Black-headed Duck vs Common Shelduck
Heteronetta atricapilla ile kıyaslandığında Tadorna tadorna
Side-by-Side Comparison
| Özellik | Black-headed Duck | Common Shelduck |
|---|---|---|
| Bilimsel Ad | Heteronetta atricapilla | Tadorna tadorna |
| Takım | Anseriformes | Anseriformes |
| Familya | Anatidae | Anatidae |
| Koruma Durumu | Least Concern | Least Concern |
| Uzunluk | — | — |
| Kanat Açıklığı | 34,7 cm (13.7 in) | 62,8 cm (24.7 in) |
| Ağırlık | 528,5 g (18.64 oz) | 1035,5 g (36.53 oz) |
| Beslenme | Parasitic; adults may feed on aquatic plants, seeds, and invertebrates in South American marshes. Diet … | Eats seeds, leaves, and aquatic invertebrates; dabbles in shallow water; diet broadly omnivorous and varies … |
| Kuluçka Büyüklüğü | 2 | 3-18 |
| Population Trend | — | — |
Habitat Comparison
Common Shelduck
Coastal estuaries, mudflats, saltmarshes, sand dunes, and inland saline lakes from northwest Europe east across Eurasia to China. Winters mainly on tidal estuaries and coastal wetlands. Nests in burrows.
Song & Call Comparison
Black-headed Duck
Male gives a soft, raspy peeping note; female produces a muted quack. An obligate brood parasite with reduced vocalizations; subdued calls suit its secretive lifestyle among Argentine reeds.
Common Shelduck
Male gives a whistled 'wheee'; female gives a cackling series of rapid nasal 'ak-ak-ak' notes. One of the most sexually dimorphic calls of any shelduck species.
Geographic Range & Migration
Black-headed Duck
Resident in southern South America from southern Brazil and Bolivia south to Argentina and Chile. Found on lakes and marshes in open lowlands.
Common Shelduck
Breeds in Siberian tundra; winters in eastern and southern Africa, and in South and Southeast Asia. Trans-hemispheric migrant.
Koruma Durumu
Black-headed Duck
Common Shelduck
How to Tell Them Apart
Black-headed Duck
Male has distinctive jet-black head and neck, warm chestnut-brown back, and pale buff underparts; blue-grey bill with red base. Female is streaked brown above with pale supercilium and whitish underparts.
Common Shelduck
White body with dark green head, broad chestnut breastband, and black scapular stripes. Red bill with basal knob in males. Green speculum and black wingtips. Underparts white with black belly …
About These Birds
Black-headed Duck
A small diving duck (~530 g) of South America, family Anatidae, and the sole member of genus Heteronetta. Inhabits freshwater marshes and lakes in Argentina, Bolivia, Brazil, Chile, and Uruguay. Unique among waterfowl as an obligate brood parasite, laying eggs in nests of coots and other waterbirds. Feeds on seeds and aquatic invertebrates. Least Concern.
Common Shelduck
A large distinctive shelduck with a white body, dark green head, broad chestnut breast band, and a bright red bill with a knob in males. Common along European and Asian coasts and estuaries. Nests in rabbit burrows or hollow trees. Large moult migrations concentrate in Germany's Wadden Sea.