Breeding origins and pattern of migration of Bluethroats Luscinia svecica wintering from Iberia to Senegal as revealed by stable isotopes

ABSTRACTCapsule: Stable isotope analyses reveal some degree of migratory connectivity of Bluethroat populations wintering from Iberia to West Africa.Aims: To identify the probable breeding origins of Bluethroats wintering from Iberia to Senegal.Methods: Bluethroat feathers (P1) were sampled from individuals at their wintering areas. These feathers were then analysed for stable H isotopes (δ2H). We assigned individual Bluethroats to approximate geographic origin using likelihood-based assignment procedures.Results: We observed spatial segregation between different Bluethroat populations. At wintering sites north of the Sahara Desert, Bluethroats wintering to the west came from further west origins than those which overwintered to the east. Bluethroats from central-eastern Europe overwintered either within the circum-Mediterranean region or in Senegal. We found no clear evidence supporting a sub-Saharan wintering range for birds breeding in Iberia (Luscinia svecica azuricollis subspecies).Conclusion: North ...