The common tern is a seabird in the family Laridae. This bird has a circumpolar distribution, its four subspecies breeding in temperate and subarctic regions of Europe, Asia and North America. It is strongly migratory, wintering in coastal tropical and subtropical regions. Breeding adults have light grey upperparts, white to very light grey underparts, a black cap, orange-red legs, and a narrow pointed bill. Depending on the subspecies, the bill may be mostly red with a black tip or all black. There are several similar species, including the partly sympatric Arctic tern, which can be separated on plumage details, leg and bill colour, or vocalisations.
Region
Circumpolar Northern Hemisphere
Typical Environment
Breeds widely along coasts and large inland lakes and rivers across Europe, Asia, and North America. Prefers open, sparsely vegetated islands, beaches, gravel bars, and marsh edges for nesting. Winters along tropical and subtropical shorelines of Africa, South America, the Indian Ocean, Southeast Asia, and Australasia (depending on subspecies). Forages mostly in inshore marine waters, estuaries, lagoons, and sheltered bays, but also over large inland waters. Avoids densely vegetated shores and turbulent offshore waters when feeding.
Altitude Range
Sea level to 2000 m
Climate Zone
Temperate
Ease of Keeping
Beginner friendly: 1/5
The common tern is a long-distance migrant that breeds across temperate and subarctic zones and winters along tropical and subtropical coasts. It is a graceful plunge-diver, often hovering before striking the water for small fish. Colonies can be very noisy, and adults vigorously defend nests by dive-bombing intruders. It is easily confused with the Arctic tern but differs in bill coloration, leg length, and vocalisations.
Twisted head
Adult S. h. hirundo in the harbour of Jyväskylä, Finland
Adult S. h. hirundo in breeding plumage at Nantucket National Wildlife Refuge, Massachusetts
Detail of primary feather
Non-breeding adult in Australia
A pair of juveniles in Marjaniemi, Hailuoto, Finland
Fledgling, Danube delta, Romania
Flying over a pond in England. The head and bill point down during a search for fish.
An adult bringing a sand eel to a juvenile at Nantucket National Wildlife Refuge
Temperament
social and active
Flight Pattern
agile, with rapid wingbeats, hovering and plunge-diving
Social Behavior
Breeds in dense colonies on open ground, often alongside other terns and gulls. Pairs are largely monogamous within a season and perform courtship feeding and aerial displays. Nests are shallow scrapes where both adults incubate and tend chicks. Adults aggressively mob predators near the colony.
Migratory Pattern
Seasonal migrant
Song Description
Vocal repertoire includes sharp, rolling krrree and ki-ki-ki alarm notes and a clear, ringing kip call. Calls are frequent and carry over water, especially around colonies. Flight calls are brisk and slightly rasping compared to the softer Arctic tern.
