Immediate challenges and costs of elevational shifts in mountain lizards evaluated through reciprocal translocation

Animals are known to move across elevations in response to climate change. However, the costs and challenges associated with these movements are not well-understood. Therefore, it is essential to explore how animals respond to a novel elevation to comprehensively understand their strategies for mitigating the effects of climate change. In this study, we examined fitness-related traits of the high-elevation toad-headed agama (Phrynocephalus vlangalii) on the Qinghai-Xizang Plateau following elevational translocation using a 2 (population origins) × 2 (elevational environments) design. We switched lizards between habitats at 2600 and 3600-m elevation, assessing their body condition, home ranges, behavioural thermoregulation, thermal physiology, locomotor performance and resting metabolic rates at both native and translocation sites. We found that the lizards from the 3600 m a.s.l. performed equally well at both 2600-m and 3600-m elevation sites. In contrast, the lizards from the 2600 m a.s.l. performed well at their native elevation but struggled at the 3600-m site, indicated by decreased accuracy and effectiveness of thermoregulation, reduced locomotion and resting metabolic rates, shrunken home ranges and a significant decline in body condition. Our study highlights the challenges and costs animals face when moving to higher elevations to escape the impacts of climate change. It also emphasizes the importance of assessing immediate responses to novel environments when evaluating the efficacy of dispersal as a buffering strategy against climate change.