American Black Duck vs Steller's Eider
Anas rubripes comparado con Polysticta stelleri
Side-by-Side Comparison
| Atributo | American Black Duck | Steller's Eider |
|---|---|---|
| Nombre científico | Anas rubripes | Polysticta stelleri |
| Orden | Anseriformes | Anseriformes |
| Familia | Anatidae | Anatidae |
| Estado de conservación | Least Concern | Vulnerable |
| Longitud | — | — |
| Envergadura | 53,4 cm (21.0 in) | 40,7 cm (16.0 in) |
| Peso | 1211,25 g (42.73 oz) | 815,75 g (28.77 oz) |
| Dieta | Eats fish and aquatic invertebrates; dives in coastal and freshwater habitats; diet shifts toward molluscs … | Eats molluscs, crustaceans, and aquatic invertebrates; dives in shallow coastal and estuarine habitats; diet invertebrate-dominated. |
| Tamaño de la puesta | 1-17 | 3-10 |
| Population Trend | — | — |
Habitat Comparison
Hábitats compartidos
American Black Duck only
Steller's Eider only
Ninguno
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.
Steller's Eider
Breeds on low-lying coastal tundra in Arctic Russia and occasionally Alaska. Winters on shallow rocky sea coasts, kelp beds, and sheltered bays in the Baltic Sea and Pacific coast of Alaska. Listed as Vulnerable.
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.
Steller's Eider
Male produces a low, soft cooing note; female gives a guttural, grunting purr. Quieter than other eiders; the male's gentle cooing is unlike the louder calls of the Common Eider.
Geographic Range & Migration
American Black Duck
Breeds in the steppe zone of Central Asia; winters in South Asia, East Africa, and coastal Southeast Asia.
Steller's Eider
Breeds in boreal Canada and Alaska; winters along Pacific and Atlantic coasts and on large interior lakes of the US.
Estado de conservación
American Black Duck
Steller's Eider
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 …
Steller's Eider
Males have white head with green nape spot, black eye patch and chin; orange-buff underparts; black back with white wing patches. Females mottled dark brown with blue speculum bordered white. …
About These Birds
American Black Duck
El pato negro americano es un gran pato de color marrón muy oscuro con una cabeza más clara y un llamativo espéculo alar púrpura. Habita en humedales del este de Norteamérica y se está hibridando cada vez más con el pato de collar introducido en su rango, lo que representa una amenaza para su pureza genética. Prefiere marismas costeras, pantanos boscosos y lagos tranquilos.
Steller's Eider
El eider de Steller es el más pequeño de los eiders, con el macho de color blanco y negro con el pecho y los flancos de color canela-naranja. Cría en la tundra costera del norte de Siberia y Alaska, y pasa el invierno en costas marinas del norte del Pacífico y el norte del Atlántico. Está clasificado como vulnerable, con declives de población en Alaska.