African Black Duck vs Spectacled Eider
Anas sparsa в сравнении с Somateria fischeri
Side-by-Side Comparison
| Характеристика | African Black Duck | Spectacled Eider |
|---|---|---|
| Научное название | Anas sparsa | Somateria fischeri |
| Отряд | Anseriformes | Anseriformes |
| Семейство | Anatidae | Anatidae |
| Охранный статус | Least Concern | Near Threatened |
| Длина | — | — |
| Размах крыльев | 49,5 cm (19.5 in) | 49,2 cm (19.4 in) |
| Масса | 996,8333333333334 g (35.16 oz) | 1443,75 g (50.93 oz) |
| Питание | Eats molluscs, crustaceans, and aquatic invertebrates; dives in coastal and freshwater habitats; diet heavier in … | Dives for bivalves, crustaceans, and aquatic insects in shallow Arctic coastal and freshwater habitats. Insects … |
| Размер кладки | 4-9 | 1-9 |
| 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.
Spectacled Eider
Male gives a low, melodious aah-ooo cooing; female produces a guttural, grunting call. The male's ghostly, organ-like cooing call carries across Arctic tundra ponds in the breeding season.
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.
Spectacled Eider
Breeds on coastal tundra of western and northern Alaska. Winters along the Bering Sea coast from Alaska to Kamchatka. Largely sedentary.
Охранный статус
African Black Duck
Spectacled 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 …
Spectacled Eider
Male has white back and black breast with pale sage-green head framed by large white goggle-like spectacles edged black. Female mottled tawny-brown with faint spectacle outline.
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.
Spectacled Eider
A medium-large sea duck of the family Anatidae, weighing ~1.4 kg with distinctive pale green goggles in males. Breeds on Arctic tundra of Alaska and Russia; winters in pack ice of the Bering Sea. Dives for benthic invertebrates and mollusks. Near Threatened due to population declines linked to lead poisoning and habitat change.