Snow Goose vs Black-headed Duck
Anser caerulescens 对比 Heteronetta atricapilla
Side-by-Side Comparison
| 属性 | Snow Goose | Black-headed Duck |
|---|---|---|
| 学名 | Anser caerulescens | Heteronetta atricapilla |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保护状况 | Least Concern | Least Concern |
| 体长 | — | — |
| 翼展 | 82.4 cm (32.4 in) | 34.7 cm (13.7 in) |
| 体重 | 2561.0 g (90.34 oz) | 528.5 g (18.64 oz) |
| 食性 | 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 … |
| 产卵数 | 2-6 | 2 |
| Population Trend | — | — |
Habitat Comparison
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.
保护状况
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
雪雁是北美数量最多的雁类之一，繁殖于加拿大北极苔原，越冬于美国南部及墨西哥湾沿岸。有白色和蓝色两种色型，白色型全身白色，翼尖黑色；蓝色型身体灰褐色，头颈白色。迁徙时常形成壮观的数十万只大群，以草地和农田植物为食。
Black-headed Duck
黑头鸭是南美洲的寄生性鸭子，不自己筑巢，而将卵产于其他水鸟（包括其他鸭类、䴙䴘、红鹭等）的巢中，由寄主孵化并抚育。分布于阿根廷、乌拉圭、智利和巴西南部。雄鸟头部黑色，体羽深褐色；雌鸟头部褐色。是唯一真正的全职巢寄生鸭类。