About the Authors

Richard A. Holland

rholland@orn.mpg.de

Affiliation Department of Migration and Immuno-Ecology, Max-Planck Institute for Ornithology, Radolfzell, Germany

Martin Wikelski

Affiliation Department of Migration and Immuno-Ecology, Max-Planck Institute for Ornithology, Radolfzell, Germany

Franz Kümmeth

Affiliation e-obs GmbH, Munich, Germany

Carlos Bosque

Affiliation Departamento de Biología de Organismos, Universidad Simon Boíivar, Caracas, Venezuela

Competing Interests

Franz Kummeth is a partner in the firm E-obs, which built the GPS tags used in this study. This does not alter the authors' adherence to PLoS ONE policies on data sharing.

Author Contributions

Conceived and designed the experiments: RAH MW FK CB. Performed the experiments: RAH MW FK CB. Analyzed the data: RAH MW FK CB. Contributed reagents/materials/analysis tools: FK. Wrote the paper: RAH MW FK CB.