Brent Goose vs Steller's Eider
Branta bernicla comparado com Polysticta stelleri
Side-by-Side Comparison
| Atributo | Brent Goose | Steller's Eider |
|---|---|---|
| Nome científico | Branta bernicla | Polysticta stelleri |
| Ordem | Anseriformes | Anseriformes |
| Família | Anatidae | Anatidae |
| Estado de conservação | Least Concern | Vulnerable |
| Comprimento | — | — |
| Envergadura | 63,9 cm (25.2 in) | 40,7 cm (16.0 in) |
| Peso | 1335,0 g (47.09 oz) | 815,75 g (28.77 oz) |
| Dieta | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … | Eats molluscs, crustaceans, and aquatic invertebrates; dives in shallow coastal and estuarine habitats; diet invertebrate-dominated. |
| Tamanho da postura | 1-10 | 3-10 |
| Population Trend | — | — |
Habitat Comparison
Brent Goose
Breeds on high-Arctic tundra; winters on estuaries, coastal mudflats, saltmarshes, and sea-grass beds along Atlantic and Pacific coastlines. One of the most strictly coastal wintering geese.
Steller's Eider
Breeds on low-lying coastal tundra in Arctic Russia and occasionally Alaska. Winters on shallow rocky sea coasts, kelp beds, and sheltered bays in the Baltic Sea and Pacific coast of Alaska. Listed as Vulnerable.
Song & Call Comparison
Brent Goose
A low, guttural 'rronk' or 'ronk-ronk' from flocks. Soft nasal calls in feeding groups. A subtle, understated call for a goose — less loud than most Anser geese.
Steller's Eider
Male produces a low, soft cooing note; female gives a guttural, grunting purr. Quieter than other eiders; the male's gentle cooing is unlike the louder calls of the Common Eider.
Geographic Range & Migration
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
Steller's Eider
Breeds in boreal Canada and Alaska; winters along Pacific and Atlantic coasts and on large interior lakes of the US.
Estado de conservação
Brent Goose
Steller's Eider
How to Tell Them Apart
Brent Goose
Small; mostly black head, neck, and breast. Small white neck-patch on adults. Back dark brownish-gray; belly pale gray to white depending on subspecies. White undertail coverts. Sexes similar.
Steller's Eider
Males have white head with green nape spot, black eye patch and chin; orange-buff underparts; black back with white wing patches. Females mottled dark brown with blue speculum bordered white. …
About These Birds
Brent Goose
O ganso-ruivo é um pequeno ganso marinho que cria na tundra ártica e hiberna em costas marinhas temperadas. Tem cabeça e pescoço pretos com remendo branco manchado no pescoço. As subespécies variam nas cores do ventre de pálido a escuro. Alimenta-se de ervas marinhas, alfaces-do-mar e outras plantas costeiras. As populações colapsaram nos anos 1930 devido ao declínio das ervas marinhas, mas recuperaram com o retorno destas. Estão entre os gansos que percorrem as maiores distâncias de migração.
Steller's Eider
O êider-de-steller é o menor dos quatro patos êider, com plumagem elaborada e intrincada nos machos. Os machos têm cabeça branca com olhos verdes marcantes, nuca verde, peito laranja-avermelhado e pontos negros no peito. Cria em pântanos de tundra ártica na Rússia e Alaska. As populações do Alaska colapsaram dramaticamente, levando à sua listagem como ameaçada nos Estados Unidos. As causas do declínio ainda não são totalmente compreendidas.