Climate change is altering the physiology and phenology of an arctic hibernator

Climate warming is rapid in the Arctic, yet impacts to biological systems are unclear because few long-term studies linking biophysiological processes with environmental conditions exist for this data-poor region. In our study spanning 25 years in the Alaskan Arctic, we demonstrate that climate change is affecting the timing of freeze-thaw cycles in the active layer of permafrost soils and altering the physiology of arctic ground squirrels (Urocitellus parryii). Soil freeze has been delayed and, in response, arctic ground squirrels have delayed when they up-regulate heat production during torpor to prevent freezing. Further, the termination of hibernation in spring has advanced 4 days per decade in females but not males. Continued warming and phenological shifts will alter hibernation energetics, change the seasonal availability of this important prey species, and potentially disrupt intraspecific interactions.

北极地区气候变暖速率极快，但目前对其生态系统的影响仍不明确——这一数据匮乏区域中，将生物生理过程与环境条件相关联的长期研究极少。本研究在阿拉斯加北极地区开展了长达25年的观测，结果表明气候变化正在改变永久冻土土壤活动层的冻融循环时序，并影响北极地松鼠（Urocitellus parryii）的生理状态。土壤冻结时间已出现延后，北极地松鼠也随之推迟了在蛰伏期上调产热以抵御低温的时间节点。此外，雌性个体的春季冬眠终止时间每十年提前4天，而雄性个体未出现此变化。若未来持续变暖且物候发生改变，将进一步改变冬眠能量代谢，影响这一重要猎物物种的季节可获得性，并可能破坏种内相互作用。