Spotted Whistling-duck vs Knob-billed Duck
Dendrocygna guttata compared with Sarkidiornis melanotos
Side-by-Side Comparison
| Attribute | Spotted Whistling-duck | Knob-billed Duck |
|---|---|---|
| Scientific Name | Dendrocygna guttata | Sarkidiornis melanotos |
| Order | Anseriformes | Anseriformes |
| Family | Anatidae | Anatidae |
| Conservation Status | Least Concern | Least Concern |
| Length | — | — |
| Wingspan | 41.3 cm (16.3 in) | 64.2 cm (25.3 in) |
| Weight | 677.5 g (23.90 oz) | 1817.5 g (64.11 oz) |
| Diet | Primarily herbivorous; grazes tundra grasses and sedges; winters on coastal marshes and farmland, switching to … | Dabbles for seeds and aquatic invertebrates; diet shifts toward invertebrate prey in spring breeding season; … |
| Clutch Size | 10-11 | 6-20 |
| Population Trend | — | — |
Habitat Comparison
Shared Habitats
Spotted Whistling-duck only
Knob-billed Duck only
None
Spotted Whistling-duck
Freshwater wetlands, rice fields, streams, and forest pools in New Guinea, Sulawesi, the Philippines, and Moluccas. Often found near forested rivers and seasonal swamps at low elevations.
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
Spotted Whistling-duck
A musical, high whistle similar to other whistling-ducks. Call is softer and less far-carrying than White-faced or Black-bellied species. Given in flight and on water.
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
Spotted Whistling-duck
Ranges widely across sub-Saharan Africa in open woodland and savanna. Largely sedentary with local seasonal movements to water.
Knob-billed Duck
Breeds on sub-Arctic tundra; winters on the Atlantic coast of North America from Labrador to Florida and the Gulf Coast.
Conservation Status
Spotted Whistling-duck
Knob-billed Duck
How to Tell Them Apart
Spotted Whistling-duck
Dark brown above; head and neck dark brown. Underparts heavily spotted white on dark brown ground, giving spotted appearance. Flanks with bold white spots. Pink-red bill and legs. Sexes similar.
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
Spotted Whistling-duck
A small dark brown whistling-duck with bold white spots on its flanks, orange-red bill and legs, and a pale face. Found in tropical wetlands of New Guinea, the Philippines, and Indonesia. Often found near freshwater streams and flooded grassland. Less gregarious than other whistling-ducks.
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.