Laysan Duck vs Greater White-fronted Goose
Anas laysanensis 比較対象 Anser albifrons
Side-by-Side Comparison
| 属性 | Laysan Duck | Greater White-fronted Goose |
|---|---|---|
| 学名 | Anas laysanensis | Anser albifrons |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Critically Endangered | Least Concern |
| 体長 | — | — |
| 翼開長 | 39.7 cm (15.6 in) | 81.6 cm (32.1 in) |
| 体重 | 465.25 g (16.41 oz) | 2471.0 g (87.16 oz) |
| 食性 | -- | Dabbles for aquatic invertebrates, seeds, and plant material; diet shifts heavily toward invertebrates in breeding … |
| 一腹卵数 | 9-13 | 3-9 |
| Population Trend | — | — |
Habitat Comparison
Laysan Duck
Restricted to Laysan Island and Midway Atoll in the Hawaiian Islands. Inhabits the central hypersaline lagoon and surrounding vegetation. Feeds on brine shrimp and flies around the lagoon margin.
Greater White-fronted Goose
Breeds on Arctic and subarctic tundra and peatlands. Winters on estuaries, agricultural fields, freshwater marshes, and flooded meadows across Europe, Asia, and North America. One of the most widespread geese.
Song & Call Comparison
Laysan Duck
Female gives a soft, muffled quacking series; male utters a quiet rasp. Extremely rare; the soft, unobtrusive quacking calls are seldom heard on the remote Laysan Island lagoon.
Greater White-fronted Goose
A loud, laughing 'kow-lyuk' or musical 'wah-wah'. Gives a distinctive high-pitched yodeling quality lacking in Greylag. Highly vocal in large winter flocks.
Geographic Range & Migration
Laysan Duck
Greater White-fronted Goose
Breeds in the potholes region of the northern Great Plains; winters in the southern United States and along the Gulf Coast.
保全状況
Laysan Duck
Greater White-fronted Goose
How to Tell Them Apart
Laysan Duck
Brown plumage mottled and streaked buff and dark brown. White eye-ring contrasts with dark face. Both sexes similar; females show reduced white eye ring. Iridescent speculum. Critically endangered; only on …
Greater White-fronted Goose
Brown-gray body with white forehead patch bordered by white band at bill base. Underparts with bold irregular black bars on belly. Orange bill; orange-yellow legs. Juveniles lack white front and …
About These Birds
Laysan Duck
レイサンガモはハワイのレイサン島にのみ生息する極めて希少な固有種です。マガモから進化したと考えられており、翼に白い斑点があるのが特徴です。かつて絶滅の危機に瀕していましたが、保全活動により個体数が回復しています。飛翔能力は持ちますが、主に地上を歩いて採食します。
Greater White-fronted Goose
北極圏で繁殖し、温帯で越冬する大型のガン（体長64〜81cm）。成鳥は白い額と黒い腹部の横縞が特徴。Anser albifrons（マガン）は東アジア、ヨーロッパ、北米の広大な農地や湿地で越冬する。日本では宮城県伊豆沼などが重要な越冬地で、数万羽が集まる壮観な光景が見られる。Anatidae科。