Hawaiian Goose vs Black-headed Duck
Branta sandvicensis compared with Heteronetta atricapilla
Side-by-Side Comparison
| Attribute | Hawaiian Goose | Black-headed Duck |
|---|---|---|
| Scientific Name | Branta sandvicensis | Heteronetta atricapilla |
| Order | Anseriformes | Anseriformes |
| Family | Anatidae | Anatidae |
| Conservation Status | Near Threatened | Least Concern |
| Length | — | — |
| Wingspan | 72.8 cm (28.7 in) | 34.7 cm (13.7 in) |
| Weight | 2150.0 g (75.84 oz) | 528.5 g (18.64 oz) |
| Diet | Eats aquatic plants, algae, and grasses; upends in shallow water to graze submerged vegetation; diet … | Parasitic; adults may feed on aquatic plants, seeds, and invertebrates in South American marshes. Diet … |
| Clutch Size | 1-6 | 2 |
| Population Trend | — | — |
Habitat Comparison
Hawaiian Goose
Volcanic slopes, lava flows, coastal grasslands, and shrublands on Maui, Hawai'i, and Kauai. Adapted to rocky terrain with reduced toe webbing. Introduced to other Hawaiian islands. Avoids dense forest.
Song & Call Comparison
Hawaiian Goose
A soft, low 'moo-moo' — the murmuring call gives the Nene its Hawaiian name. Also gives honking calls in flight. Less vocal than Canada Goose; distinctive murmuring quality.
Black-headed Duck
Male gives a soft, raspy peeping note; female produces a muted quack. An obligate brood parasite with reduced vocalizations; subdued calls suit its secretive lifestyle among Argentine reeds.
Geographic Range & Migration
Hawaiian Goose
Breeds in sub-Arctic Canada; winters on large lakes and rivers from the Gulf of Mexico north to where water remains open.
Black-headed Duck
Resident in southern South America from southern Brazil and Bolivia south to Argentina and Chile. Found on lakes and marshes in open lowlands.
Conservation Status
Hawaiian Goose
Black-headed Duck
How to Tell Them Apart
Hawaiian Goose
Buff-tan neck with black and white channeled furrows. Crown and face black; hindneck black. Body gray-brown above; underparts pale with buff breast. Reduced webbing on feet. Sexes similar. State bird …
Black-headed Duck
Male has distinctive jet-black head and neck, warm chestnut-brown back, and pale buff underparts; blue-grey bill with red base. Female is streaked brown above with pale supercilium and whitish underparts.
About These Birds
Hawaiian Goose
Hawaii's state bird and the world's rarest goose, recovered from near extinction. A medium-sized brownish goose with a black face, pale buff neck with diagonal stripes, and reduced webbing between the toes adapted for walking on lava. Grazes on volcanic slopes and coastal areas.
Black-headed Duck
A small diving duck (~530 g) of South America, family Anatidae, and the sole member of genus Heteronetta. Inhabits freshwater marshes and lakes in Argentina, Bolivia, Brazil, Chile, and Uruguay. Unique among waterfowl as an obligate brood parasite, laying eggs in nests of coots and other waterbirds. Feeds on seeds and aquatic invertebrates. Least Concern.