Brent Goose vs Orinoco Goose
Branta bernicla 比較対象 Neochen jubata
Side-by-Side Comparison
| 属性 | Brent Goose | Orinoco Goose |
|---|---|---|
| 学名 | Branta bernicla | Neochen jubata |
| 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) | 59.6 cm (23.5 in) |
| 体重 | 1335.0 g (47.09 oz) | 1558.0 g (54.96 oz) |
| 食性 | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … | Eats grasses, seeds, and aquatic invertebrates; grazes wetland margins; takes molluscs and crustaceans in shallow … |
| 一腹卵数 | 1-10 | 6-10 |
| 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.
Orinoco Goose
Tropical rivers, river islands, sandy beaches, and adjacent gallery forest in the Amazon and Orinoco basins. Nests in tree cavities or on the ground near rivers. Associated with braided river channels.
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.
Orinoco Goose
A nasal 'honk-honk' call. Less frequently encountered than other South American waterfowl; calls from gallery forest beside major Orinoco tributaries during the breeding season.
Geographic Range & Migration
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
Orinoco Goose
Bred on Amsterdam Island and possibly other sub-Antarctic islets. Extinct; flightless and confined to one small island.
保全状況
Brent Goose
Orinoco 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.
Orinoco Goose
Pale cream-buff head and neck; chestnut-brown breast and flanks. Back dark brown; belly pale cream. Wings with iridescent green speculum and white inner secondaries. Bill dark; legs reddish-orange. Sexes similar.
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。
Orinoco Goose
A pale-headed chestnut-and-white goose-like bird with a narrow dark mane on the neck. Found on tropical river islands and forest-edge wetlands of the Amazon and Orinoco basins. Perches prominently in trees. Monogamous with strong territorial behavior.