engleski

Southwest or southeast? Migration patterns and conectivity in the Reed Warbler

Eurasian Reed Warbler (Acrocephalus scirpaceus) is a long-distance migrant breeding in wetlands of western and central Palaearctic and wintering in sub-Saharan Africa. We used all available recoveries to outline the migration patterns and migratory connectivity of the species. In addition, we employed stable isotope analysis as an indirect approach to infer the wintering origin of 15 European populations. Ringing recoveries showed that Reed Warblers from Western and Northern Europe and northern parts of Central and Eastern Europe use the western Mediterranean flyway, pass through Iberia and enter Africa via Morocco or Algeria. Birds breeding in the Pannonian plain and on the western Black Sea coast head initially southeast passing through the eastern Mediterranean, entering Africa through Egypt or eastern Libya. Birds migrating in the two general directions meet in southern Central Europe (and probably in Italy) where a migratory divide occurs. The sub-Saharan recoveries show two main clusters which refer to the two main migratory directions (SW-migrating birds winter from Senegal to western Nigeria, SE-migrating birds in the Lake Chad basin). In addition, recoveries in Senegambia show relatively high migratory connectivity of British and Iberian Reed Warblers. Values of carbon and nitrogen stable isotopes from feathers grown in Africa varied considerably within populations and greatly overlapped between populations, suggesting that very different habitats are used during moult. Delta15N values, however, differed significantly between SW- and SE-migrating populations, indicating some separation of the winter quarters in birds using the two general migratory flyways.

migration patterns; connectivity; Reed warblers

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