Migrants

Located in the subtropical Northeast Atlantic, the archipelago of the Azores represents an ornithological transition between tropical and temperate waters.

It is an important area of regular passage for migratory sea birds, particularly for those that make long migratory flights. This is the case with some species that reproduce in the southern hemisphere, such as the Wilson's storm-petrel Oceanites oceanicus, the Great shearwater Ardenna gravis, the Sooty shearwater Ardenna grisea and the South polar skua Catharacta maccormicki (Ramirez et al. 2008; Koppp et al. 2011; Hedd et al. 2012), and species that nest at higher latitudes in the northern hemisphere, such as the Long-tailed jaeger Stercorarius longicaudus, the Parasitic jaeger Stercorarius parasiticus, the Pomarine jaeger Stercorarius pomarinus and the Arctic tern Sterna paradisaea .

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In Azorean waters, during the autumn migration, there are also records of a large number of Leach's storm-petrel Hydrobates leucorhoa and Red phalarope Phalaropus fulicarius and a few individuals of Sabine's gull Xema sabini and Black-legged kittiwake Rissa tridactyla (Stenhouse et al. 2011; Fredericksen et al. 2011).