Hawaiian Duck vs Black-headed Duck
Anas wyvilliana comparé à Heteronetta atricapilla
Side-by-Side Comparison
| Attribut | Hawaiian Duck | Black-headed Duck |
|---|---|---|
| Nom scientifique | Anas wyvilliana | Heteronetta atricapilla |
| Ordre | Anseriformes | Anseriformes |
| Famille | Anatidae | Anatidae |
| Statut de conservation | Vulnerable | Least Concern |
| Longueur | — | — |
| Envergure | 44,0 cm (17.3 in) | 34,7 cm (13.7 in) |
| Poids | 573,25 g (20.22 oz) | 528,5 g (18.64 oz) |
| Régime alimentaire | Fish-diving duck of South American rivers; uses serrated bill to catch fish and aquatic invertebrates; … | Parasitic; adults may feed on aquatic plants, seeds, and invertebrates in South American marshes. Diet … |
| Taille de la couvée | 9-13 | 2 |
| Population Trend | — | — |
Habitat Comparison
Hawaiian Duck
Freshwater marshes, rivers, reservoirs, and taro fields on Kauai and other Hawaiian islands. Nests in dense vegetation near water. Threatened by hybridization with domestic or feral Mallards.
Song & Call Comparison
Hawaiian Duck
Female produces a raspy, descending quacking series; male gives a soft, nasal sound. Calls similar to Mallard but higher-pitched; alarm is a rapid-fire quacking rattle.
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 Duck
Ranges across sub-Saharan Africa in open grasslands and wetland edges. Locally nomadic following seasonal rainfall patterns.
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.
Statut de conservation
Hawaiian Duck
Black-headed Duck
How to Tell Them Apart
Hawaiian Duck
Mottled brown plumage; males may show slight green gloss on head but reduced compared to Mallard. Iridescent blue-purple speculum with white borders. Orange bill. Females similar to males; pale buff …
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 Duck
A medium-sized duck resembling a female Mallard, with mottled brown plumage and green speculum. Endemic to Hawaii; hybridizes with feral Mallards, threatening its genetic integrity. Found on freshwater wetlands of Kauai and other islands. Endangered; conservation focus on reducing hybridization.
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.