Main content area

Birds of a feather winter together: migratory connectivity in the Reed Warbler Acrocephalus scirpaceus

Procházka, Petr, Hobson, Keith A., Karcza, Zsolt, Kralj, Jelena
Journal für Ornithologie 2008 v.149 no.2 pp. 141-150
Acrocephalus, arid zones, birds, breeding, breeding sites, carbon, cluster analysis, ecosystems, feathers, migratory behavior, nitrogen, stable isotopes, winter, Europe, Sub-Saharan Africa
To investigate migratory connectivity in the Reed Warbler Acrocephalus scirpaceus, we analysed (1) all available sub-Saharan ringing recoveries and (2) stable isotopes in feathers grown in Africa sampled at 17 European breeding sites across a migratory divide. A cluster analysis of ringing recoveries showed remarkable connectivity between breeding and non-breeding grounds. Two main clusters represented populations taking the two main migratory routes [southwesterly (SW) and southeasterly (SE)]. Stable isotope analysis confirmed the separation of wintering areas of SW- and SE-migrating populations. Higher δ¹⁵N values in feathers of SE-migrating birds indicated that they occupied more xeric biome types. Values of δ¹³C that did not differ significantly among populations were higher than those from feathers of known European origin and indicated a C4 biome. Three populations with an unknown migratory direction were assigned to the SE-migrating populations on the basis of δ¹⁵N values.