Laysan Duck vs Mallard
Anas laysanensis 比較対象 Anas platyrhynchos
Side-by-Side Comparison
| 属性 | Laysan Duck | Mallard |
|---|---|---|
| 学名 | Anas laysanensis | Anas platyrhynchos |
| 目 | Anseriformes | Anseriformes |
| 科 | Anatidae | Anatidae |
| 保全状況 | Critically Endangered | Least Concern |
| 体長 | — | 58.0 cm (22.8 in) |
| 翼開長 | 39.7 cm (15.6 in) | 90.0 cm (35.4 in) |
| 体重 | 465.25 g (16.41 oz) | 1100.0 g (38.80 oz) |
| 食性 | Dives for small fish, aquatic invertebrates, and amphibians; serrated bill grips prey; diet fish-heavy in … | Omnivorous — aquatic plants, seeds, insects, crustaceans, and mollusks. Feeds by dabbling, upending, and grazing … |
| 一腹卵数 | 9-13 | 4-18 |
| Population Trend | — | — |
Size Comparison
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.
Mallard
Nearly any wetland habitat including lakes, rivers, ponds, marshes, estuaries, and urban park ponds.
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.
Mallard
Female gives the classic 'quack-quack-quack', descending in pitch. Male utters soft nasal 'raeb-raeb'. Both give a high 'gag-gag-gag' when alarmed or taking flight.
Geographic Range & Migration
Laysan Duck
Resident in West Africa from Senegal to Nigeria; inhabits rainforest streams and swamps. Sedentary and locally common.
Mallard
Native across the Northern Hemisphere in North America, Europe, and Asia. Introduced to Australia and New Zealand.
保全状況
Laysan Duck
Mallard
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 …
Mallard
Breeding males have an iridescent green head, white neck ring, chestnut breast, and grey body. Females are mottled brown. Both sexes show a blue speculum bordered by white.
Broad, flat bill — yellow-green in males, orange-brown in females
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。
Mallard
世界で最も一般的なカモ。雄は光沢のある緑色の頭、白い首輪、栗色の胸が特徴。体長50〜65cm。ほぼ世界中の湖、川、池、湿地に生息。雑食性で植物や無脊椎動物を食べる。多くの家禽カモの祖先。低危険種。