Amsterdam Duck vs Brent Goose
Anas marecula เปรียบเทียบกับ Branta bernicla
Side-by-Side Comparison
| คุณสมบัติ | Amsterdam Duck | Brent Goose |
|---|---|---|
| ชื่อวิทยาศาสตร์ | Anas marecula | Branta bernicla |
| อันดับ | Anseriformes | Anseriformes |
| วงศ์ตระกูล | Anatidae | Anatidae |
| สถานะการอนุรักษ์ | Extinct | Least Concern |
| ความยาว | — | — |
| กว้างปีก | — | 63.9 cm (25.2 in) |
| น้ำหนัก | 289.5 g (10.21 oz) | 1335.0 g (47.09 oz) |
| อาหาร | Extinct Auckland Islands Merganser; fed on freshwater fish and aquatic invertebrates in streams; inferred from … | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … |
| จำนวนไข่ | -- | 1-10 |
| Population Trend | — | — |
Habitat Comparison
Amsterdam Duck
Historically restricted to Amsterdam Island in the southern Indian Ocean. Now extinct. Presumably inhabited the island's freshwater sources and coastal areas.
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.
Song & Call Comparison
Amsterdam Duck
Extinct (EX). No recordings exist. As an Anas relative, likely gave a typical duck-like quacking call; male may have had a soft whistled note similar to other island teals.
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.
Geographic Range & Migration
Amsterdam Duck
Breeds on sub-Antarctic islands of the South Indian Ocean; disperses across the Southern Ocean when not nesting.
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
สถานะการอนุรักษ์
Amsterdam Duck
Brent Goose
How to Tell Them Apart
Amsterdam Duck
Extinct Amsterdam Island duck known only from bones and a single historical description. Presumably brown plumage typical of Anas dabbling ducks. Flightless or near-flightless; extirpated by introduced predators.
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.
About These Birds
Amsterdam Duck
An extinct diving duck known from subfossil remains discovered on Amsterdam Island in the southern Indian Ocean. Flightless or nearly flightless; probably resembled the Laysan Duck in size. Went extinct around 1800 following human colonization of the island.
Brent Goose
A small dark-bodied goose with a black head and neck, small white neck patches, and pale grey belly. Migrates between high-Arctic breeding grounds and temperate coastal wintering areas. Feeds on eel-grass and saltmarsh vegetation in winter. Three subspecies differ in belly coloration.