Hawaiian Duck vs Black-headed Duck
Anas wyvilliana 比較対象 Heteronetta atricapilla
Side-by-Side Comparison
| 属性 | Hawaiian Duck | Black-headed Duck |
|---|---|---|
| 学名 | Anas wyvilliana | Heteronetta atricapilla |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Vulnerable | Least Concern |
| 体長 | — | — |
| 翼開長 | 44.0 cm (17.3 in) | 34.7 cm (13.7 in) |
| 体重 | 573.25 g (20.22 oz) | 528.5 g (18.64 oz) |
| 食性 | Fish-diving duck of South American rivers; uses serrated bill to catch fish and aquatic invertebrates; … | Parasitic; adults may feed on aquatic plants, seeds, and invertebrates in South American marshes. Diet … |
| 一腹卵数 | 9-13 | 2 |
| Population Trend | — | — |
Habitat Comparison
Hawaiian Duck
Freshwater marshes, rivers, reservoirs, and taro fields on Kauai and other Hawaiian islands. Nests in dense vegetation near water. Threatened by hybridization with domestic or feral Mallards.
Song & Call Comparison
Hawaiian Duck
Female produces a raspy, descending quacking series; male gives a soft, nasal sound. Calls similar to Mallard but higher-pitched; alarm is a rapid-fire quacking rattle.
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
Hawaiian Duck
Ranges across sub-Saharan Africa in open grasslands and wetland edges. Locally nomadic following seasonal rainfall patterns.
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
Hawaiian Duck
Black-headed Duck
How to Tell Them Apart
Hawaiian Duck
Mottled brown plumage; males may show slight green gloss on head but reduced compared to Mallard. Iridescent blue-purple speculum with white borders. Orange bill. Females similar to males; pale buff …
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
Hawaiian Duck
ハワイガモはハワイ諸島固有の絶滅危惧種のカモです。マガモに近縁で、雄は緑色の頭部を持ちますが、より地味な外見をしています。湿地や川、池などに生息し、水生植物や無脊椎動物を食べます。外来捕食者や生息地の喪失が主な脅威となっています。
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。