Common tern

Sterna hirundo hirundo

Family: Laridae

Length: 31 – 39 cm
Wingspan: 72 – 98 cm
Weight: 90 – 165 g

Credit photo: Ken Billington


Appearance: medium-sized seabird with light grey upperparts, white to very light grey underparts, black cap, orange-red legs, narrow pointed red bill with a black tip at the end.

Distinguishing characteristics: black tip at the end of the red bill.

Flight: smooth, fast and elegant.

Sound: wide repertoire of calls such as high and grating « kee-yah », « kye-kye-kye-kye… » or characteristic « kirri-kirri ».

Ecology and habitat

Nest: breeds on exposed rocky cliffs, offshore islands or islets.  

Diet: feeds primarily on fish, also molluscs, crustaceans and other invertebrates.

Behaviour at sea: coastal species, rarely occurring inland and generally not travelling far offshore.

* This map indicates coastal nesting sites in the Mediterranean and adjacent Seas.

Distribution and movement

Breeding: the species is cosmopolite; the subspecies Sterna hirundo hirundo breeds within the European continent inland (rivers and lakes) or on the coast (rocky islets, beaches and on the edge of marshes).

Wintering: off the coast of Africa.

Phenology: incubation: 21-25 days; two or three eggs. Fledging: 22-28 days.


Global population estimate: European population: 316,000 – 605,000 pairs.

Threats: habitat loss, colony disturbance, predation and pesticides.

Protection level: Barcelona Convention : Annex II; Bern Convention : Annex II; Birds Directive : Annex I; IUCN Red List: Least Concern.

Some key references

BirdLife International (2021) Species factsheet: Sterna hirundo.

Kralj J., Martinović M., Jurinović L., Szinai P., Sütő S., Preiszner B. 2020. Geolocator study reveals east African migration route of Central European Common Terns. Avian Research 11(1): 1-11.

Scarton F. 2010. Long term decline of a Common Tern (Sterna hirundo) population nesting in salt marshes in Venice lagoon, Italy. Wetlands 30(6): 1153-1159.