Brent Goose vs Upland Goose
Branta bernicla 比較対象 Chloephaga picta
Side-by-Side Comparison
| 属性 | Brent Goose | Upland Goose |
|---|---|---|
| 学名 | Branta bernicla | Chloephaga picta |
| 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) | 82.4 cm (32.4 in) |
| 体重 | 1335.0 g (47.09 oz) | 2916.0 g (102.86 oz) |
| 食性 | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … | -- |
| 一腹卵数 | 1-10 | 5-8 |
| 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.
Upland Goose
Open Patagonian grasslands, steppe, and agricultural pastures in southern Chile and Argentina, including the Falkland Islands. Grazes on short grass. Males aggressively defend territories. Partially migratory.
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.
Upland Goose
Male gives a high, whistled 'whew'; female gives a low, rolling cackle 'ga-ga-ga'. Sexual differences in call are pronounced. Falklands and Patagonian populations highly vocal.
Geographic Range & Migration
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
Upland Goose
保全状況
Brent Goose
Upland 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.
Upland Goose
Pronounced dimorphism. Males white with black-barred flanks and white wings with black primaries. Females rufous-brown with black-barred flanks and white belly. Both sexes yellow-orange legs. Grassland species.
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。
Upland Goose
マゼランガンは南米南端のパタゴニアとフォークランド諸島に分布するガン科鳥類です。雄は白い頭部と黒白の羽毛、雌は褐色の羽毛が特徴的です。草地や農地に生息し、草を採食します。羊牧場主との競合で駆除されることがあります。