American Black Duck vs Blue-billed Duck
Anas rubripes compared with Oxyura australis
Side-by-Side Comparison
| Attribute | American Black Duck | Blue-billed Duck |
|---|---|---|
| Scientific Name | Anas rubripes | Oxyura australis |
| Order | Anseriformes | Anseriformes |
| Family | Anatidae | Anatidae |
| Conservation Status | Least Concern | Least Concern |
| Length | — | — |
| Wingspan | 53.4 cm (21.0 in) | 30.8 cm (12.1 in) |
| Weight | 1211.25 g (42.73 oz) | 837.75 g (29.55 oz) |
| Diet | Eats fish and aquatic invertebrates; dives in coastal and freshwater habitats; diet shifts toward molluscs … | Dives for aquatic invertebrates, seeds, and plant material in Australian freshwater lakes and swamps. Highly … |
| Clutch Size | 1-17 | 5-6 |
| Population Trend | — | — |
Habitat Comparison
American Black Duck
Freshwater and brackish wetlands in eastern North America from Atlantic Canada south along the coast to Georgia. Breeds in northern bogs and wetlands. Winters on coastal marshes, estuaries, and freshwater lakes.
Song & Call Comparison
American Black Duck
Female produces a loud, deep quacking series; male gives a low, raspy grunt. Voice is deeper and huskier than a Mallard; pairs call powerfully across northeastern North American wetlands.
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
American Black Duck
Breeds in the steppe zone of Central Asia; winters in South Asia, East Africa, and coastal Southeast Asia.
Blue-billed Duck
Resident in southwestern and southeastern Australia. Found on freshwater swamps and lakes, avoiding arid and tropical regions.
Conservation Status
American Black Duck
Blue-billed Duck
How to Tell Them Apart
American Black Duck
Sooty dark brown body; head and neck paler buff with dark streaking. Iridescent purple speculum without white border. Males have yellow-green bill; females olive with orange blotches. Silvery underwings in …
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
American Black Duck
A large dark brown dabbling duck closely resembling a very dark female Mallard, with purple speculum, yellowish-olive bill in males, and orange legs. Common in eastern North America. Hybridizes freely with Mallard; pure populations declining in the interior.
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.