Department of Veterinary Medicine, University of Sassari, Sassari, Italy.
Laboratory of Wildlife Ecology and Behaviour, School of Biology and Environmental Science, University College Dublin, Dublin, Ireland.
Sci Rep. 2019 Feb 28;9(1):3048. doi: 10.1038/s41598-019-39450-5.
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 carrying capacity. Our approach helps in identifying priority areas for the conservation of mountain species.
避免体温过高需要恒温动物付出相当大的代谢成本。在温暖的条件下，恒温动物可能会为了寻找更凉爽的区域而减少食物摄入，以避免热应激并最大限度地保持能量平衡，因此这种成本会增加。为了减轻热应激，恒温动物可能需要采取影响空间利用和觅食行为的策略，这对于了解和预测气候变化的影响以及为保护行动提供信息非常重要。我们使用资源选择模型来研究高山野山羊（Capra ibex）对热应激的行为反应，高山野山羊是一种适应寒冷的恒温动物，特别容易过热。野山羊通过选择基于最高日温度的空间来避免热应激，而不是每小时移动以“冲浪热浪”，这最大限度地降低了移动成本，但妨碍了最佳觅食。通过将这些发现与新的气候预测相结合，我们预测，气温上升将迫使山地有蹄类动物向上迁移，并因承载能力降低而过度拥挤在热避难所。我们的方法有助于确定保护山地物种的优先区域。
