Hardhead vs Black Swan
Aythya australis 比較対象 Cygnus atratus
Side-by-Side Comparison
| 属性 | Hardhead | Black Swan |
|---|---|---|
| 学名 | Aythya australis | Cygnus atratus |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Least Concern | Least Concern |
| 体長 | — | 130.0 cm (51.2 in) |
| 翼開長 | 42.7 cm (16.8 in) | 190.0 cm (74.8 in) |
| 体重 | 803.75 g (28.35 oz) | 6200.0 g (218.70 oz) |
| 食性 | Dives for molluscs, crustaceans, and aquatic invertebrates in coastal habitats; diet shifts between invertebrate types … | Aquatic vegetation and algae, supplemented with grain and pasture grasses. Feeds by upending in shallow … |
| 一腹卵数 | 6-18 | 4-6 |
| Population Trend | — | — |
Size Comparison
Habitat Comparison
Hardhead
Deep freshwater lakes, rivers, and reservoirs across Australia and New Guinea. Nomadic in Australia, following seasonal inland flooding. Prefers deep water with submerged aquatic plants.
Black Swan
Lakes, rivers, swamps, and coastal waters across Australia. Also found in ornamental lakes in parks.
Song & Call Comparison
Hardhead
Male produces a deep, purring wheeze; female gives a grating quacking series. Calls closely resemble Common Pochard; the female's harsh notes carry far across Australian freshwater lakes.
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
Hardhead
Breeds in northern prairie potholes; winters along the Pacific coast of North America from British Columbia to Baja California.
Black Swan
Australia, primarily in the southeast and southwest. Introduced populations in New Zealand, Japan, and western Europe.
保全状況
Hardhead
Black Swan
How to Tell Them Apart
Hardhead
Males dark chocolate-brown with white undertail and flanks. White eye conspicuous. Blue-gray bill with white band and black tip. Females similar but brown with brown eye. Bold white wing stripe …
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
Hardhead
オーストラリアンホワイトアイはオーストラリアとニュージーランドに分布する潜水性カモです。雄は栗色の頭部と赤い目が特徴的です。水草が豊富な深い湿地や湖に生息し、水に潜って水草の塊茎や根を採食します。オーストラリアでは比較的普通に見られる種です。
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。