Black-headed Duck vs Ruddy Duck
Heteronetta atricapilla 比較対象 Oxyura jamaicensis
Side-by-Side Comparison
| 属性 | Black-headed Duck | Ruddy Duck |
|---|---|---|
| 学名 | Heteronetta atricapilla | Oxyura jamaicensis |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Least Concern | Least Concern |
| 体長 | — | — |
| 翼開長 | 34.7 cm (13.7 in) | 27.9 cm (11.0 in) |
| 体重 | 528.5 g (18.64 oz) | 586.6666666666666 g (20.69 oz) |
| 食性 | Parasitic; adults may feed on aquatic plants, seeds, and invertebrates in South American marshes. Diet … | Dives for aquatic plant seeds, roots, and invertebrates in freshwater marshes. Uses stiff tail as … |
| 一腹卵数 | 2 | 5-15 |
| 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.
Ruddy Duck
Male produces a mechanical, drumming bok-bok-bok staccato beat; female gives a harsh, nasal quack. The male's rapid drum-roll call on the bill during display is startlingly loud and distinctive.
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.
Ruddy Duck
Breeds across interior North America from western Canada south to Mexico. Winters on coasts and inland waters south to northern South America.
保全状況
Black-headed Duck
Ruddy Duck
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.
Ruddy Duck
Breeding male has vivid rufous-chestnut body, black crown, white cheeks, and bright sky-blue bill; stiff tail often cocked upright. Female is dull brown with pale cheek crossed by single dark …
About These Birds
Black-headed Duck
クロアタマカモはアルゼンチン・チリ・ウルグアイ・ブラジル南部の南アメリカ温帯湖沼・湿地に生息する托卵性のカモ（体長32〜35 cm）。雄は黒い頭と薄い茶色の体が特徴。他のカモ・コオット・ヒクイナの巣に托卵する。育雛しない数少ない水禽の一つ。
Ruddy Duck
北米で繁殖し、中米・南米北部で越冬する小型の潜水ガモ（体長35〜43cm）。雄の繁殖羽は栗色の体に白い頬、青い嘴が特徴的。Oxyura jamaicensis（ルディダック）は特徴的な扇状の尾羽を立てる姿勢で知られる。北米原産だがヨーロッパに移入・定着し、近縁のフェルギネオウ・ホワイトヘッドダックとの交雑が問題となっている。Anatidae科。