Black-headed Duck vs Spectacled Eider
Heteronetta atricapilla 对比 Somateria fischeri
Side-by-Side Comparison
| 属性 | Black-headed Duck | Spectacled Eider |
|---|---|---|
| 学名 | Heteronetta atricapilla | Somateria fischeri |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保护状况 | Least Concern | Near Threatened |
| 体长 | — | — |
| 翼展 | 34.7 cm (13.7 in) | 49.2 cm (19.4 in) |
| 体重 | 528.5 g (18.64 oz) | 1443.75 g (50.93 oz) |
| 食性 | Parasitic; adults may feed on aquatic plants, seeds, and invertebrates in South American marshes. Diet … | Dives for bivalves, crustaceans, and aquatic insects in shallow Arctic coastal and freshwater habitats. Insects … |
| 产卵数 | 2 | 1-9 |
| 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.
Spectacled Eider
Male gives a low, melodious aah-ooo cooing; female produces a guttural, grunting call. The male's ghostly, organ-like cooing call carries across Arctic tundra ponds in the breeding season.
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.
Spectacled Eider
Breeds on coastal tundra of western and northern Alaska. Winters along the Bering Sea coast from Alaska to Kamchatka. Largely sedentary.
保护状况
Black-headed Duck
Spectacled Eider
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.
Spectacled Eider
Male has white back and black breast with pale sage-green head framed by large white goggle-like spectacles edged black. Female mottled tawny-brown with faint spectacle outline.
About These Birds
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。
Spectacled Eider
A medium-large sea duck of the family Anatidae, weighing ~1.4 kg with distinctive pale green goggles in males. Breeds on Arctic tundra of Alaska and Russia; winters in pack ice of the Bering Sea. Dives for benthic invertebrates and mollusks. Near Threatened due to population declines linked to lead poisoning and habitat change.