Diurnal migration patterns in willow warblers differ between the western and eastern flyways.

ABSTRACT: It is a long-standing view that the main mechanism maintaining narrow migratory divides in passerines is the selection against intermediate and suboptimal migratory direction, but empirical proof of this is still lacking. We present novel results from a willow warbler migratory divide in central Sweden from where birds take the typical SW and SE as well as intermediate routes to winter quarters in Africa. We hypothesized that individuals that take the intermediate route are forced to migrate in daytime more often when crossing wide ecological barriers than birds that follow the typical western or eastern flyways. Analyses of geolocator tracks of willow warblers breeding across the entire Sweden, including the migratory divide, provided no support for our hypothesis. Instead, birds that mig

SUBMITTER: Sokolovskis K 

PROVIDER: S-EPMC10512566 | biostudies-literature | 2023 Sep

REPOSITORIES: biostudies-literature