Greater Scaup vs Brent Goose
Aythya marila 比較対象 Branta bernicla
Side-by-Side Comparison
| 属性 | Greater Scaup | Brent Goose |
|---|---|---|
| 学名 | Aythya marila | Branta bernicla |
| 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) | 63.9 cm (25.2 in) |
| 体重 | 984.0 g (34.71 oz) | 1335.0 g (47.09 oz) |
| 食性 | Eats molluscs, crustaceans, and aquatic invertebrates in coastal and freshwater habitats; diet shifts between invertebrate … | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … |
| 一腹卵数 | 4-12 | 1-10 |
| Population Trend | — | — |
Habitat Comparison
Greater Scaup
Breeds on tundra and boreal lakes in the Arctic and subarctic across Eurasia and North America. Winters in large numbers on coastal bays, estuaries, and large lakes in temperate regions.
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
Greater Scaup
Male gives a low, purring wheeze; female produces a harsh, rolling quacking sequence. Calls are very similar to Lesser Scaup but slightly lower-pitched; heard on open ocean bays in winter.
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
Greater Scaup
Breeds in the high Arctic of North America; winters offshore on the Atlantic coast from Labrador to South Carolina.
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
保全状況
Greater Scaup
Brent Goose
How to Tell Them Apart
Greater Scaup
Males have glossy green-black rounded head; white flanks and belly; black breast and undertail; gray back. Yellow eye. Bill blue-gray. Females dark brown with white face patch around bill. Longer …
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
Greater Scaup
北極圏で繁殖し、北半球の沿岸や大きな湖で越冬する潜水ガモ（体長42〜51cm）。雄は黒い頭胸部・灰色の体・白い脇が特徴。Aythya marila（スズガモ）は海の浅瀬で大きな群れを形成し、二枚貝を好む。日本の東京湾や瀬戸内海でも冬季に大群が観察される。Anatidae科。
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。