Auckland Teal vs Black-headed Duck
Anas aucklandica 比較対象 Heteronetta atricapilla
Side-by-Side Comparison
| 属性 | Auckland Teal | Black-headed Duck |
|---|---|---|
| 学名 | Anas aucklandica | Heteronetta atricapilla |
| 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) | 34.7 cm (13.7 in) |
| 体重 | 522.25 g (18.42 oz) | 528.5 g (18.64 oz) |
| 食性 | Dives for molluscs, crustaceans, and aquatic invertebrates; diet dominated by hard-shelled prey in coastal habitats. | Parasitic; adults may feed on aquatic plants, seeds, and invertebrates in South American marshes. Diet … |
| 一腹卵数 | 1-6 | 2 |
| 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.
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.
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
Auckland Teal
Breeds in Arctic and sub-Arctic North America; winters on Pacific and Atlantic coasts south to California and the Carolinas.
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
Auckland Teal
Black-headed 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.
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
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。
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。