Auckland Teal vs American Black Duck
Anas aucklandica 比較対象 Anas rubripes
Side-by-Side Comparison
| 属性 | Auckland Teal | American Black Duck |
|---|---|---|
| 学名 | Anas aucklandica | Anas rubripes |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Near Threatened | Least Concern |
| 体長 | — | — |
| 翼開長 | 27.0 cm (10.6 in) | 53.4 cm (21.0 in) |
| 体重 | 522.25 g (18.42 oz) | 1211.25 g (42.73 oz) |
| 食性 | Dives for molluscs, crustaceans, and aquatic invertebrates; diet dominated by hard-shelled prey in coastal habitats. | Eats fish and aquatic invertebrates; dives in coastal and freshwater habitats; diet shifts toward molluscs … |
| 一腹卵数 | 1-6 | 1-17 |
| Population Trend | — | — |
Habitat Comparison
Auckland Teal
Restricted to predator-free islands of the Auckland Islands subantarctic group (Adams, Disappointment, Ewing islands). Inhabits dense tussock grassland, scrub, and freshwater streams.
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.
Song & Call Comparison
Auckland Teal
Female gives a short, nasal quack; male produces a barely audible high note. Nearly flightless; extremely quiet and seldom vocal; calls are reduced even compared with other flightless island teals.
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.
Geographic Range & Migration
Auckland Teal
Breeds in Arctic and sub-Arctic North America; winters on Pacific and Atlantic coasts south to California and the Carolinas.
American Black Duck
Breeds in the steppe zone of Central Asia; winters in South Asia, East Africa, and coastal Southeast Asia.
保全状況
Auckland Teal
American Black Duck
How to Tell Them Apart
Auckland Teal
Dark chocolate-brown plumage; males have iridescent dark green head and white eye-ring. Females dark brown with white eye-ring. Near-flightless. Iridescent speculum. Flightless wings. Auckland Islands endemic.
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 …
About These Birds
Auckland Teal
オークランドティールはニュージーランドのオークランド諸島に固有の飛べないカモです。マガモから進化した島嶼固有種で、翼が退化して飛行能力を失っています。島の森林内の池や小川に生息し、無脊椎動物、植物、種子などを採食します。外来捕食者の排除が保全の鍵です。
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。