Family Gulls, Terns, Skimmers (Laridae)

Least Concern

Bonaparte's Gull (Larus philadelphia)


French: Mouette de Bonaparte German: Bonapartemöwe Spanish: Gaviota de Bonaparte

Sterna Philadelphia


, 1815,

Philadelphia, Pennsylvania, USA


Some recent authors place this species, along with L. genei, L brunnicephalus, L. ridibundus, L. serranus, L. maculipennis, L. hartlaubii, L. cirrocephalus, L. novaehollandiae and L. bulleri, in genus Chroicocephalus (the “masked gulls”)#R#R#R; within that group, present species and L. genei found to be basal#R#R. Monotypic.


W Alaska and S British Columbia E to E Quebec (SE Canada), and possibly N Maine (NE USA). Winters along Pacific coast S to Mexico (Nayarit) and on Atlantic coast to Florida and Greater Antilles; in mild winters, from Great Lakes to Gulf of Mexico.

Descriptive notes

28–34 cm; 170–230 g; wingspan 78–90 cm. Two-year gull. In all plumages very like L. ridibundus, but noticeably smaller, with smaller, black bill;... read more


Calls are tern-like with a distinctive rasping quality and generally higher-pitched than L.... read more


A boreal breeder with distinct breeding and wintering ranges. Breeds at ponds or muskeg in... read more

Food and feeding

Small fish, euphausiids, amphipods, and insects. In British Columbia, euphausiids comprised at least 93% of biomass in spring. On Long I,... read more


Arrives in early May; lays late May. Non-colonial, but nests often clumped, with a few pairs in 1 km². Nests in coniferous trees,... read more


Leaves breeding grounds in August in loose flocks, coalescing into larger groups on reaching coast... read more

Status and conservation

Not globally threatened (Least Concern). Estimated world population 85,000–175,000 pairs based on averages of Christmas Bird Counts, with 19% migrating to Pacific, 21%... read more

Recommended citation

Burger, J., Gochfeld, M., Kirwan, G.M. & Garcia, E.F.J. (2020). Bonaparte's Gull (Larus philadelphia). 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 18 February 2020).