Bonaparte's Gull Similar Species Comparison
Main SpeciesBonaparte's Gull
Breeding adult
Small gull with a thin black bill. Breeding adults have an entirely black head with thin white eye crescents and red legs.
© Jim Sims / Macaulay LibraryBritish Columbia, July 10, 2020Nonbreeding adult
Small and delicate looking gull with a thin black bill. Nonbreeding adults have a black smudge behind the eye and pink legs.
© Evan Lipton / Macaulay LibraryMassachusetts, November 03, 2016Breeding adult and immature
Found along lakes, rivers, marshes, bays, and beaches. Note thin black bill, dark hood on the adult, and black ear patch on the immature.
© Jay McGowan / Macaulay LibraryNew York, May 15, 2015Not all videos have sound
First winter
First winter birds have a black smudge behind the eye and a black bar across the wings that is visible on resting and flying birds.
© Brandon Holden / Macaulay LibraryOntario, November 08, 2005Juvenile
Juveniles are a patchwork of brown and gray, but note the dark spot behind the eye.
© Jay McGowan / Macaulay LibraryNew York, August 25, 2019Nonbreeding adult
In flight, nonbreeding adults have a white tail and black tips on the primaries.
© Darren Clark / Macaulay LibraryIdaho, November 03, 2018First winter
First winter birds show the characteristic "M" pattern on the back and have pale underwings, only showing black on the tips of the feathers. Note black tail band.
© Alan Wells / Macaulay LibraryFlorida, February 03, 2020Juvenile
Juveniles have a black "M" pattern with a mottled brown-and-gray body.
© Brandon Holden / Macaulay LibraryOntario, August 06, 2007First summer
First summer birds start to acquire black feathers on the head. Note dark spot behind the eye.
© Jay McGowan / Macaulay LibraryNew York, June 08, 2015Habitat
Breeds around lakes and marshes in the boreal forest. Winters along lakes, rivers, marshes, bays, and beaches along the coast.
© Kate Caldwell / Macaulay LibraryAlberta, July 26, 2017Similar SpeciesLittle Gull
Breeding adult
Adult Little Gulls have dark underwings unlike the all-white underwings of Bonaparte's Gulls.
© Ian Davies / Macaulay LibrarySouth Karelia, June 07, 2015Similar SpeciesLittle Gull
Nonbreeding adult
Nonbreeding adult Little Gulls have gray wings, whereas nonbreeding and breeding Bonaparte's Gulls have black-tipped primaries.
© Brandon Holden / Macaulay LibraryOntario, November 08, 2005Similar SpeciesLittle Gull
First summer
First-summer Little Gulls have the trailing edge of the wing tipped in white, not black like first-winter and juvenile Bonaparte's Gulls.
© Yann Kolbeinsson / Macaulay LibraryNorðurland eystraSimilar SpeciesLittle Gull
Juvenile
Juvenile Little Gulls have a bolder and thicker "M" pattern on the back than juvenile Bonaparte's Gulls.
© Nick Saunders / Macaulay LibrarySaskatchewan, October 13, 2013Similar SpeciesBlack-headed Gull
Breeding adult
Black-headed Gulls are larger and bulkier than Bonaparte's Gulls. Breeding adults have a dark red bill, not black like Bonaparte's Gulls.
© Paul Tavares / Macaulay LibrarySuðurland, July 06, 2011Similar SpeciesBlack-headed Gull
Breeding adult
Black-headed Gulls have dark primaries as seen from below, unlike Bonaparte's Gulls, which have pale underwings.
© Ian Davies / Macaulay LibraryNorrbottens län [SE-25], June 19, 2015Similar SpeciesBlack-headed Gull
Nonbreeding adult
Nonbreeding and breeding Black-headed Gulls have a reddish bill, whereas Bonaparte's Gulls have a black bill at all ages.
© Shawn Billerman / Macaulay LibraryNew York, December 30, 2016Similar SpeciesBlack-headed Gull
Immature
Black-headed Gulls are larger and bulkier than Bonaparte's Gulls. Immatures have a reddish bill unlike Bonaparte's Gulls, which have a black bill at all ages.
© Bruce Kerr / Macaulay LibraryScotland, November 03, 2013Similar SpeciesBlack-headed Gull
Immature
In flight, immature Black-headed Gulls have a less distinct "M" pattern on the wings than immature Bonaparte's Gulls.
© Patrick J. Blake / Macaulay Libraryİstanbul, December 25, 2015Similar SpeciesBlack-legged Kittiwake
Nonbreeding adult
Breeding and nonbreeding adult Black-legged Kittiwakes have a yellow bill unlike Bonaparte's Gulls, which have a dark bill.
© Matt Brady / Macaulay LibraryCalifornia, February 08, 2012Similar SpeciesBlack-legged Kittiwake
Immature
Immature Black-legged Kittiwakes have a black collar on the back of their necks that immature Bonaparte's Gulls lack.
© Evan Lipton / Macaulay LibraryMassachusetts, November 10, 2015Similar SpeciesRoss's Gull
Nonbreeding adult
Ross's Gulls have a shorter bill than Bonaparte's Gulls. Nonbreeding adults have one smudgy spot behind the eye, whereas nonbreeding Bonapartes tend to have two smudgy spots, one behind and one above the eye.
© Brian Sullivan / Macaulay LibraryCalifornia, January 12, 2017Similar SpeciesRoss's Gull
First winter
Ross's Gulls have a wedge-shaped tail unlike Bonaparte's Gulls. First-winter gulls have white trailing edges on their wings, whereas first-winter Bonaparte's Gulls have black trailing edges.
© Ian Davies / Macaulay LibraryNew York, January 29, 2017Similar SpeciesRoss's Gull
First winter
From below Ross's Gulls have gray primaries, whereas Bonaparte's Gulls have white primaries.
© Ian Davies / Macaulay LibraryNew York, January 29, 2017Similar SpeciesSabine's Gull
Breeding adult
Sabine's Gulls have a black leading edge of the wing, whereas Bonaparte's Gulls have a white leading edge and black-tipped primaries. Also note the yellow-tipped black bill on Sabine's, but not on Bonaparte's.
© Ryan Merrill / Macaulay LibraryWashington, August 23, 2009Rotate Your Device to Better Compare
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Species in This Family
Gulls, Terns, and Skimmers(Order: Charadriiformes, Family: Laridae)
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