Hardhead vs Spotted Whistling-duck
Aythya australis 比較対象 Dendrocygna guttata
Side-by-Side Comparison
| 属性 | Hardhead | Spotted Whistling-duck |
|---|---|---|
| 学名 | Aythya australis | Dendrocygna guttata |
| 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) | 41.3 cm (16.3 in) |
| 体重 | 803.75 g (28.35 oz) | 677.5 g (23.90 oz) |
| 食性 | Dives for molluscs, crustaceans, and aquatic invertebrates in coastal habitats; diet shifts between invertebrate types … | Primarily herbivorous; grazes tundra grasses and sedges; winters on coastal marshes and farmland, switching to … |
| 一腹卵数 | 6-18 | 10-11 |
| 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.
Spotted Whistling-duck
Freshwater wetlands, rice fields, streams, and forest pools in New Guinea, Sulawesi, the Philippines, and Moluccas. Often found near forested rivers and seasonal swamps at low elevations.
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.
Spotted Whistling-duck
A musical, high whistle similar to other whistling-ducks. Call is softer and less far-carrying than White-faced or Black-bellied species. Given in flight and on water.
Geographic Range & Migration
Hardhead
Breeds in northern prairie potholes; winters along the Pacific coast of North America from British Columbia to Baja California.
Spotted Whistling-duck
Ranges widely across sub-Saharan Africa in open woodland and savanna. Largely sedentary with local seasonal movements to water.
保全状況
Hardhead
Spotted Whistling-duck
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 …
Spotted Whistling-duck
Dark brown above; head and neck dark brown. Underparts heavily spotted white on dark brown ground, giving spotted appearance. Flanks with bold white spots. Pink-red bill and legs. Sexes similar.
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。
Spotted Whistling-duck
スポッテドウィスリングダックはインドネシア、フィリピン、パプアニューギニアに分布するツリーダックです。白い斑点のある褐色の羽毛が特徴で、夜間に特徴的な笛のような声でさえずります。熱帯の湿地、稲田、マングローブ林に生息し、草の種子や水草を採食します。