Brent Goose vs Surf Scoter
Branta bernicla 比較対象 Melanitta perspicillata
Side-by-Side Comparison
| 属性 | Brent Goose | Surf Scoter |
|---|---|---|
| 学名 | Branta bernicla | Melanitta perspicillata |
| 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) | 45.3 cm (17.8 in) |
| 体重 | 1335.0 g (47.09 oz) | 1019.75 g (35.97 oz) |
| 食性 | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … | Dives for molluscs, crustaceans, and herring spawn in coastal waters. Uses its distinctive swollen bill … |
| 一腹卵数 | 1-10 | 5-9 |
| 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.
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.
Surf Scoter
Male produces a low, gurgling burble; female gives a crow-like, guttural cawing. The female's rasping, crow-like call is startling; males make soft, liquid gurgling notes during courtship.
Geographic Range & Migration
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
Surf Scoter
Breeds in boreal forests and tundra of northern North America. Winters along Pacific and Atlantic coasts south to Baja California and the Carolinas.
保全状況
Brent Goose
Surf Scoter
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.
Surf Scoter
Male is entirely glossy black except for white patches on forehead and nape; bill tricolored orange, red, and white with black spot. Female sooty-brown with two white facial patches.
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。
Surf Scoter
サーフスコーター。北米固有の海ガモ。雄は黒色の体に白い後頭部と前額の白斑が特徴的で、多彩な色の嘴も目立つ。北米のタイガ湖で繁殖し、冬は太平洋・大西洋沿岸に移動。貝類を主食とする。低危険種。