American Black Duck vs Common Shelduck
Anas rubripes 比較対象 Tadorna tadorna
Side-by-Side Comparison
| 属性 | American Black Duck | Common Shelduck |
|---|---|---|
| 学名 | Anas rubripes | Tadorna tadorna |
| 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) | 62.8 cm (24.7 in) |
| 体重 | 1211.25 g (42.73 oz) | 1035.5 g (36.53 oz) |
| 食性 | Eats fish and aquatic invertebrates; dives in coastal and freshwater habitats; diet shifts toward molluscs … | Eats seeds, leaves, and aquatic invertebrates; dabbles in shallow water; diet broadly omnivorous and varies … |
| 一腹卵数 | 1-17 | 3-18 |
| 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.
Common Shelduck
Coastal estuaries, mudflats, saltmarshes, sand dunes, and inland saline lakes from northwest Europe east across Eurasia to China. Winters mainly on tidal estuaries and coastal wetlands. Nests in burrows.
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.
Common Shelduck
Male gives a whistled 'wheee'; female gives a cackling series of rapid nasal 'ak-ak-ak' notes. One of the most sexually dimorphic calls of any shelduck species.
Geographic Range & Migration
American Black Duck
Breeds in the steppe zone of Central Asia; winters in South Asia, East Africa, and coastal Southeast Asia.
Common Shelduck
Breeds in Siberian tundra; winters in eastern and southern Africa, and in South and Southeast Asia. Trans-hemispheric migrant.
保全状況
American Black Duck
Common 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 …
Common Shelduck
White body with dark green head, broad chestnut breastband, and black scapular stripes. Red bill with basal knob in males. Green speculum and black wingtips. Underparts white with black belly …
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。
Common Shelduck
西ヨーロッパから中央アジアにかけての塩性干潟・砂浜に生息するカモ（体長58〜67cm）。白・黒・緑・赤褐色の鮮やかな羽模様と雄の赤いこぶ付き嘴が特徴的。Tadorna tadorna（ツクシガモ）は地上の穴に営巣し、ウミホタルなどの微小な生物を泥の中からこし取る。日本では迷鳥として稀に観察される。Anatidae科。