Hardhead vs African Pygmy-goose
Aythya australis 比較対象 Nettapus auritus
Side-by-Side Comparison
| 属性 | Hardhead | African Pygmy-goose |
|---|---|---|
| 学名 | Aythya australis | Nettapus auritus |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Least Concern | Least Concern |
| 体長 | — | — |
| 翼開長 | 42.7 cm (16.8 in) | 29.9 cm (11.8 in) |
| 体重 | 803.75 g (28.35 oz) | 272.5 g (9.61 oz) |
| 食性 | Dives for molluscs, crustaceans, and aquatic invertebrates in coastal habitats; diet shifts between invertebrate types … | Filter-feeds on invertebrates and seeds; dabbles in shallow ponds; diet more plant-based outside spring breeding … |
| 一腹卵数 | 6-18 | 6-12 |
| Population Trend | — | — |
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.
African Pygmy-goose
Freshwater lakes, ponds, and rivers with floating water lilies and other aquatic vegetation across sub-Saharan Africa from Senegal to Tanzania. Nests in tree cavities near water. Highly dependent on water lily vegetation.
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.
African Pygmy-goose
Male produces a soft, wheezy whistle; female gives a quiet, duck-like quack. Pairs exchange rapid twittering notes during courtship on lily-covered African pools.
Geographic Range & Migration
Hardhead
Breeds in northern prairie potholes; winters along the Pacific coast of North America from British Columbia to Baja California.
African Pygmy-goose
Breeds across temperate to sub-Arctic Eurasia; winters in Africa, South Asia, and Southeast Asia.
保全状況
Hardhead
African Pygmy-goose
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 …
African Pygmy-goose
Tiny. Males have glossy dark green head with orange facial patch and ear spot; chestnut-orange flanks; white underparts; black and green back. Females duller with dark eye-stripe. Small yellow-green bill.
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。
African Pygmy-goose
アフリカンピグミーグースはアフリカ南部と東部に分布する小型の木巣性カモです。雄の緑と栗色の美しい羽毛と小さなサイズが特徴的です。水草が豊富な湖や沼地に生息し、蓮や水草の種子を主食とします。木の洞に営巣します。