Bridled Tern Onychoprion anaethetus
Gaivina-de-dorso-castanho (Garajau-de-dorso-castanho)
2009-05-24
1 mile north of Manhenha lighthouse, Pico
© Joćo Quaresma, Portugal
Birding Azores
The photo is much enlightened for showing plumage details.

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