African Black Duck vs Common Eider
Anas sparsa compared with Somateria mollissima
Side-by-Side Comparison
| Attribute | African Black Duck | Common Eider |
|---|---|---|
| Scientific Name | Anas sparsa | Somateria mollissima |
| Order | Anseriformes | Anseriformes |
| Family | Anatidae | Anatidae |
| Conservation Status | Least Concern | Near Threatened |
| Length | — | — |
| Wingspan | 49.5 cm (19.5 in) | 56.0 cm (22.0 in) |
| Weight | 996.8333333333334 g (35.16 oz) | 2042.8333333333333 g (72.06 oz) |
| Diet | Eats molluscs, crustaceans, and aquatic invertebrates; dives in coastal and freshwater habitats; diet heavier in … | Dives for blue mussels, clams, and crustaceans in shallow coastal waters. Swallows shellfish whole and … |
| Clutch Size | 4-9 | 2-7 |
| Population Trend | — | — |
Habitat Comparison
African Black Duck
Fast-flowing rocky rivers and streams, mountain gorges, and waterfalls from sea level to 4,000 m across sub-Saharan Africa from Ethiopia and Kenya south to the Cape. Requires clear turbulent water with boulders.
Song & Call Comparison
African Black Duck
Produces a harsh, resonant quacking call; alarm is a loud, emphatic quack repeated rapidly. Both sexes call with strong quacking; pairs duet with synchronized calls along African rivers.
Common Eider
Male produces a loud, resonant ah-WOOO cooing; female gives a deep, guttural quacking series. The male's iconic moaning call echoes across North Atlantic coastlines; a classic seaduck sound.
Geographic Range & Migration
African Black Duck
Resident across South and Southeast Asia, from India to southern China and the Philippines. Non-migratory in most of its range.
Common Eider
Breeds on Arctic and subarctic coasts from the North Atlantic to the Pacific. Winters along coasts of northwestern Europe and eastern North America.
Conservation Status
African Black Duck
Common Eider
How to Tell Them Apart
African Black Duck
Dark blackish-brown plumage with bold white spots on back and scapulars. Iridescent blue-green speculum with white borders. Head dark with pale spots. Bill and legs dark gray. Sexes similar. Fast-flowing …
Common Eider
Male is strikingly pied: white back, neck, and breast contrasting with black cap, belly, and flanks; nape washed pale lime-green. Female uniformly barred warm tawny-brown with darker streaks.
About These Birds
African Black Duck
A medium-sized dark brown duck with white spots on the back, a dark bill, and orange legs. Found along fast-flowing rocky rivers and streams in Africa. Territorial and monogamous; pairs defend stretches of river. Related to Pacific Black Duck.
Common Eider
The heaviest duck in the Northern Hemisphere (~2 kg), family Anatidae. Breeds colonially on rocky coasts and islands of the North Atlantic and Arctic. Dives for mussels and crustaceans in shallow marine waters. Females line nests with insulating down. Near Threatened due to recent declines in parts of its range from hunting and pollution.