Black-headed Duck vs Blue-billed Duck
Heteronetta atricapilla compared with Oxyura australis
Side-by-Side Comparison
| Attribute | Black-headed Duck | Blue-billed Duck |
|---|---|---|
| Scientific Name | Heteronetta atricapilla | Oxyura australis |
| Order | Anseriformes | Anseriformes |
| Family | Anatidae | Anatidae |
| Conservation Status | Least Concern | Least Concern |
| Length | — | — |
| Wingspan | 34.7 cm (13.7 in) | 30.8 cm (12.1 in) |
| Weight | 528.5 g (18.64 oz) | 837.75 g (29.55 oz) |
| Diet | Parasitic; adults may feed on aquatic plants, seeds, and invertebrates in South American marshes. Diet … | Dives for aquatic invertebrates, seeds, and plant material in Australian freshwater lakes and swamps. Highly … |
| Clutch Size | 2 | 5-6 |
| Population Trend | — | — |
Habitat Comparison
Song & Call Comparison
Black-headed Duck
Male gives a soft, raspy peeping note; female produces a muted quack. An obligate brood parasite with reduced vocalizations; subdued calls suit its secretive lifestyle among Argentine reeds.
Blue-billed Duck
Male produces a mechanical, splashing display call with loud bill-drumming; female gives a harsh quack. The male's bizarre bubbling-cum-drumming display is spectacular on Australian lakes.
Geographic Range & Migration
Black-headed Duck
Resident in southern South America from southern Brazil and Bolivia south to Argentina and Chile. Found on lakes and marshes in open lowlands.
Blue-billed Duck
Resident in southwestern and southeastern Australia. Found on freshwater swamps and lakes, avoiding arid and tropical regions.
Conservation Status
Black-headed Duck
Blue-billed Duck
How to Tell Them Apart
Black-headed Duck
Male has distinctive jet-black head and neck, warm chestnut-brown back, and pale buff underparts; blue-grey bill with red base. Female is streaked brown above with pale supercilium and whitish underparts.
Blue-billed Duck
Breeding male is deep rich chestnut with black head and broad bright blue bill; tail often held erect. Female is dark brown with finely barred buff pattern on body and …
About These Birds
Black-headed Duck
A small diving duck (~530 g) of South America, family Anatidae, and the sole member of genus Heteronetta. Inhabits freshwater marshes and lakes in Argentina, Bolivia, Brazil, Chile, and Uruguay. Unique among waterfowl as an obligate brood parasite, laying eggs in nests of coots and other waterbirds. Feeds on seeds and aquatic invertebrates. Least Concern.
Blue-billed Duck
Australia's only endemic stiff-tailed duck (~840 g), family Anatidae, males recognized by deep chestnut plumage and a vibrant blue bill in breeding season. Inhabits deep freshwater lakes and swamps in southeastern and southwestern Australia. Dives for aquatic invertebrates and plant matter. Least Concern; dependent on permanent water bodies, vulnerable to drought cycles.