Ferruginous Duck vs Brent Goose
Aythya nyroca 比較対象 Branta bernicla
Side-by-Side Comparison
| 属性 | Ferruginous Duck | Brent Goose |
|---|---|---|
| 学名 | Aythya nyroca | Branta bernicla |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Near Threatened | Least Concern |
| 体長 | — | — |
| 翼開長 | 36.5 cm (14.4 in) | 63.9 cm (25.2 in) |
| 体重 | 594.1666666666666 g (20.96 oz) | 1335.0 g (47.09 oz) |
| 食性 | Eats molluscs, crustaceans, and aquatic invertebrates; dives in coastal habitats; diet dominated by hard-shelled invertebrates. | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … |
| 一腹卵数 | 4-17 | 1-10 |
| Population Trend | — | — |
Habitat Comparison
Ferruginous Duck
Freshwater lakes, marshes, and river deltas with dense emergent vegetation in southern Eurasia from central Europe east to Central Asia and China. Winters in the Mediterranean, South Asia, and sub-Saharan Africa.
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
Ferruginous Duck
Male emits a soft, wheeling purr; female gives a harsh, rapid quacking series. The male's quiet purring display call contrasts with the female's repeated, grating notes on Mediterranean marshes.
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
Ferruginous Duck
Breeds in boreal and sub-Arctic Canada; winters on the Atlantic coast from New England to the Gulf States.
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
保全状況
Ferruginous Duck
Brent Goose
How to Tell Them Apart
Ferruginous Duck
Rich chestnut-brown head, neck and breast; white undertail conspicuous. White eye in males (brown in females). Dark back. Bold white wing stripe in flight. Compact and rounded. Males brighter chestnut; …
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
Ferruginous Duck
メジロガモはユーラシア中部に繁殖し、地中海地方や南アジアで越冬する潜水性カモです。雄は栗色の頭部と白い目が特徴的で、飛翔時に翼の白い帯が目立ちます。葦原や水草が豊富な湿地に生息し、絶滅危惧種に指定されています。
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。