Brent Goose vs Crested Duck
Branta bernicla 比較対象 Lophonetta specularioides
Side-by-Side Comparison
| 属性 | Brent Goose | Crested Duck |
|---|---|---|
| 学名 | Branta bernicla | Lophonetta specularioides |
| 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) | 53.8 cm (21.2 in) |
| 体重 | 1335.0 g (47.09 oz) | 941.3833333333333 g (33.21 oz) |
| 食性 | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … | Feeds on seeds and aquatic invertebrates; dabbles in ponds and marshes; diet more invertebrate-heavy in … |
| 一腹卵数 | 1-10 | 5-8 |
| 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.
Crested Duck
Fast-flowing Andean rivers, lakes, and puna wetlands from sea level to 4,500 m in Peru, Bolivia, Chile, Argentina, and the Falkland Islands. Occupies both coastal and high-altitude wetland habitats.
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.
Crested Duck
Produces a harsh, rattling call and loud hissing alarm notes. Both sexes vocalize with grating, nasal croaking sounds echoing across Andean rocky shores and rivers.
Geographic Range & Migration
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
Crested Duck
Breeds across Eurasia; winters in sub-Saharan Africa. One of the most abundant Palearctic ducks on the African wintering grounds.
保全状況
Brent Goose
Crested 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.
Crested Duck
Brown body with dark streaking; long pointed crest on hindcrown. Face and throat pale with dark eye patch. Iridescent purple-bronze speculum bordered white. Bill and legs grayish. Sexes similar. Andean …
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。
Crested Duck
クレステッドダックは南米のアンデス山脈と南端のパタゴニアに分布するカモです。目の後ろの短い冠羽が特徴的です。高山の湖から南極近くの海岸まで幅広い環境に生息し、水草、藻類、無脊椎動物を採食します。