Mexican Duck vs Brent Goose
Anas diazi 比較対象 Branta bernicla
Side-by-Side Comparison
| 属性 | Mexican Duck | Brent Goose |
|---|---|---|
| 学名 | Anas diazi | Branta bernicla |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Not Evaluated | Least Concern |
| 体長 | — | — |
| 翼開長 | — | 63.9 cm (25.2 in) |
| 体重 | 1003.75 g (35.41 oz) | 1335.0 g (47.09 oz) |
| 食性 | Eats fish, molluscs, and aquatic invertebrates; dives in fresh and salt water; diet shifts between … | Primarily herbivorous; grazes aquatic plants, grasses, and sedges; swans upend in shallow water for submerged … |
| 一腹卵数 | 1-13 | 1-10 |
| Population Trend | — | — |
Habitat Comparison
Mexican Duck
Freshwater lakes, marshes, and rivers at 1,000–2,500 m in the highlands of Mexico and the southwestern United States. Uses agricultural ponds and irrigation canals.
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
Mexican Duck
Female gives a Mallard-like, descending quacking series; male utters a soft, nasal grunt. Vocalizations essentially identical to Mallard; found in Mexican interior wetlands and the Rio Grande.
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
Mexican Duck
Breeds in central and eastern Siberia; winters in East Asia, Southeast Asia, and the East African coast.
Brent Goose
Breeds across boreal and subarctic Canada and Alaska; winters in the southern United States, Mexico, and Central America.
保全状況
Mexican Duck
Brent Goose
How to Tell Them Apart
Mexican Duck
Similar to Mottled Duck; mottled brown plumage with pale buff head showing dark crown and eye stripe. Iridescent blue-purple speculum with white borders. Yellow-orange bill. Both sexes similar. SW USA …
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
Mexican Duck
メキシコガモとも呼ばれるこの種は、メキシコ中央高原および米国南西部の湿地や河川に生息する中型のカモです。褐色の羽毛と緑色の嘴が特徴で、マガモと近縁ですが、独立した種として扱われています。生息地の破壊と狩猟圧力により個体数が減少しており、保全が求められています。
Brent Goose
北極圏で繁殖し、北半球の海岸で越冬する小型のガン（体長55〜66cm）。黒い頭・首・胸に短い白い首輪が特徴。Branta bernicla（コクガン）は主にアマモなどの海草を食べ、干潟や浅い入り江を好む。日本でも北海道・東北の海岸で越冬する姿が見られ、個体数は比較的少ない。Anatidae科。