Wandering Whistling-duck vs Blue Duck
Dendrocygna arcuata compared with Hymenolaimus malacorhynchos
Side-by-Side Comparison
| Attribute | Wandering Whistling-duck | Blue Duck |
|---|---|---|
| Scientific Name | Dendrocygna arcuata | Hymenolaimus malacorhynchos |
| Order | Anseriformes | Anseriformes |
| Family | Anatidae | Anatidae |
| Conservation Status | Least Concern | Endangered |
| Length | — | — |
| Wingspan | 37.2 cm (14.6 in) | 45.6 cm (18.0 in) |
| Weight | 779.5 g (27.50 oz) | 861.75 g (30.40 oz) |
| Diet | Eats grasses, sedges, and aquatic plants in tundra; winter diet of coastal salt marsh grasses … | Eats aquatic invertebrates, seeds, and plant material; dabbles in shallow fresh water; invertebrate diet peaks … |
| Clutch Size | 6-15 | 5-6 |
| Population Trend | — | — |
Habitat Comparison
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.
Blue Duck
Fast-flowing clear turbulent mountain rivers and streams in pristine native forest at 300–1,500 m in both main islands of New Zealand. Requires undisturbed riparian habitat with abundant aquatic invertebrates.
Song & Call Comparison
Wandering Whistling-duck
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.
Blue Duck
A soft, musical whistle from fast-flowing South Island rivers. Call is a clear 'whio' — giving the bird its Maori name. Also gives a soft, reedy 'squeak'. Endangered; rarely heard.
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.
Blue Duck
Breeds on open prairie wetlands of the Great Plains; winters in shallow estuaries and marshes along the Gulf of Mexico.
Conservation Status
Wandering Whistling-duck
Blue Duck
How to Tell Them Apart
Wandering Whistling-duck
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.
Blue Duck
Distinctive slate-blue-gray plumage; breast spotted with chestnut-brown in both sexes. Pale bill with flexible pink lobes at tip. Chestnut eye. Sexes similar; adapted to fast-flowing mountain streams in New Zealand.
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.
Blue Duck
A medium-sized blue-grey torrent duck with a pale pink bill tipped with a distinctive flap of skin, and chestnut-spotted breast. Endemic to New Zealand's fast-flowing mountain rivers. One of New Zealand's most endangered endemics. Monogamous with strong site fidelity to individual river territories.