Avian seasonal elevational migration is a key life-history strategy for adapting to environmental changes, widely observed across global bird populations. Within elevational migrants, diverse movement strategies have been documented in multiple regions worldwide. In this study, we analyzed beeding species exhibiting pronounced seasonal elevational shifts in the Hengduan Mountains of southwestern China by synthesizing multi-source observational data. We identified distinct migration patterns and quantified their proportional representation. Further, we investigated differential adaptation to climate change among elevational migration strategies by integrating species-specific thermal and precipitation tolerances, seasonal extremes, and shifts in tolerance ranges. Our findings reveal distinct climatic adaptation strategies among elevational migration strategies. Species migrating upward during the breeding season exhibited significantly contracted thermal and precipitation tolerance ranges in the non-breeding season, whereas downward migrants showed no significant seasonal differences in tolerance ranges. Additionally, seasonal changes in thermal and precipitation tolerance ranges influenced the elevational distribution limits of elevational migrants, albeit with contrasting directional effects. These results underscore the importance of seasonal variation in climatic extremes—rather than means—in shaping climatic niches and highlight differential sensitivities to climate change among elevational migration strategies.

Changes after Apr 16, 2026: Updated the public analysis scripts to provide additional clarification and improve the readability of the accompanying data products. Changes include adding clearer explanations of variable names, movement-type labels, and seasonal elevation-difference definitions, as well as simplifying exported derived data tables for easier interpretation.