EV-1 Timing of migration and residence areas during the non-breeding period of barn swallows Hirundo rustica in relation to sex and population Felix Liechti, Chiara Scandolara, Diego Rubolini, Roberto Ambrosini, Fränzi Korner-Nievergelt, Steffen Hahn, Roberto Lardelli, Maria Romano, Manuela Caprioli, Andrea Romano, Beatrice Sicurella and Nicola Saino F. Liechti (felix.liechti@vogelwarte.ch), C. Scandolara, F. Korner-Nievergelt, S. Hahn and R. Lardelli, Swiss Ornithological Inst., Seerose 1, CH-6204 Sempach, Switzerland. – CS, D. Rubolini, R. Ambrosini, M. Romano, M. Caprioli, A. Romano and N. Saino, Dept of Biosciences, Univ. of Milan, via Celoria 26, IT-20133 Milano, Italy. – B. Sicurella, Dept of Biotechnology and Biosciences, Univ. of Milano-Bicocca, p.zza della Scienza 2, IT-20126 Milano, Italy. We investigated sex- and year-dependent variation in the temporal and spatial movement pattern of barn swallows Hirundo rustica during the non-breeding period. Hundred and three individuals equipped with miniaturized light-level geolocators at three diferent breeding areas in southern Switzerland and northern Italy provided data for the analysis. We identiied a region 1000 km in radius centred in Cameroon as the main non-breeding residence area of these three geographical populations. Five residence areas of males only were in southern Africa, south of 19°S. Most individuals occupied a single site during their stay south of the Sahara. he timing of migration broadly overlapped between sexes and all geographical breeding populations. Between the two study years there was a distinct diference of 5 to 10 d in departure dates from and arrival at the breeding sites. Remarkably, the period of residence in sub-Saharan Africa was very similar (157 d) in the two study years, but their positions in the irst year (2010–2011) were about 400 km more to the north than in the second (2011–2012). Independent of the year, individuals with sub-Saharan residence areas further north and east had a shorter pre-breeding migration and arrived earlier than those staying further south and west. In addition, birds breeding in south- ern Switzerland arrived at their breeding colony 7–10 d later than those breeding only 100 km south, in the Po river plain. Our study provides new information on the variance in migration phenology and the distribution of residence areas in sub-Saharan Africa in relation to sex, population and year. It supports the usefulness of light-level geolocators for the study of annual routines of large samples of small birds. Palearctic songbirds make up the vast majority of the two billion birds migrating every autumn from Europe into sub-saharan Africa (Hahn et al. 2009). Species-speciic non- breeding ranges in sub-Saharan Africa are roughly identi- ied, mostly by ring recoveries (Walther and Rahbek 2002), whereas population-speciic whereabouts and individual histories of residences during the non-breeding period are hardly known. he recent miniaturization of individual tracking systems has now opened up the possibility to moni- tor the year-round movements of the small songbird species (Bridge et al. 2013). Individual-based information is pivotal to our under- standing of the evolution of migration. Such data will allow dissecting the genetic and phenotypically plastic compo- nents of migratory behaviour, and also to predict how migra- tory species will respond to environmental transformations, including climate change (Gienapp et al. 2007). Only for few species, population-based data on migration derived by large-scale bird ringing projects have provided general information on migration routes and phenology, and on non-breeding distribution (Tautin et al. 1999, Rubolini et al. 2002, Boulet et al. 2006, Ambrosini et al. 2011, Ryder et al. 2011). For the vast majority of migratory bird species studied so far, an individual-based description of the timing and whereabouts during the non-breeding period is not available for a considerable number of individuals from the same breeding population. Even fundamental questions on the role of major potential sources of variation in migratory behaviour, such as sex, geographical position of the breeding area and environ- mental efects, are still far from being resolved. Sex-speciic diferential migration is well-established in several species, where males and females have been shown to adopt difer- ent migration strategies (Cristol et al. 1999, Morbey and Ydenberg 2001). A few comprehensive studies mainly show a certain degree of protandry, in the order of days/few weeks, in pre-breeding migration, based on sex-speciic diferences in migration timing (Swanson et al. 1999, Forstmeier 2002, © 2014 Swiss Ornithological Institute. Journal of Avian Biology © 2014 Nordic Society Oikos Subject Editor: homas Alerstam. Editor-in-Chief: Jan-Åke Nilsson. Accepted 8 October 2014 Journal of Avian Biology 45: 001–012, 2014 doi: 10.1111/jav.00485