Sempach. - An important basis for the protection and conservation of migratory birds is knowledge about where the birds stay during the year. Thanks to novel geolocators that measure atmospheric pressure, researchers studying the wheatear have now learned more about its migratory behavior and the resting areas it uses. The recorders also revealed astonishing facts about the adaptability of this mountain bird to the high mountains.
Geolocators weigh little more than a gram and therefore open up new opportunities to study the life cycle of "lightweights" among birds such as the wheatear. On their way to the Sahel region of Africa, wheatears apparently make short stopovers on the Mediterranean islands and a longer rest to "refuel" in the heights of the Atlas Mountains. They are mainly on the move at night and at altitudes that vary between 2000 and 4000 meters. The maximum altitude recorded was 5150 meters: a mature performance for a bird weighing only 25 grams.
Furthermore, the study of local movements in the breeding area revealed an unexpected behavior: In order to cope with the difficult conditions in the high mountains when returning in spring, Wheatears fly to the valley during the day to forage during snowfalls and then back to the mountains.
Rime, Y., Nussbaumer, R., Briedis, M., Sander, M. M., Chamberlain, D., Amrhein, V., Helm, B., Liechti, F. & Meier, C. M. (2023). Multi-sensor geolocators unveil global and local movements in an Alpine-breeding long-distance migrant. Movement Ecology, 11:19. https://doi.org/10.1186/s40462’023 -00381-6 .
