Bonaparte's gull • Chroicocephalus philadelphia, Larus philadelphia
{Bonaparte = for Charles Lucien Bonaparte, an ornithologist and member of the Academy of Natural Sciences of Philadelphia in the early 1800's, and nephew of Napoleon I.}
Top left: Bonaparte's gull in winter plumage. Photo by Kevin Smith (Maple Leaf Adventures). Top right: in transitional (between winter and breeding) plumage. Photo by Mike Yip. Bottom: Bonaparte's gull in first winter plumage. Left photo by Caroline Fox (Raincoast Conservation Foundation); right photo by Morgan Hocking.
Identification
Bonaparte's gull is one of the more distinctive gulls found on the Central Coast of BC. It is small (180-225 g, with a 70-80 cm wingspan), and its long wings resemble those of a tern. It has a pale grey back and wings, bright white triangles along the leading edges of the wings, and black wingtips (click here for wing colouring; also see top photo). Its underparts are white, it has reddish-orange legs, and a black bill.
Bonaparte's gull has a black head during the breeding season, with a contrasting white partial eye ring. As it does not breed on the Central Coast, however, look instead for a large dark spot behind each eye. This spot is present in both adult and juvenile winter plumage, and is visible in both photos above. First winter (juvenile) plumage also has a brown bar along the leading edge of each wing (see second photo above) - this is visible when wings are spread and when folded.
Habitat & Range
Bonaparte's gull breeds in boreal and taiga forests of northern Canada and Alaska, where it is found near remote wetland locations. Unlike other gulls, it nests primarily in trees. It winters in areas of Mexico, the Caribbean, and the Gulf Coast, along coasts, in bays, and near freshwater habitats. It can be found on the Central Coast during the fall and spring migration periods.
Find more information at the British Columbia Breeding Bird Atlas here.
Similar Species
The winter plumage of the Bonaparte's gull is similar to the black-legged kittiwake, which is differentiated by a yellow bill and black legs, and a black line at the nape of its neck. It is only found in offshore waters of the Central Coast during the winter.
Bonaparte's gull has long wings similar to those of a tern, though tern wings are still longer and thinner. They also have distinctive forked tails.
Intriguing Info
Bonaparte's gull nests for only a short time between late May and early July. They eat mostly insects during this time, but the rest of the year will also eat other foods such as small fish, krill, and crustaceans.
iNaturalist
https://www.inaturalist.org/taxa/144502-Chroicocephalus-philadelphia
Bonaparte's gull is one of the more distinctive gulls found on the Central Coast of BC. It is small (180-225 g, with a 70-80 cm wingspan), and its long wings resemble those of a tern. It has a pale grey back and wings, bright white triangles along the leading edges of the wings, and black wingtips (click here for wing colouring; also see top photo). Its underparts are white, it has reddish-orange legs, and a black bill.
Bonaparte's gull has a black head during the breeding season, with a contrasting white partial eye ring. As it does not breed on the Central Coast, however, look instead for a large dark spot behind each eye. This spot is present in both adult and juvenile winter plumage, and is visible in both photos above. First winter (juvenile) plumage also has a brown bar along the leading edge of each wing (see second photo above) - this is visible when wings are spread and when folded.
Habitat & Range
Bonaparte's gull breeds in boreal and taiga forests of northern Canada and Alaska, where it is found near remote wetland locations. Unlike other gulls, it nests primarily in trees. It winters in areas of Mexico, the Caribbean, and the Gulf Coast, along coasts, in bays, and near freshwater habitats. It can be found on the Central Coast during the fall and spring migration periods.
Find more information at the British Columbia Breeding Bird Atlas here.
Similar Species
The winter plumage of the Bonaparte's gull is similar to the black-legged kittiwake, which is differentiated by a yellow bill and black legs, and a black line at the nape of its neck. It is only found in offshore waters of the Central Coast during the winter.
Bonaparte's gull has long wings similar to those of a tern, though tern wings are still longer and thinner. They also have distinctive forked tails.
Intriguing Info
Bonaparte's gull nests for only a short time between late May and early July. They eat mostly insects during this time, but the rest of the year will also eat other foods such as small fish, krill, and crustaceans.
iNaturalist
https://www.inaturalist.org/taxa/144502-Chroicocephalus-philadelphia
References
Bonaparte's gull (Larus philadelphia). ARKive.org. Accessed 03/01/2014.
Dunn, J. L. and Alderfer, J. (Eds.). (1999). National Geographic Field Guide to the Birds of North America. (3rd Ed.). Washington, D.C.: National Geographic Society. Pp. 196-197.
Bonaparte's Gull. The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology. Retrieved from the Birds of North America Online. Accessed 02/01/2014.
Authors and editors of page
Kelly Fretwell and Brian Starzomski (2014).
Bonaparte's gull (Larus philadelphia). ARKive.org. Accessed 03/01/2014.
Dunn, J. L. and Alderfer, J. (Eds.). (1999). National Geographic Field Guide to the Birds of North America. (3rd Ed.). Washington, D.C.: National Geographic Society. Pp. 196-197.
Bonaparte's Gull. The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology. Retrieved from the Birds of North America Online. Accessed 02/01/2014.
Authors and editors of page
Kelly Fretwell and Brian Starzomski (2014).