Arctic Tern vs Mallard
Sterna paradisaea 比較対象 Anas platyrhynchos
Side-by-Side Comparison
| 属性 | Arctic Tern | Mallard |
|---|---|---|
| 学名 | Sterna paradisaea | Anas platyrhynchos |
| 目 | Charadriiformes | Anseriformes |
| 科 | Laridae | Anatidae |
| 保全状況 | Least Concern | Least Concern |
| 体長 | 34.0 cm (13.4 in) | 58.0 cm (22.8 in) |
| 翼開長 | 80.0 cm (31.5 in) | 90.0 cm (35.4 in) |
| 体重 | 110.0 g (3.88 oz) | 1100.0 g (38.80 oz) |
| 食性 | Small fish and crustaceans caught by plunge-diving from the air. Hovers briefly before diving. | Omnivorous — aquatic plants, seeds, insects, crustaceans, and mollusks. Feeds by dabbling, upending, and grazing … |
| 一腹卵数 | 2-3 | 4-18 |
| Population Trend | — | — |
Size Comparison
Habitat Comparison
Arctic Tern
Breeds on coastal and tundra habitats. Spends most of its life at sea over the open ocean. Nests in colonies on beaches and rocky shores.
Mallard
Nearly any wetland habitat including lakes, rivers, ponds, marshes, estuaries, and urban park ponds.
Song & Call Comparison
Arctic Tern
A sharp, grating 'kree-yah' alarm call. Also gives 'kik-kik-kik' near the nest. Highly aggressive vocally during the Arctic breeding season. Calls are harsh and insistent.
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
Arctic Tern
Breeds in the Arctic and sub-Arctic. Migrates to the Antarctic, experiencing two summers per year. Found on every ocean.
Mallard
Native across the Northern Hemisphere in North America, Europe, and Asia. Introduced to Australia and New Zealand.
保全状況
Arctic Tern
Mallard
How to Tell Them Apart
Arctic Tern
Pale grey upperparts, white underparts with a black cap. Blood-red bill and short red legs. Deeply forked tail streamers. Winter adults lose the full black cap.
Slender, pointed, bright red bill
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
Arctic Tern
キョクアジサシはあらゆる動物の中で最長の渡りを行い、毎年北極と南極を往復する約7万kmの旅をする。30年の寿命の中に、月への往復3回分に相当する飛翔距離を積み重ねる可能性がある。地球上でどの生物よりも多くの昼光を経験するこの驚異的な鳥は、太陽を追い続ける。
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。