Brent Goose vs Black-bellied Whistling-duck
Branta bernicla 比較対象 Dendrocygna autumnalis
Side-by-Side Comparison
| 属性 | Brent Goose | Black-bellied Whistling-duck |
|---|---|---|
| 学名 | Branta bernicla | Dendrocygna autumnalis |
| 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) | 48.2 cm (19.0 in) |
| 体重 | 1335.0 g (47.09 oz) | 757.9 g (26.73 oz) |
| 食性 | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … | Grazes subarctic tundra grasses and sedges; winters on coastal salt marshes and agricultural fields eating … |
| 一腹卵数 | 1-10 | 9-18 |
| 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.
Black-bellied Whistling-duck
Freshwater wetlands, ponds, lake margins, flooded fields, and wooded swamps from the southern United States and Mexico through Central America to Ecuador, Bolivia, and Argentina. Uses nest boxes readily.
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.
Black-bellied Whistling-duck
A high, reedy whistle 'pe-che-che-ne' given in flight. Flocks produce a continuous whistling chorus. Also gives a squeaky 'whe-eee' contact call while swimming.
Geographic Range & Migration
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
Black-bellied Whistling-duck
Inhabits freshwater marshes and riverbanks from southeastern Brazil to northern Argentina and Bolivia. Sedentary; locally common.
保全状況
Brent Goose
Black-bellied Whistling-duck
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.
Black-bellied Whistling-duck
Gray head with brown cap and chestnut breast; black belly is distinctive. Wings show broad white patch in flight. Coral-pink bill and long pink legs. Upright posture. 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。
Black-bellied Whistling-duck
ブラックベリードウィスリングダックは北中米から南米北部に分布するツリーダックです。赤い嘴と飛翔時の大きな白い翼斑が目立ちます。湿地、池、稲田、木の茂った水辺に生息し、草の種子を主に採食します。