Black-headed Duck vs Radjah Shelduck
Heteronetta atricapilla 对比 Radjah radjah
Side-by-Side Comparison
| 属性 | Black-headed Duck | Radjah Shelduck |
|---|---|---|
| 学名 | Heteronetta atricapilla | Radjah radjah |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保护状况 | Least Concern | Least Concern |
| 体长 | — | — |
| 翼展 | 34.7 cm (13.7 in) | 54.0 cm (21.3 in) |
| 体重 | 528.5 g (18.64 oz) | 883.5 g (31.16 oz) |
| 食性 | Parasitic; adults may feed on aquatic plants, seeds, and invertebrates in South American marshes. Diet … | Dabbles for seeds and aquatic invertebrates; also grazes on grasses; diet shifts between land and … |
| 产卵数 | 2 | 6-15 |
| Population Trend | — | — |
Habitat Comparison
Radjah Shelduck
Mangroves, tidal mudflats, tropical coastal wetlands, and freshwater lagoons in New Guinea and the tropical north of Australia (Queensland, Northern Territory, Western Australia). Nests in tree hollows near water.
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.
Radjah Shelduck
A loud, rattling 'radjah-radjah' or repeated cackling 'rak-rak-rak'. Calls from tropical Australian and New Guinea wetlands. Name is partly onomatopoeic.
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.
Radjah Shelduck
Breeds in the eastern Arctic of Russia; winters across southern Asia, from the Indian subcontinent to Southeast Asia.
保护状况
Black-headed Duck
Radjah Shelduck
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.
Radjah Shelduck
White head and body with chestnut breastband and white-spotted chestnut scapulars. Pink bill and legs. Iridescent green speculum with white bar visible in flight. Sexes similar. Australasian mangrove specialist.
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。
Radjah Shelduck
澳大利亚贝壳鸭（披肩雁鸭）是澳大利亚北部和新几内亚特有的大型鸭子。体型粗壮，头颈白色，胸部有栗褐色胸带，背部黑色，翼上有绿色翼镜。栖息于热带海岸红树林、淡水湿地和河流。以软体动物、甲壳类、昆虫和植物为食，在树洞中营巢。