caa a22 4500 463176340 CHVBK 20180406164827.0 cr unu---uuuuu 170326e20070401xx s 000 0 eng 10.1007/s10336-007-0130-8 doi (NATIONALLICENCE)springer-10.1007/s10336-007-0130-8 Sex differences in settlement behaviour and condition of chiffchaffs Phylloscopus collybita at a wintering site in Portugal. Are females doing better? [Elektronische Daten] [Paulo Catry, Stuart Bearhop, Miguel Lecoq] In passerine birds, males are generally larger and dominant over females. In line with the dominance theory, in all known differential migrant passerines, females migrate further than males. However, there are alternative explanations to the dominance hypothesis, including the specialisation hypothesis, predicting that females should do better than males in habitats and/or regions to which they are specially adapted, and where they predominate in numbers. Few studies have aimed at comparing the behaviour and condition of males and females wintering in locations largely dominated by female birds. We studied a partly nomadic species, the common chiffchaff Phylloscopus collybita, at a wintering site in Portugal. Most individuals caught at this site were transients. The only consistent and relatively powerful predictor of settlement behaviour was sex. Almost all the birds that settled in the study area were female, while there was an almost even sex ratio in the transient sample. Females had higher muscle and post-juvenile moult scores when first captured. In addition, there was a significant sex-based difference in mass trajectories, with females maintaining body mass and males losing body mass when settled at the study site. Results from this study suggest that the poor performance of males was either due to inferior male competitive ability in a region/habitat where females predominate and/or it resulted from the fact that males that reach these wintering grounds are of inferior individual quality. Dt. Ornithologen-Gesellschaft e.V., 2007 Differential migration nationallicence Dominance nationallicence Sexual segregation nationallicence Catry Paulo Unidade de Investigação em Eco-Etologia, Instituto Superior de Psicologia Aplicada, Rua Jardim do Tabaco 44, 1149-041, Lisboa, Portugal aut Bearhop Stuart Centre for Ecology and Conservation, School of Biosciences, University of Exeter, Cornwall Campus, TR10 9EZ, Penryn, UK aut Lecoq Miguel Sociedade Portuguesa para o Estudo das Aves, No. 53, 3° Esq., 1100-618, Lisboa, Portugal aut Journal of Ornithology Springer-Verlag 148/2(2007-04-01), 241-249 0021-8375 148:2<241 2007 148 10336 https://doi.org/10.1007/s10336-007-0130-8 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10336-007-0130-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Catry Paulo Unidade de Investigação em Eco-Etologia, Instituto Superior de Psicologia Aplicada, Rua Jardim do Tabaco 44, 1149-041, Lisboa, Portugal aut NATIONALLICENCE 700 1- Bearhop Stuart Centre for Ecology and Conservation, School of Biosciences, University of Exeter, Cornwall Campus, TR10 9EZ, Penryn, UK aut NATIONALLICENCE 700 1- Lecoq Miguel Sociedade Portuguesa para o Estudo das Aves, No. 53, 3° Esq., 1100-618, Lisboa, Portugal aut NATIONALLICENCE 773 0- Journal of Ornithology Springer-Verlag 148/2(2007-04-01), 241-249 0021-8375 148:2<241 2007 148 10336 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer