Wandering Whistling-duck vs Knob-billed Duck

Dendrocygna arcuata compared with Sarkidiornis melanotos

Side-by-Side Comparison

Attribute Wandering Whistling-duck Knob-billed Duck
Scientific Name Dendrocygna arcuata Sarkidiornis melanotos
Order Anseriformes Anseriformes
Family Anatidae Anatidae
Conservation Status Least Concern Least Concern
Length
Wingspan 37.2 cm (14.6 in) 64.2 cm (25.3 in)
Weight 779.5 g (27.50 oz) 1817.5 g (64.11 oz)
Diet Eats grasses, sedges, and aquatic plants in tundra; winter diet of coastal salt marsh grasses … --
Clutch Size 6-15 6-20
Population Trend

Habitat Comparison

Shared Habitats

Wandering Whistling-duck only

None

Knob-billed Duck only

Wandering Whistling-duck

Tropical freshwater marshes, flooded grasslands, swamps, and lake margins from the Philippines and Indonesia through Papua New Guinea to northern and eastern Australia. Nomadic following wet season flooding.

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

Wandering Whistling-duck

Song

A soft whistle 'whi-whi-whi' in flight. Less vocal than other whistling-ducks; flocks tend to be quieter. Given at dawn and dusk during flight to roosting or feeding areas.

Knob-billed Duck

Song

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

Wandering Whistling-duck

Breeds in Arctic and subarctic regions; winters at sea around the Antarctic pack ice, one of the longest migrations known.

Knob-billed Duck

Conservation Status

Least Concern

Wandering Whistling-duck

Least Concern

Knob-billed Duck

How to Tell Them Apart

Wandering Whistling-duck

Plumage

Rich chestnut-brown head and neck; dark brown back. Flanks rufous with pale buff streaks and dark spots. Belly blackish. Long, dark pinkish legs. Upright posture typical of whistling-ducks. Sexes similar.

Knob-billed Duck

Plumage

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

Wandering Whistling-duck

A medium-sized whistling-duck with rufous-brown body, dark brown back, pale buff underparts, and a chestnut collar. Found in tropical wetlands from Indonesia to Australia and Pacific islands. Highly social and nomadic. Forages by dabbling and diving in shallow freshwater.

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.

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