American Black Duck vs Gadwall
Anas rubripes so với Mareca strepera
Side-by-Side Comparison
| Thuộc Tính | American Black Duck | Gadwall |
|---|---|---|
| Tên Khoa Học | Anas rubripes | Mareca strepera |
| Bộ | Anseriformes | Anseriformes |
| Họ | Anatidae | Anatidae |
| Tình Trạng Bảo Tồn | Least Concern | Least Concern |
| Chiều Dài | — | — |
| Chiều Dài Sải Cánh | 53,4 cm (21.0 in) | 50,3 cm (19.8 in) |
| Khối Lượng | 1211,25 g (42.73 oz) | 857,5 g (30.25 oz) |
| Chế Độ Ăn | Eats fish and aquatic invertebrates; dives in coastal and freshwater habitats; diet shifts toward molluscs … | Dabbles for seeds and aquatic invertebrates; diet shifts toward invertebrates in spring; forages in shallow … |
| Số Trứng | 1-17 | 5-15 |
| Population Trend | — | — |
Habitat Comparison
Môi Trường Sống Chung
American Black Duck only
Gadwall only
American Black Duck
Freshwater and brackish wetlands in eastern North America from Atlantic Canada south along the coast to Georgia. Breeds in northern bogs and wetlands. Winters on coastal marshes, estuaries, and freshwater lakes.
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
American Black Duck
Female produces a loud, deep quacking series; male gives a low, raspy grunt. Voice is deeper and huskier than a Mallard; pairs call powerfully across northeastern North American wetlands.
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
American Black Duck
Breeds in the steppe zone of Central Asia; winters in South Asia, East Africa, and coastal Southeast Asia.
Gadwall
Found year-round in Australia and New Zealand; nomadic in arid Australia, following temporary rainfall-fed wetlands.
Tình Trạng Bảo Tồn
American Black Duck
Gadwall
How to Tell Them Apart
American Black Duck
Sooty dark brown body; head and neck paler buff with dark streaking. Iridescent purple speculum without white border. Males have yellow-green bill; females olive with orange blotches. Silvery underwings in …
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
American Black Duck
A large dark brown dabbling duck closely resembling a very dark female Mallard, with purple speculum, yellowish-olive bill in males, and orange legs. Common in eastern North America. Hybridizes freely with Mallard; pure populations declining in the interior.
Gadwall
A medium-sized dabbling duck. Males appear grey-brown but are intricately patterned with fine grey vermiculations, black rump, and white speculum. Females resemble Mallard but with orange-sided bill. Widespread across Eurasia and North America. Feeds by dabbling and grazing.