American Black Duck vs Crested Shelduck
Anas rubripes 比較対象 Tadorna cristata
Side-by-Side Comparison
| 属性 | American Black Duck | Crested Shelduck |
|---|---|---|
| 学名 | Anas rubripes | Tadorna cristata |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Least Concern | Critically Endangered |
| 体長 | — | — |
| 翼開長 | 53.4 cm (21.0 in) | 59.8 cm (23.5 in) |
| 体重 | 1211.25 g (42.73 oz) | 1235.0 g (43.56 oz) |
| 食性 | Eats fish and aquatic invertebrates; dives in coastal and freshwater habitats; diet shifts toward molluscs … | Possibly extinct; Crested Shelduck fed on seeds, aquatic plants, and invertebrates near East Asian wetlands; … |
| 一腹卵数 | 1-17 | 10 |
| 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.
Crested Shelduck
Historically known from coastal Korea, Siberia, and possibly Japan. Habitat preferences poorly known; specimens were collected near coasts and rivers. Possibly extinct.
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.
Crested Shelduck
Critically endangered; last confirmed sightings in 1971. No vocalizations reliably recorded. Presumed similar to related shelducks based on phylogeny but effectively unknown.
Geographic Range & Migration
American Black Duck
Breeds in the steppe zone of Central Asia; winters in South Asia, East Africa, and coastal Southeast Asia.
Crested Shelduck
Breeds across the Palearctic; winters from West Africa to South Africa. Uses the western and central Palearctic–African flyways.
保全状況
American Black Duck
Crested Shelduck
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 …
Crested Shelduck
Critically rare; known from few specimens. Males dark green head with bushy crest; black and white body with chestnut flanks. Females have white facial markings and brown-barred body. Possibly extinct; …
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。
Crested Shelduck
カンムリツクシガモは韓国と中国の一部に生息したとされる幻の鳥で、現在は絶滅したと考えられています。雄は緑色の羽毛と特徴的な冠羽を持っていました。20世紀初頭以降の確認記録がなく、生態はほとんど不明です。