Arctic Tern vs Eastern Bluebird
Sterna paradisaea so với Sialia sialis
Side-by-Side Comparison
| Thuộc Tính | Arctic Tern | Eastern Bluebird |
|---|---|---|
| Tên Khoa Học | Sterna paradisaea | Sialia sialis |
| Bộ | Charadriiformes | Passeriformes |
| Họ | Laridae | Turdidae |
| Tình Trạng Bảo Tồn | Least Concern | Least Concern |
| Chiều Dài | 34,0 cm (13.4 in) | 17,5 cm (6.9 in) |
| Chiều Dài Sải Cánh | 80,0 cm (31.5 in) | 27,0 cm (10.6 in) |
| Khối Lượng | 110,0 g (3.88 oz) | 31,0 g (1.09 oz) |
| Chế Độ Ăn | Small fish and crustaceans caught by plunge-diving from the air. Hovers briefly before diving. | Insects in summer, berries in winter. Hunts from low perches, dropping to the ground to … |
| Số Trứng | 2-3 | 4-5 |
| 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.
Eastern Bluebird
Open woodland, farmland edges, orchards, and parks with scattered trees and open ground. Readily uses nest boxes.
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.
Eastern Bluebird
A rich, melodious warbled 'chur-wi, tur-a-lee' song. Both sexes sing. Call is a soft, musical 'turee'. Song is gentle and flute-like, suggesting a small thrush. Given from exposed perch.
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.
Eastern Bluebird
Eastern North America from southern Canada to Honduras and Nicaragua. Partially migratory.
Tình Trạng Bảo Tồn
Arctic Tern
Eastern Bluebird
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
Eastern Bluebird
Males are vivid royal blue above with a rusty-red breast and white belly. Females are grey-blue with a paler rust breast.
Short, thin, dark bill
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.
Eastern Bluebird
The eastern bluebird is a beloved symbol of happiness in North America. Once declining due to habitat loss and competition from introduced species, populations recovered dramatically thanks to a massive citizen science nest box campaign. These gentle thrushes form loose winter flocks and huddle together in nest boxes during cold snaps.