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Bonaparte’s Gull – (Chroicocephalus philadelphia)

gullDainty and petite are not words typically used for gulls, but these are not typical gulls. Bonaparte’s Gulls are the smallest gulls commonly found in North America, measuring a tiny 12” from bill to tail. Their overall structure is also very petite, with a slim white body, angular gray wings, a short bill, and a cute, rounded head with a dark ear smudge. Their flight style is distinctively buoyant, and they flash white stripes on the upperwings that draw the eye. Rather than hanging around parking lots for handouts, Bonaparte’s Gulls spend their time along lakes and rivers.

Bonaparte’s Gulls feed on aquatic food that floats to the surface. They are highly gregarious, normally found in feeding flocks of dozens of birds. On Portage Lake, they sometimes follow foraging Common Loons, in order to feed on fish and invertebrates fleeing the diving loons. This foraging method creates an entertaining up-down rhythm, as the flock of Bonaparte’s Gulls dive to the surface when the loon slips underwater and take flight when the loon reappears on the surface.

Bonaparte’s Gulls are winter birds around the Chain of Lakes. They spend their summers on the tundra, building nests in trees (a rare habit for a gull) and feeding in boreal bogs and lakes. When the lakes freeze over further north, they fly south and concentrate along lakes, rivers, and bays, particularly near nutrient upwellings or outlets that offer plentiful food. In migration, they will even forage in agricultural fields or prairies, feeding on insects and even digging for earthworms.

Bonaparte’s Gulls were discovered in Philadelphia, giving it the scientific name Chroicocephalus philadelphia, and was named in honor of Charles Lucien Bonaparte, a prominent ornithologist and the cousin of Napoleon Bonaparte. Chroicocephalus translates as khroizo, to stain (Greek), and -kephalos, headed (Greek), making the scientific name “Stain-headed Philadelphia.”

Further Reading:

Click Here for the All About Birds entry.
Click Here for A humorous overview of the Bonaparte’s Gull, including the full story of its name.
Click Here for information from Birds of North America
Earthworms Anecdote: Eaton, E. H. 1914. Birds of New York State. New York State Mus. Albany.

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