Arctic Tern vs Forster's Tern
Sterna paradisaea so với Sterna forsteri
Side-by-Side Comparison
| Thuộc Tính | Arctic Tern | Forster's Tern |
|---|---|---|
| Tên Khoa Học | Sterna paradisaea | Sterna forsteri |
| Bộ | Charadriiformes | Charadriiformes |
| Họ | Laridae | Laridae |
| Tình Trạng Bảo Tồn | Least Concern | Least Concern |
| Chiều Dài | 34,0 cm (13.4 in) | — |
| Chiều Dài Sải Cánh | 80,0 cm (31.5 in) | 50,5 cm (19.9 in) |
| Khối Lượng | 110,0 g (3.88 oz) | 151,25 g (5.34 oz) |
| Chế Độ Ăn | Small fish and crustaceans caught by plunge-diving from the air. Hovers briefly before diving. | -- |
| Số Trứng | 2-3 | 2-3 |
| 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.
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.
Forster's Tern
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.
Forster's Tern
Tình Trạng Bảo Tồn
Arctic Tern
Forster's Tern
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
Forster's Tern
About These Birds
Arctic Tern
The Arctic tern holds the record for the longest known migration of any animal, traveling roughly 70,000 km annually from Arctic to Antarctic and back. Over its 30-year lifespan, it may fly the equivalent of three round trips to the Moon. This remarkable bird experiences more daylight than any other creature on Earth.
Forster's Tern
Forster's Tern, 33–36 cm, breeds in interior North American marshes and winters along both US coasts and into Mexico. Distinctive frosted silver upperparts and orange-based bill. In non-breeding plumage, shows a black eye-mask. Piscivore; hovers and plunge-dives in coastal bays and lagoons.