African Black Duck vs Emperor Goose
Anas sparsa 对比 Anser canagicus
Side-by-Side Comparison
| 属性 | African Black Duck | Emperor Goose |
|---|---|---|
| 学名 | Anas sparsa | Anser canagicus |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保护状况 | Least Concern | Least Concern |
| 体长 | — | — |
| 翼展 | 49.5 cm (19.5 in) | 74.8 cm (29.4 in) |
| 体重 | 996.8333333333334 g (35.16 oz) | 2300.45 g (81.15 oz) |
| 食性 | Eats molluscs, crustaceans, and aquatic invertebrates; dives in coastal and freshwater habitats; diet heavier in … | Grazes aquatic plants and terrestrial grasses; upends in shallow water; winter diet shifts toward grain … |
| 产卵数 | 4-9 | 1-8 |
| Population Trend | — | — |
Habitat Comparison
African Black Duck
Fast-flowing rocky rivers and streams, mountain gorges, and waterfalls from sea level to 4,000 m across sub-Saharan Africa from Ethiopia and Kenya south to the Cape. Requires clear turbulent water with boulders.
Emperor Goose
Breeds on coastal tundra near the Bering Sea in Alaska and Chukotka. Winters on rocky coastal shorelines, kelp beds, and intertidal flats along the Aleutian Islands and Alaska Peninsula.
Song & Call Comparison
African Black Duck
Produces a harsh, resonant quacking call; alarm is a loud, emphatic quack repeated rapidly. Both sexes call with strong quacking; pairs duet with synchronized calls along African rivers.
Emperor Goose
A low, nasal 'clag-clag' call. Less vocal than other Anser geese. Gives contact calls in flocks during Arctic breeding and Pacific coast wintering. Somewhat quiet.
Geographic Range & Migration
African Black Duck
Resident across South and Southeast Asia, from India to southern China and the Philippines. Non-migratory in most of its range.
Emperor Goose
Breeds in the eastern Arctic of Canada; winters along the Atlantic coast from Newfoundland to Florida and occasionally to Texas.
保护状况
African Black Duck
Emperor Goose
How to Tell Them Apart
African Black Duck
Dark blackish-brown plumage with bold white spots on back and scapulars. Iridescent blue-green speculum with white borders. Head dark with pale spots. Bill and legs dark gray. Sexes similar. Fast-flowing …
Emperor Goose
Body plumage blue-gray with black and white feather scalloping. White head and hindneck contrasting with dark throat. Orange-yellow legs. Bill pink-orange. Tail white. Adults striking; sexes similar.
About These Birds
African Black Duck
A medium-sized dark brown duck with white spots on the back, a dark bill, and orange legs. Found along fast-flowing rocky rivers and streams in Africa. Territorial and monogamous; pairs defend stretches of river. Related to Pacific Black Duck.
Emperor Goose
皇帝雁是一种中型海雁，繁殖于阿拉斯加西部及西伯利亚东北部，越冬于阿留申群岛沿岸。头部和颈背白色，颈前黑色，形成鲜明对比。主要栖息于海滨苔原和沿海滩涂，以草地植物和海藻为食。受栖息地变化和气候变暖的影响，种群数量已有所下降。