Brent Goose vs Rosy-billed Pochard
Branta bernicla 比較対象 Netta peposaca
Side-by-Side Comparison
| 属性 | Brent Goose | Rosy-billed Pochard |
|---|---|---|
| 学名 | Branta bernicla | Netta peposaca |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Least Concern | Least Concern |
| 体長 | — | — |
| 翼開長 | 63.9 cm (25.2 in) | 46.1 cm (18.1 in) |
| 体重 | 1335.0 g (47.09 oz) | 1103.4 g (38.92 oz) |
| 食性 | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … | Eats molluscs, crustaceans, and aquatic invertebrates; dives in shallow coastal water; diet dominated by invertebrates. |
| 一腹卵数 | 1-10 | 10 |
| Population Trend | — | — |
Habitat Comparison
Brent Goose
Breeds on high-Arctic tundra; winters on estuaries, coastal mudflats, saltmarshes, and sea-grass beds along Atlantic and Pacific coastlines. One of the most strictly coastal wintering geese.
Rosy-billed Pochard
Freshwater lakes, marshes, and lagoons in southern South America from central Brazil through Bolivia, Uruguay, and Argentina to Patagonia. Often on large open lakes. Partially migratory; moves northward in winter.
Song & Call Comparison
Brent Goose
A low, guttural 'rronk' or 'ronk-ronk' from flocks. Soft nasal calls in feeding groups. A subtle, understated call for a goose — less loud than most Anser geese.
Rosy-billed Pochard
Male gives a deep, burping boom; female produces a loud, grunting quack. The male's resonant booming call during display is among the most powerful calls of South American wildfowl.
Geographic Range & Migration
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
Rosy-billed Pochard
Breeds in northern prairies; winters on interior wetlands and coasts from the southern US to Central America.
保全状況
Brent Goose
Rosy-billed Pochard
How to Tell Them Apart
Brent Goose
Small; mostly black head, neck, and breast. Small white neck-patch on adults. Back dark brownish-gray; belly pale gray to white depending on subspecies. White undertail coverts. Sexes similar.
Rosy-billed Pochard
Males dark sooty-black with iridescent purple gloss on head; bright rosy-red bill with pink knob. White flanks visible when at rest. Females brown with pale face and gray bill. Bold …
About These Birds
Brent Goose
北極圏で繁殖し、北半球の海岸で越冬する小型のガン（体長55〜66cm）。黒い頭・首・胸に短い白い首輪が特徴。Branta bernicla（コクガン）は主にアマモなどの海草を食べ、干潟や浅い入り江を好む。日本でも北海道・東北の海岸で越冬する姿が見られ、個体数は比較的少ない。Anatidae科。
Rosy-billed Pochard
ローズビルドポチャードは南米南部に分布する潜水性カモです。雄は鮮やかなピンクの嘴と黒白の体が特徴的です。アルゼンチン、チリ、ブラジル南部の草原地帯の湖や湿地に生息し、水草や無脊椎動物を潜って採食します。