Family Gulls, Terns, Skimmers (Laridae)

Least Concern

Grey-backed Tern (Onychoprion lunatus)


French: Sterne à dos gris German: Brillenseeschwalbe Spanish: Charrán lunado
Other common names: Spectacled Tern

Sterna lunata


, 1848,

Tuamotu Islands


Formerly united with O. fuscatus and O. anaethetus in separate genus Haliplana. Monotypic.


Northern Mariana Is E through Wake I and N Marshall Is to Hawaiian Is, and S through Phoenix and Line Is to Fiji, then E to Tuamotu Is and Austral Is; possibly formerly at Easter I; possibly also Samoa and Society Is. Wanders irregularly W to N Moluccas.

Descriptive notes

38 cm; 115–177 g; wingspan 73–76 cm. Somewhat reminiscent of O. fuscatus, but with grey upperparts and upperwings; white forehead patch smaller, but... read more


Noisy at colonies. Most frequent call is a squeaky "bee-doo-bee-doo". Also gives a range of... read more


Oceanic islands of the tropical Pacific, breeding on low sea cliffs, sandy beaches or bare ground... read more

Food and feeding

Mainly small fish, e.g. clupeids and flying-fish (Exocoetidae), and squid. In the Hawaiian Islands the diet has been found to include fish... read more


The breeding period is very extended and breeding is reported all year round at some locations. At Johnston Atoll first eggs are usually... read more


Abandons colonies after nesting and ranges in oceanic waters of the Pacific. The marine range... read more

Status and conservation

Not globally threatened (Least Concern). The global population is not known with any precision and is placed within the range of 100,000 to 1 million individuals. Counts and... read more

Recommended citation

Gochfeld, M., Burger, J. & Garcia, E.F.J. (2020). Grey-backed Tern (Onychoprion lunatus). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from on 28 February 2020).