European Herring Gull, Larus argentatus

"IMG_4819" by Gulli H via Flickr, Creative Commons Attribution-NoDerivs.

Common Gull, Larus canus

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Ring-billed Gull, Larus delawarensis

"Ring-billed Gull LMO 7-15-09" by THE Holy Hand Grenade! via Flickr, Creative Commons Attribution-NoDerivs.

Lesser Black-backed Gull, Larus fuscus

"Gaviota sombría Larus fuscus" by Agpov via Flickr, Creative Commons Attribution.

Great Black-backed Gull, Larus marinus

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Western Gull, Larus occidentalis

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