Brent Goose vs Gadwall
Branta bernicla 对比 Mareca strepera
Side-by-Side Comparison
| 属性 | Brent Goose | Gadwall |
|---|---|---|
| 学名 | Branta bernicla | Mareca strepera |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保护状况 | Least Concern | Least Concern |
| 体长 | — | — |
| 翼展 | 63.9 cm (25.2 in) | 50.3 cm (19.8 in) |
| 体重 | 1335.0 g (47.09 oz) | 857.5 g (30.25 oz) |
| 食性 | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … | Dabbles for seeds and aquatic invertebrates; diet shifts toward invertebrates in spring; forages in shallow … |
| 产卵数 | 1-10 | 5-15 |
| 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.
Gadwall
Freshwater lakes, reservoirs, marshes, and rivers with emergent vegetation across Eurasia and North America. Winters on large open wetlands and coastal estuaries. Range and population increasing in Europe.
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.
Gadwall
Male utters a soft, nasal nheck note; female produces a series of descending, quacking notes. Both sexes are relatively quiet; female's quacking is softer and less strident than a Mallard.
Geographic Range & Migration
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
Gadwall
Found year-round in Australia and New Zealand; nomadic in arid Australia, following temporary rainfall-fed wetlands.
保护状况
Brent Goose
Gadwall
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.
Gadwall
Males have finely vermiculated gray-brown plumage with black rump and undertail. White speculum patch diagnostic in flight. Females mottled brown like Mallard but smaller and with orange-sided bill. Subtle but …
About These Birds
Brent Goose
黑雁是小型海雁，繁殖于北极苔原，越冬于温带沿海地区。全身黑色，颈部有白色斑纹，腹部浅色或深色（因亚种而异）。以海草（大叶藻）和潮间带植物为食，高度依赖沿海湿地。在欧洲和北美分布有多个亚种，其中部分亚种数量因大叶藻减少而受到威胁。
Gadwall
赤膀鸭是北美和欧亚大陆广泛分布的水面鸭，雄鸟羽色低调，以其翼后缘的栗红色翼镜为特征，嘴黑色，腿橙色；雌鸟褐色。繁殖于北温带湖泊和沼泽，越冬于温带至亚热带地区。以水生植物为主食，偶尔取食无脊椎动物。