An unexpected pattern of migration revealed in the Subalpine Warbler Sylvia cantillans complex by mitochondrial DNA analyses

Genetic markers are often used to trace the geographical origin of migrating birds. Such an approach has been used to attribute individuals of a given species to a given population, but it could also be applied to cryptic species, which are not fully diagnosable on the basis of their morphological appearance alone, despite often being genetically distinct. We sampled migrants of the Sylvia cantillans complex, which include cryptic taxa not readily identified on the basis of their appearance, at spring stopover sites in the central Mediterranean. We identified these individuals taxonomically using mitochondrial DNA sequence data. Molecular analyses enabled us to establish that four different taxa/clades of the Sylvia cantillans complex (two S. c. cantillans clades, S. c. albistriata and S. subalpina) migrate through the central-western Mediterranean from Africa. \ua9 2012 The Authors. Ibis \ua9 2012 British Ornithologists' Union