Eastern Spot-billed Duck vs Brent Goose
Anas zonorhyncha 比較対象 Branta bernicla
Side-by-Side Comparison
| 属性 | Eastern Spot-billed Duck | Brent Goose |
|---|---|---|
| 学名 | Anas zonorhyncha | Branta bernicla |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Least Concern | Least Concern |
| 体長 | — | — |
| 翼開長 | 53.6 cm (21.1 in) | 63.9 cm (25.2 in) |
| 体重 | 1017.5 g (35.89 oz) | 1335.0 g (47.09 oz) |
| 食性 | Eats fish, aquatic invertebrates, and amphibians; dives in freshwater rivers; serrated bill grips prey; fish … | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … |
| 一腹卵数 | 7-9 | 1-10 |
| Population Trend | — | — |
Habitat Comparison
Eastern Spot-billed Duck
Freshwater lakes, rivers, marshes, and rice paddies in northeastern Asia from eastern Russia and Siberia through China, Korea, and Japan. Winters in southern China and southern Japan.
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.
Song & Call Comparison
Eastern Spot-billed Duck
Female produces a loud, descending quacking series; male gives a low, nasal grunt. Vocalizations closely resemble the Indian Spot-billed Duck; pairs call antiphonally on East Asian wetlands.
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.
Geographic Range & Migration
Eastern Spot-billed Duck
Found in wetlands across Southeast Asia, from India to China, Vietnam, and Indonesia. Largely resident; local seasonal movements.
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
保全状況
Eastern Spot-billed Duck
Brent Goose
How to Tell Them Apart
Eastern Spot-billed Duck
Brown body with pale buff face and throat; dark crown and eye stripe. Yellow-tipped black bill lacking the red spot of Indian Spot-billed Duck. Iridescent green speculum with white border. …
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.
About These Birds
Eastern Spot-billed Duck
オナガガモに似たこのカモは東アジアに分布し、中国、ロシア極東、日本などに生息します。嘴に黄色い斑点があるのが特徴で、湿地や水田、池に生息します。冬季には暖かい地方に渡りますが、一部は通年同じ地域に留まります。
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。