Torrent Duck vs African Pygmy-goose
Merganetta armata 比較対象 Nettapus auritus
Side-by-Side Comparison
| 属性 | Torrent Duck | African Pygmy-goose |
|---|---|---|
| 学名 | Merganetta armata | Nettapus auritus |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Least Concern | Least Concern |
| 体長 | — | — |
| 翼開長 | 32.7 cm (12.9 in) | 29.9 cm (11.8 in) |
| 体重 | 366.875 g (12.94 oz) | 272.5 g (9.61 oz) |
| 食性 | Filter-feeds on aquatic invertebrates and seeds; dabbles in shallow wetlands; diet more plant-based in winter … | Filter-feeds on invertebrates and seeds; dabbles in shallow ponds; diet more plant-based outside spring breeding … |
| 一腹卵数 | 3-4 | 6-12 |
| Population Trend | — | — |
Habitat Comparison
Torrent Duck
Fast-flowing clear Andean mountain rivers and torrents at 1,500–4,500 m from Venezuela south through Colombia, Ecuador, Peru, Bolivia, and Chile to Tierra del Fuego. Requires bouldered well-oxygenated rapids.
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
Torrent Duck
A sharp, staccato 'pit' or 'wit' call. Males give a loud, ringing whistle. The Torrent Duck is a fast-flowing Andean river specialist; calls carry over powerful rapids.
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
Torrent Duck
Breeds in the northern prairie pothole region; winters along both coasts of the United States and south to Mexico.
African Pygmy-goose
Breeds across temperate to sub-Arctic Eurasia; winters in Africa, South Asia, and Southeast Asia.
保全状況
Torrent Duck
African Pygmy-goose
How to Tell Them Apart
Torrent Duck
Striking sexual dimorphism. Males have white head with black stripes and red bill; dark back with rufous breast. Females gray above with rufous-cinnamon underparts. Stiff tail; specialized for fast-running rivers.
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
Torrent Duck
トレンツアイサはアンデス山脈の急流河川に生息する特殊なカモです。水流の速い清澄な渓流に適応しており、流れの中の岩の上を歩き回ります。魚、水生昆虫、甲殻類を捕食します。厳しい流れに適応した独特の生態を持ちます。
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。