Snow Goose vs Black-headed Duck
Anser caerulescens comparado con Heteronetta atricapilla
Side-by-Side Comparison
| Atributo | Snow Goose | Black-headed Duck |
|---|---|---|
| Nombre científico | Anser caerulescens | Heteronetta atricapilla |
| Orden | Anseriformes | Anseriformes |
| Familia | Anatidae | Anatidae |
| Estado de conservación | Least Concern | Least Concern |
| Longitud | — | — |
| Envergadura | 82,4 cm (32.4 in) | 34,7 cm (13.7 in) |
| Peso | 2561,0 g (90.34 oz) | 528,5 g (18.64 oz) |
| Dieta | Grazes submerged aquatic vegetation and eelgrass in estuaries; also takes grasses and sedges on coastal … | Parasitic; adults may feed on aquatic plants, seeds, and invertebrates in South American marshes. Diet … |
| Tamaño de la puesta | 2-6 | 2 |
| Population Trend | — | — |
Habitat Comparison
Hábitats compartidos
Snow Goose only
Black-headed Duck only
Ninguno
Snow Goose
Breeds on coastal and inland Arctic tundra in Canada, Alaska, and Greenland. Winters on agricultural fields, marshes, and coastal wetlands across the United States and northern Mexico. Forms enormous flocks.
Song & Call Comparison
Snow Goose
A loud, nasal barking 'luk-luk' or 'kow-kow'. Large flocks create enormous noise during Arctic nesting and winter staging. Considered a noisy, conspicuous goose.
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.
Geographic Range & Migration
Snow Goose
Breeds in eastern North America's boreal forest; winters on the Atlantic coast from New England to South Carolina.
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.
Estado de conservación
Snow Goose
Black-headed Duck
How to Tell Them Apart
Snow Goose
White morph: pure white plumage with black primaries and pink bill and legs. Blue morph: dark blue-gray body with white head. Both morphs interbreed freely. 'Grinning patch' on bill. Sexes …
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.
About These Birds
Snow Goose
El ganso de las nieves es un ganso ártico que se presenta en dos morfologías de color: una forma blanca con las puntas de las alas negras y una forma azul-grisácea. Cría en la tundra ártica y migra en enormes bandadas al sur de Estados Unidos y México para pasar el invierno. Sus poblaciones han aumentado explosivamente en las últimas décadas, causando problemas de sobrepastoreo en la tundra.
Black-headed Duck
El pato cabeza negra es un pequeño pato buceador (~530 g) de América del Sur, familia Anatidae, y el único miembro del género Heteronetta. Tiene la cabeza negra en el macho y cuerpo marrón. Parásita de nido obligada: pone sus huevos en los nidos de otras aves acuáticas, especialmente fochas y pollas de agua. Habita en lagos y lagunas con vegetación emergente de Argentina, Bolivia, Brasil, Chile, Paraguay y Uruguay. No cría su propia cría nunca.