and bill displays by the male. Broods are reared in sheltered marshes where ducklings dive readily when alarmed.
Migratory Pattern
Partial migrant
Song Description
Usually quiet; males give soft grunts and rattling or clicking notes during courtship. Females utter low quacks and hissing calls when disturbed. Vocalizations are most frequent at close range within dense vegetation.
