American Black Duck vs Gadwall
Anas rubripes 比較対象 Mareca strepera
Side-by-Side Comparison
| 属性 | American Black Duck | Gadwall |
|---|---|---|
| 学名 | Anas rubripes | Mareca strepera |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Least Concern | Least Concern |
| 体長 | — | — |
| 翼開長 | 53.4 cm (21.0 in) | 50.3 cm (19.8 in) |
| 体重 | 1211.25 g (42.73 oz) | 857.5 g (30.25 oz) |
| 食性 | Eats fish and aquatic invertebrates; dives in coastal and freshwater habitats; diet shifts toward molluscs … | Dabbles for seeds and aquatic invertebrates; diet shifts toward invertebrates in spring; forages in shallow … |
| 一腹卵数 | 1-17 | 5-15 |
| Population Trend | — | — |
Habitat Comparison
American Black Duck
Freshwater and brackish wetlands in eastern North America from Atlantic Canada south along the coast to Georgia. Breeds in northern bogs and wetlands. Winters on coastal marshes, estuaries, and freshwater lakes.
Gadwall
Freshwater lakes, reservoirs, marshes, and rivers with emergent vegetation across Eurasia and North America. Winters on large open wetlands and coastal estuaries. Range and population increasing in Europe.
Song & Call Comparison
American Black Duck
Female produces a loud, deep quacking series; male gives a low, raspy grunt. Voice is deeper and huskier than a Mallard; pairs call powerfully across northeastern North American wetlands.
Gadwall
Male utters a soft, nasal nheck note; female produces a series of descending, quacking notes. Both sexes are relatively quiet; female's quacking is softer and less strident than a Mallard.
Geographic Range & Migration
American Black Duck
Breeds in the steppe zone of Central Asia; winters in South Asia, East Africa, and coastal Southeast Asia.
Gadwall
Found year-round in Australia and New Zealand; nomadic in arid Australia, following temporary rainfall-fed wetlands.
保全状況
American Black Duck
Gadwall
How to Tell Them Apart
American Black Duck
Sooty dark brown body; head and neck paler buff with dark streaking. Iridescent purple speculum without white border. Males have yellow-green bill; females olive with orange blotches. Silvery underwings in …
Gadwall
Males have finely vermiculated gray-brown plumage with black rump and undertail. White speculum patch diagnostic in flight. Females mottled brown like Mallard but smaller and with orange-sided bill. Subtle but …
About These Birds
American Black Duck
北米東部の湿地、沼、河川に生息するカモ（体長53〜61cm）。全体的に暗褐色でマガモの雌に似るが、嘴の色や翼鏡の色が異なる。Anas rubripes（アメリカクロガモ）は海岸の塩性湿地から内陸の淡水域まで幅広く利用し、マガモとの雑種が多く観察される。Anatidae科。
Gadwall
カドワール。ユーラシア大陸と北アメリカに広く分布するカモ。雄は灰褐色の体と黒い尾部が特徴的。体長46〜56cm。湖や池、湿地に生息。植物性の食物を好む雑食性。北半球で繁殖し南へ渡る。低危険種。