Arctic Tern vs Blue Jay
Sterna paradisaea 比較対象 Cyanocitta cristata
Side-by-Side Comparison
| 属性 | Arctic Tern | Blue Jay |
|---|---|---|
| 学名 | Sterna paradisaea | Cyanocitta cristata |
| 目 | Charadriiformes | Passeriformes |
| 科 | Laridae | Corvidae |
| 保全状況 | Least Concern | Least Concern |
| 体長 | 34.0 cm (13.4 in) | 28.0 cm (11.0 in) |
| 翼開長 | 80.0 cm (31.5 in) | 42.0 cm (16.5 in) |
| 体重 | 110.0 g (3.88 oz) | 87.0 g (3.07 oz) |
| 食性 | Small fish and crustaceans caught by plunge-diving from the air. Hovers briefly before diving. | Omnivorous — nuts (especially acorns), seeds, berries, insects, and occasionally eggs or nestlings of other … |
| 一腹卵数 | 2-3 | 2-7 |
| 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.
Blue Jay
Deciduous and mixed forests, parks, and suburban areas. Highly adaptable to human-modified landscapes.
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.
Blue Jay
A harsh, ringing 'jaay-jaay-jaay'. Also mimics Red-tailed Hawk and other species convincingly. Gives soft, liquid 'bell' calls and gurgling whispers in flocks.
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.
Blue Jay
Eastern and central North America from southern Canada to the Gulf Coast. Some populations migrate irregularly.
保全状況
Arctic Tern
Blue Jay
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
Blue Jay
Bright blue upperparts with black barring on the wings and tail. White face and underparts with a black necklace. Prominent blue crest.
Stout, straight black bill
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。
Blue Jay
アオカケスは鮮やかな羽毛と大きな鳴き声で知られるカラス科の大胆で知能が高い鳥。アオカケスは毎秋数千個のドングリを蓄えることでカシの木の重要な散布者となっている。複雑な社会的行動には、給餌器から他の鳥を追い払うためにタカの声を真似ることも含まれる。