Brent Goose vs Blue-winged Goose
Branta bernicla 比較対象 Cyanochen cyanoptera
Side-by-Side Comparison
| 属性 | Brent Goose | Blue-winged Goose |
|---|---|---|
| 学名 | Branta bernicla | Cyanochen cyanoptera |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Least Concern | Near Threatened |
| 体長 | — | — |
| 翼開長 | 63.9 cm (25.2 in) | 65.2 cm (25.7 in) |
| 体重 | 1335.0 g (47.09 oz) | 1796.25 g (63.36 oz) |
| 食性 | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … | Eats aquatic plants, seeds, and invertebrates; dabbles in shallow ponds; diet shifts toward invertebrates in … |
| 一腹卵数 | 1-10 | 4-12 |
| 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.
Blue-winged Goose
Alpine and subalpine grasslands, riverbanks, and marshy meadows at 2,800–4,200 m on the Ethiopian Highlands. Grazes along stream and river margins. Strongly tied to highland wetlands near cold mountain streams.
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.
Blue-winged Goose
A soft, nasal bleating call from Ethiopian highland wetlands. The NT status and restricted Afroalpine range mean vocalizations are poorly documented in systematic detail.
Geographic Range & Migration
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
Blue-winged Goose
Breeds in northern prairie wetlands; winters along the Atlantic and Gulf coasts of the United States.
保全状況
Brent Goose
Blue-winged Goose
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.
Blue-winged Goose
Mostly dull gray-brown; head paler gray. Distinctive pale blue wing patch conspicuous in flight. Underparts slightly paler. Bill and legs pinkish-gray. Sexes similar. Endemic to Ethiopian highlands.
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。
Blue-winged Goose
ブルーウィングドグースはエチオピア高地に固有の珍しいガン科鳥類です。青灰色の翼と栗色の体が特徴的です。高地の草原、渓流沿い、農地に生息し、草や農作物を採食します。エチオピアの高地にのみ生息する固有種で、保全状態は脆弱です。