Laysan Duck vs Black Swan
Anas laysanensis 比較対象 Cygnus atratus
Side-by-Side Comparison
| 属性 | Laysan Duck | Black Swan |
|---|---|---|
| 学名 | Anas laysanensis | Cygnus atratus |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Critically Endangered | Least Concern |
| 体長 | — | 130.0 cm (51.2 in) |
| 翼開長 | 39.7 cm (15.6 in) | 190.0 cm (74.8 in) |
| 体重 | 465.25 g (16.41 oz) | 6200.0 g (218.70 oz) |
| 食性 | Dives for small fish, aquatic invertebrates, and amphibians; serrated bill grips prey; diet fish-heavy in … | Aquatic vegetation and algae, supplemented with grain and pasture grasses. Feeds by upending in shallow … |
| 一腹卵数 | 9-13 | 4-6 |
| Population Trend | — | — |
Size Comparison
Habitat Comparison
Laysan Duck
Restricted to Laysan Island and Midway Atoll in the Hawaiian Islands. Inhabits the central hypersaline lagoon and surrounding vegetation. Feeds on brine shrimp and flies around the lagoon margin.
Black Swan
Lakes, rivers, swamps, and coastal waters across Australia. Also found in ornamental lakes in parks.
Song & Call Comparison
Laysan Duck
Female gives a soft, muffled quacking series; male utters a quiet rasp. Extremely rare; the soft, unobtrusive quacking calls are seldom heard on the remote Laysan Island lagoon.
Black Swan
Gives a musical bugling 'boo-boo-boo' in flight and softer honking on water. Less vocal than Mute Swan; produces a baying call when alarmed. Wings whistle softly in flight.
Geographic Range & Migration
Laysan Duck
Resident in West Africa from Senegal to Nigeria; inhabits rainforest streams and swamps. Sedentary and locally common.
Black Swan
Australia, primarily in the southeast and southwest. Introduced populations in New Zealand, Japan, and western Europe.
保全状況
Laysan Duck
Black Swan
How to Tell Them Apart
Laysan Duck
Brown plumage mottled and streaked buff and dark brown. White eye-ring contrasts with dark face. Both sexes similar; females show reduced white eye ring. Iridescent speculum. Critically endangered; only on …
Black Swan
Almost entirely black with white flight feathers visible in flight. Red bill with a white band near the tip. Dark red to reddish-brown iris.
Bright red bill with a pale tip and prominent white band
About These Birds
Laysan Duck
レイサンガモはハワイのレイサン島にのみ生息する極めて希少な固有種です。マガモから進化したと考えられており、翼に白い斑点があるのが特徴です。かつて絶滅の危機に瀕していましたが、保全活動により個体数が回復しています。飛翔能力は持ちますが、主に地上を歩いて採食します。
Black Swan
コクチョウはかつてすべての白鳥は白いと信じていたヨーロッパ人に不可能と考えられており、帰納的推論の失敗の有名な哲学的な例となっている。西オーストラリア州の州の鳥。コクチョウは生涯続く番いの絆を形成し、両親が共同で抱卵と雛の世話を行う。