The migration systems throughout the world are not equally well studied, Comparison of migration ecology of birds of different systems could be beneficial for understanding the evolution and adaption of migratory behavior, but limited attempt has been made so far. We compared patterns of body mass variation between Willow Warbler (Phylloscopus trochilus) and Arctic Warbler (Phylloscopus borealis), two related and ecologically similar species of leaf warblers with the goal of achieving a better understanding of their differing migration strategies and role of en-route conditions in shaping fuel reserves deposition along the way. The two species have large and partly overlapping breeding ranges across Northern Eurasia, but migrate to different wintering grounds: Trans-Saharan Africa and South-East Asia, respectively. The Willow Warbler and Arctic Warbler trapping data collected according to standard protocols were from 52 and 29 trapping sites respectively, distributed along their migration routes from breeding to wintering grounds. Both species showed a tendency of increasing fuel reserves when facing a barrier to cross. However, Willow Warblers do the increase further in the south, before crossing Mediterranean Sea and Sahara, while only eastern populations of Arctic Warblers showed similar pattern before crossing parts of Pacific Ocean in the North- Eastern part of Flyway. Arctic Warblers during migration over mainland move with low to medium levels of fuel reserves. Our results suggest that data from trapped birds should be used in the scale of flyways, to identify the regions important for refueling of tropical songbird migrants and to decide for conservation priorities.
|Состояние||Опубликовано - 2018|
Рымкевич, Т. А., Ктиторов, П., Шамин, Р., Bairlein, F., & Gibson, L. (2018). Eurasian –African vs Asian Migration systems: comparison of Body Mass Variation in two Leaf Warbler Species during Fall Migration. 260.