Seasonal and daily movement patterns of an alpine passerine suggest high flexibility in relation to environmental conditions

Mountains naturally offer variable habitat conditions, but their biodiversity is currently facing the extra challenge of adapting to rapid environmental shifts that are much more pronounced than in the lowlands. Among adaptive responses, intra- and inter-seasonal movements represent potentially important coping strategies for wildlife that remain largely unexplored. We investigated the seasonal and daily movements of the ring ouzel Turdus torquatus, a European mountain bird species that is declining in many parts of its distribution. We tracked individuals breeding in the Swiss Alps using light-level geolocators and multi-sensor loggers. Of the birds traced to their non-breeding grounds, two thirds reached the Atlas Mountains while one third stayed in Spain, a region potentially more significant for overwintering than previously thought. The birds remained mostly above 1000 m throughout the annual cycle, highlighting a strict association of ring ouzels with mountain habitats. We also evidenced flexible daily elevational movements, especially upon spring arrival on the breeding grounds in relation to date and snowfall occurrence, suggesting adaptive potential in response to environmental variation. This study shows how modern technology can deliver deeper and valuable insights into movements, behavioural patterns, and life-history strategies for relatively little-studied animal species. By doing so, it paves the way for refined assessments of species' vulnerability to ongoing global change while providing basic conservation guidance.See README.txt file Funding provided by: Swiss Federal Office for the Environment*Crossref Funder Registry ID: Award Number: 254, 332, 363, 400Funding provided by: Swiss Federal Office for the EnvironmentCrossref Funder Registry ID: http://dx.doi.org/10.13039/501100003338Award Number: 254, 332, 363, 400Data from geolocators (GDL2 & GDL-uTag, Swiss Ornithological Institute) and multi-sensor loggers (GDL3-PAM, Swiss Ornithological Institute) fitted using leg-loop harnesses on Alpine Ring Ouzels (Turdus torquatus alpestris) breeding in the Swiss Alps. There is both raw data (light intensity, pressure, acceleration, magnetism) and data on classified twilight events and estimated migratory tracks (coordinates with uncertainty and fitted models)