The blue-billed duck is a small Australian stiff-tailed duck, with both the male and female growing to a length of 40 cm (16 in). The male has a slate-blue bill which changes to bright-blue during the breeding season, hence the duck's common name. The male has deep chestnut plumage during breeding season, reverting to a dark grey. The female retains black plumage with brown tips all year round. The duck is endemic to Australia's temperate regions, inhabiting natural inland wetlands and also artificial wetlands, such as sewage ponds, in large numbers. It can be difficult to observe due to its cryptic nature during its breeding season through autumn and winter. The male duck exhibits a complex mating ritual. The blue-billed duck is omnivorous, with a preference for small aquatic invertebrates. BirdLife International has classified this species as Least concern. Major threats include drainage of deep permanent wetlands, or their degradation as a result of introduced fish, peripheral cattle grazing, salinization, and lowering of ground water.
Region
Southern Australia
Typical Environment
Found across temperate southern Australia from the southwest of Western Australia through South Australia to Victoria, New South Wales, and Tasmania. It favors deep, permanent freshwater or brackish wetlands with dense emergent vegetation, including lakes, swamps, and large lagoons. The species also uses artificial wetlands such as sewage ponds and farm dams, sometimes in large numbers. It is generally sedentary but will disperse locally in response to drought or changing water levels.
Altitude Range
Sea level to 1200 m
Climate Zone
Temperate
Ease of Keeping
Beginner friendly: 2/5
This stiff-tailed duck is notable for the male’s bright sky-blue bill during the breeding season and a spiky tail often held upright. It is a powerful diver, spending long periods underwater and preferring to swim or sink rather than take flight when disturbed. Breeding typically occurs in autumn–winter, and males perform elaborate bubbling and bill-fountain displays. The species relies on deep, permanent wetlands, including artificial habitats like sewage ponds.
Adult male at Lake Monger in Western Australia
Adult male in Perth Zoo
Temperament
secretive and wary
Flight Pattern
short rapid wingbeats; reluctant flier, strong diver
Social Behavior
Outside the breeding season, birds may gather in loose flocks or rafts on large, open waters. During autumn–winter, males perform complex courtship displays including bubbling and bill-fountain behaviors. Nests are built by females in dense reeds or rushes over water; females incubate and tend the young while males do not provide prolonged care.
Migratory Pattern
Resident
Song Description
Generally quiet; males give soft grunts, pops, and bubbling sounds during display. Females utter low quacks or growls when alarmed.
