Philopatry of winter moult area in migratory great reed warblers Acrocephalus arundinaceus demonstrated by stable isotope profiles

Abstract in Undetermined Stable carbon- (delta(13)C), nitrogen- (delta(15)N) and hydrogen (delta D) isotope profiles in feathers of migratory Great Reed Warblers Acrocephalus arundinaceus recaptured for 2 or more years in 6 successive years were examined to test whether the isotope profiles of individual warblers appeared to be consistent between years. Similar isotopic signatures in successive years suggested that individual birds tended to return and grow their feathers in Afro-tropical wintering habitats that generate similar delta(13)C, delta(15)N and delta D signatures. Previous studies have shown that Great Reed Warblers exhibit strong natal and breeding philopatry, with most of the surviving birds returning to the breeding site. The present study of feather delta(13)C, delta(15)N and delta D isotopic values demonstrate the year-to-year fidelity might also include the African moulting sites in this migratory species