American Black Duck vs Knob-billed Duck
Anas rubripes comparado con Sarkidiornis melanotos
Side-by-Side Comparison
| Atributo | American Black Duck | Knob-billed Duck |
|---|---|---|
| Nombre científico | Anas rubripes | Sarkidiornis melanotos |
| Orden | Anseriformes | Anseriformes |
| Familia | Anatidae | Anatidae |
| Estado de conservación | Least Concern | Least Concern |
| Longitud | — | — |
| Envergadura | 53,4 cm (21.0 in) | 64,2 cm (25.3 in) |
| Peso | 1211,25 g (42.73 oz) | 1817,5 g (64.11 oz) |
| Dieta | Eats fish and aquatic invertebrates; dives in coastal and freshwater habitats; diet shifts toward molluscs … | Dabbles for seeds and aquatic invertebrates; diet shifts toward invertebrate prey in spring breeding season; … |
| Tamaño de la puesta | 1-17 | 6-20 |
| Population Trend | — | — |
Habitat Comparison
Hábitats compartidos
American Black Duck only
Knob-billed Duck only
American Black Duck
Freshwater and brackish wetlands in eastern North America from Atlantic Canada south along the coast to Georgia. Breeds in northern bogs and wetlands. Winters on coastal marshes, estuaries, and freshwater lakes.
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
American Black Duck
Female produces a loud, deep quacking series; male gives a low, raspy grunt. Voice is deeper and huskier than a Mallard; pairs call powerfully across northeastern North American wetlands.
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
American Black Duck
Breeds in the steppe zone of Central Asia; winters in South Asia, East Africa, and coastal Southeast Asia.
Knob-billed Duck
Breeds on sub-Arctic tundra; winters on the Atlantic coast of North America from Labrador to Florida and the Gulf Coast.
Estado de conservación
American Black Duck
Knob-billed Duck
How to Tell Them Apart
American Black Duck
Sooty dark brown body; head and neck paler buff with dark streaking. Iridescent purple speculum without white border. Males have yellow-green bill; females olive with orange blotches. Silvery underwings in …
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
American Black Duck
El pato negro americano es un gran pato de color marrón muy oscuro con una cabeza más clara y un llamativo espéculo alar púrpura. Habita en humedales del este de Norteamérica y se está hibridando cada vez más con el pato de collar introducido en su rango, lo que representa una amenaza para su pureza genética. Prefiere marismas costeras, pantanos boscosos y lagos tranquilos.
Knob-billed Duck
El pato crestudo africano y asiático es un gran pato arbóreo de África subsahariana, Madagascar y el sur de Asia. Similar al pato crestudo del Nuevo Mundo, el macho tiene una llamativa protuberancia sobre el pico que se vuelve mayor en la época de cría. Es un ave de grandes llanuras inundadas, pantanos y zonas de selva con ríos y lagunas de agua tranquila.