Snow Goose vs Black-headed Duck
Anser caerulescens 比較対象 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 |
| 保全状況 | Least Concern | Least Concern |
| 体長 | — | — |
| 翼開長 | 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 … |
| 一腹卵数 | 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.
保全状況
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
北極圏（カナダ、シベリア）で繁殖し、北米南部や東アジアで越冬するガン（体長64〜79cm）。白色型と青灰色型（ブルーグース）の2つの色彩型がある。Anser caerulescens（ハクガン）は渡りの際に何百万羽もの大群を形成することで知られ、農業地帯での農作物被害が問題になることもある。Anatidae科。
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。