Brent Goose vs Green Pygmy-goose
Branta bernicla 比較対象 Nettapus pulchellus
Side-by-Side Comparison
| 属性 | Brent Goose | Green Pygmy-goose |
|---|---|---|
| 学名 | Branta bernicla | Nettapus pulchellus |
| 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) | 33.8 cm (13.3 in) |
| 体重 | 1335.0 g (47.09 oz) | 328.75 g (11.60 oz) |
| 食性 | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … | Eats seeds, aquatic plants, and invertebrates; dabbles in shallow fresh water; diet varies between seasons … |
| 一腹卵数 | 1-10 | 8-12 |
| 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.
Green Pygmy-goose
Lily-covered tropical freshwater billabongs, lagoons, and seasonal floodplains in New Guinea and the tropical Top End of the Northern Territory and Queensland, Australia. Highly dependent on aquatic vegetation.
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.
Green Pygmy-goose
Male gives a high-pitched, melodic two-note whistle; female produces a quiet, nasal grunt. Courtship includes rapid chattering exchanges between paired birds on tropical lagoons.
Geographic Range & Migration
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
Green Pygmy-goose
Breeds across northern and central Eurasia; winters in tropical Africa and South Asia.
保全状況
Brent Goose
Green Pygmy-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.
Green Pygmy-goose
Males have dark green head and neck with white cheek patch; dark back; white underparts; flanks gray-green with fine barring. Females duller with brown cap and white face. White wing …
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。
Green Pygmy-goose
グリーンピグミーグースはオーストラリア北部と東南アジアに分布する小型の木巣性カモです。雄は緑色の羽毛と白い斑点が美しいです。熱帯・亜熱帯の水草が豊富な湖、池、湿地に生息し、蓮の種子や水草を採食します。