African Black Duck vs Knob-billed Duck
Anas sparsa 对比 Sarkidiornis melanotos
Side-by-Side Comparison
| 属性 | African Black Duck | Knob-billed Duck |
|---|---|---|
| 学名 | Anas sparsa | Sarkidiornis melanotos |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保护状况 | Least Concern | Least Concern |
| 体长 | — | — |
| 翼展 | 49.5 cm (19.5 in) | 64.2 cm (25.3 in) |
| 体重 | 996.8333333333334 g (35.16 oz) | 1817.5 g (64.11 oz) |
| 食性 | Eats molluscs, crustaceans, and aquatic invertebrates; dives in coastal and freshwater habitats; diet heavier in … | Dabbles for seeds and aquatic invertebrates; diet shifts toward invertebrate prey in spring breeding season; … |
| 产卵数 | 4-9 | 6-20 |
| 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.
Knob-billed Duck
Freshwater lakes, marshes, floodplains, and forested wetlands across sub-Saharan Africa and South and Southeast Asia from India to southern China. Nests in large tree hollows near water.
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.
Knob-billed Duck
A low, grunting 'wuk' or soft, nasal 'krank'. Similar to Comb Duck in call quality. Generally quiet; calls are not loud or distinctive compared to other large African waterfowl.
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.
Knob-billed Duck
Breeds on sub-Arctic tundra; winters on the Atlantic coast of North America from Labrador to Florida and the Gulf Coast.
保护状况
African Black Duck
Knob-billed Duck
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 …
Knob-billed Duck
Males have white head with black spots; iridescent dark blue-black back and wings; white underparts with gray flanks. Large black fleshy knob atop bill. Females smaller, brown, and lack the …
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.
Knob-billed Duck
Old World equivalent of the Comb Duck, with iridescent black-and-white body and the male's distinctive bill knob. Found across sub-Saharan Africa and South Asia. Uses tree cavities for nesting. Gregarious outside breeding season; forms large flocks at seasonal wetlands.