Brent Goose vs Freckled Duck
Branta bernicla 比較対象 Stictonetta naevosa
Side-by-Side Comparison
| 属性 | Brent Goose | Freckled Duck |
|---|---|---|
| 学名 | Branta bernicla | Stictonetta naevosa |
| 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) | 46.5 cm (18.3 in) |
| 体重 | 1335.0 g (47.09 oz) | 888.25 g (31.33 oz) |
| 食性 | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … | Filter-feeds on invertebrates and seeds in shallow water; upends in wetlands; diet shifts toward plant … |
| 一腹卵数 | 1-10 | 5-10 |
| 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.
Freckled Duck
Dense inland freshwater swamps, tea-tree bogs, and reedy lakes across southern and inland Australia. Highly nomadic; follows ephemeral inland flooding. Key breeding sites in Murray-Darling Basin swamps.
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.
Freckled Duck
Soft, nasal 'quacking' and grunting sounds. Considered a quieter, more secretive duck than most. Males give a soft wheeze; females give low quacks. Not vocal by duck standards.
Geographic Range & Migration
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
Freckled Duck
Breeds in the sub-Arctic and boreal regions of North America; winters inland and coastally across the southern United States.
保全状況
Brent Goose
Freckled 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.
Freckled Duck
Dark grayish-brown plumage densely freckled with pale spots and streaks throughout. Head large and rounded with peaked crown. Bill gray-blue with red patch at base in breeding males. 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。
Freckled Duck
フレックルドダックはオーストラリア南東部に固有の珍しいカモです。全身に細かい白い斑点がある褐色の羽毛が特徴です。深い水草に覆われた恒久的な湿地に生息し、主に水草や藻類を採食します。比較的稀な種で、オーストラリアの保全上重要な種です。