Differential timing and latitudinal variation in sex ratio of Aquatic Warblers during the autumn migration
Katarzyna Wojczulanis-Jakubas , Małgorzata E. Chrostek , Frédéric Jiguet , Carlos Zumalacárregui Martínez , David Miguélez , Júlio M. Neto
AbstractDifferential migration has been extensively reported in spring, but less so in autumn, particularly in relation to sex in monomorphic bird species. Here, we analysed the autumn passage of a monomorphic, globally threatened passerine, the Aquatic Warbler Acrocephalus paludicola throughout Western Europe, with regard to age and sex. We showed that, overall, adults migrated earlier than first-year birds, and males migrated earlier than females during the autumn migration. This may be caused by an overall social dominance of adults over immatures, and differentiated migration strategy of males and females. In addition, we found male-skewed sex proportions, with a tendency to an equalised ratio in more southern stopover sites. This may indicate a male bias in the global population or different migration strategies of the sexes. Differential migration may cause the age and sex classes to be exposed differently to various threats affecting demographic structure of the species.
|Journal series||Naturwissenschaften, ISSN 0028-1042|
|Publication size in sheets||0.5|
|Keywords in English||Acrocephalus paludicola, migration strategy, sex proportion|
|Score|| = 30.0, 26-02-2018, ArticleFromJournal|
= 35.0, 26-02-2018, ArticleFromJournal
|Publication indicators||: 2016 = 1.191 (2) - 2016=1.191 (5)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.