Forecasting the response to global warming in a heat-sensitive species

Avoiding hyperthermia entails considerable metabolic costs for endotherms. Such costs increase in warm conditions, when endotherms may trade food intake for cooler areas to avoid heat stress and maximize their energy balance. The need to reduce heat stress may involve the adoption of tactics affecting space use and foraging behaviour, which are important to understand and predict the effects of climate change and inform conservation. We used resource selection models to examine the behavioural response to heat stress in the Alpine ibex (Capra ibex), a cold-adapted endotherm particularly prone to overheating. Ibex avoided heat stress by selecting the space based on the maximum daily temperature rather than moving hourly to ‘surf the heat wave’, which minimised movement costs but prevented optimal foraging. By integrating these findings with new climate forecasts, we predict that rising temperatures will force mountain ungulates to move upward and overcrowd thermal refugia with reduced ca...规避体温过热对内温动物（endotherms）而言需付出高昂的代谢成本。在温热环境中，此类成本会进一步攀升，此时内温动物可能会牺牲食物摄入，转而前往温度更低的区域以规避热应激，并最大化自身能量平衡。降低热应激的需求可能促使动物采取影响空间利用与觅食行为的策略，而理解这些策略对于认识、预测气候变化的影响并为保护工作提供依据至关重要。我们借助资源选择模型，研究了阿尔卑斯羱羊（Capra ibex）——一种特化适应寒冷、极易发生体温过热的内温动物——对热应激的行为响应。羱羊通过依据日最高气温选择活动空间来规避热应激，而非逐时‘跟随热浪’移动，该策略虽降低了移动成本，却无法实现最优觅食。通过将上述研究结果与最新气候预测相结合，我们预测，气温上升将迫使山地有蹄类动物向更高海拔迁移，并在热避难所内出现过度拥挤的状况，且伴随……（原文此处内容截断）