Migrates from Arctic to Antarctic — among the longest migrations of any animal.

Also called: Sea Swallow

Native status: Native; circumpolar Arctic breeder

§ Quick facts

SizeBody 33–39 cm (13–15 in); wingspan 76–85 cm
Weight86–127 g (3.0–4.5 oz)
LifespanWild 20+ years; oldest documented 34
OrderCharadriiformes
FamilyLaridae

§ Encyclopedia

The Arctic tern is a tern in the family Laridae. This bird has a circumpolar breeding distribution covering the Arctic and subarctic regions of Europe, Asia, and North America. The species is strongly migratory, seeing two summers each year as it migrates along a convoluted route from its northern breeding grounds to the Antarctic coast for the southern summer and back again about six months later. Recent studies have shown average annual round-trip lengths of about 70,900 km (38,300 nmi) for birds nesting in Iceland and Greenland, and about 48,700 km (26,300 nmi) for birds nesting in the Netherlands, while an individual from the Farne Islands in Northumberland with a light level geolocator tag covered a staggering 96,000 km (52,000 nmi) in ten months from the end of one breeding season to the start of the next. These are by far the longest migrations known in the animal kingdom.

Source: Wikipedia — Arctic tern Licensed under CC BY-SA 4.0

§ Identification

Field marks. Slender white-and-gray tern with deeply forked tail; black cap; entirely red bill (vs. Common Tern's black tip). Short legs.

Similar species. Common Tern (black bill tip). Forster's Tern (white face in winter). Roseate Tern (longer tail streamers, pinker bill).

Voice. Sharp ringing "kee-arr" and rapid chattering at colonies.

§ Diet & behavior

Diet. Small fish (sandeel, capelin, herring), crustaceans, insects caught at sea by plunge-diving and surface-snatching.

Behavior. Performs the longest annual migration of any animal — ~70,000 km between Arctic breeding grounds and Antarctic wintering grounds, experiencing two summers per year and more daylight than any other animal. Nests colonially on bare ground or rock; aggressive nest defense includes dive-bombing intruders.

§ Range

Arctic; winters Antarctic

§ Habitat

Coastal areas, open ocean

§ Threats

Climate change, ocean pollution.

§ Conservation status

According to the IUCN Red List, the arctic tern is currently classified as Least Concern.

§ What helps

Support both polar conservation. Reduce ocean plastic.

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§ Further reading

§ Sources cited

  • Cornell Lab — All About Birds
  • British Antarctic Survey migration studies
  • IUCN Red List 2018