Brent Goose vs Lesser Whistling-duck
Branta bernicla 比較対象 Dendrocygna javanica
Side-by-Side Comparison
| 属性 | Brent Goose | Lesser Whistling-duck |
|---|---|---|
| 学名 | Branta bernicla | Dendrocygna javanica |
| 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) | 38.8 cm (15.3 in) |
| 体重 | 1335.0 g (47.09 oz) | 525.0 g (18.52 oz) |
| 食性 | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … | Grazes subarctic grasses and rushes; migratory; winters on estuarine mudflats and coastal grasslands eating eelgrass … |
| 一腹卵数 | 1-10 | 7-17 |
| 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.
Lesser Whistling-duck
Freshwater wetlands, lakes, rice paddies, mangroves, and slow rivers across South and Southeast Asia from India through southern China to Borneo and Indonesia. Common near cultivated land and human settlements.
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.
Lesser Whistling-duck
A softer, higher-pitched whistle than other Dendrocygna. Call is a quick 'we-we' given in flight. Smaller size reflected in higher-pitched and thinner quality of call.
Geographic Range & Migration
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
Lesser Whistling-duck
Breeds on tundra of northern Canada and Alaska; winters on the Pacific coast from California to Mexico and Central America.
保全状況
Brent Goose
Lesser 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.
Lesser Whistling-duck
Warm chestnut-brown overall; head and neck brown; upperparts dark brown. Chestnut rump and upper-tail conspicuous in flight. Flanks chestnut with pale streaks. Bill and legs dark gray. 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。
Lesser Whistling-duck
レッサーウィスリングダックは南アジアから東南アジアにかけて分布するツリーダックです。褐色の羽毛と特徴的な鳴き声を持ちます。稲田、湿地、マングローブ林に生息し、水草の種子や葉を採食します。アジアで最もよく見られるツリーダックです。