Wood Duck vs Brent Goose
Aix sponsa 比較対象 Branta bernicla
Side-by-Side Comparison
| 属性 | Wood Duck | Brent Goose |
|---|---|---|
| 学名 | Aix sponsa | Branta bernicla |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Least Concern | Least Concern |
| 体長 | — | — |
| 翼開長 | 44.1 cm (17.4 in) | 63.9 cm (25.2 in) |
| 体重 | 691.75 g (24.40 oz) | 1335.0 g (47.09 oz) |
| 食性 | Dabbles for seeds and aquatic invertebrates; diet shifts between plant matter and invertebrates seasonally in … | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … |
| 一腹卵数 | 9-15 | 1-10 |
| Population Trend | — | — |
Habitat Comparison
Wood Duck
Wooded swamps, beaver ponds, forested river margins, and tree-lined lakes in eastern and western North America. Nests in tree cavities up to 15m high. Readily uses nest boxes. Winters on wooded freshwater wetlands.
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.
Song & Call Comparison
Wood Duck
Male gives a loud, rising 'jeeee' whistle; female gives a soft, nasal 'oo-eek'. One of North America's most beautiful ducks; its call matches its spectacular appearance.
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.
Geographic Range & Migration
Wood Duck
Breeds in Eurasia; winters across tropical and southern Africa, the Middle East, and South and Southeast Asia.
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
保全状況
Wood Duck
Brent Goose
How to Tell Them Apart
Wood Duck
Males iridescent green and purple-crested head with white throat patches and facial stripes. Chestnut breast, buffy flanks, dark back. Red eye and bill. Females gray-brown with white eye-ring teardrop. Spectacular …
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.
About These Birds
Wood Duck
北アメリカ東部に広く分布する美しいカモ（体長44〜54cm）。雄は金属光沢のある頭部と複雑な羽模様を持ち、Aix galericulataに次ぐ美麗種として知られる。Aix sponsa（キンクロハジロモドキ）は木の洞に巣を作る珍しいカモで、水辺の林を主な生息地とする。20世紀初頭には乱獲で激減したが、保護活動により回復。Anatidae科。
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。