Data from: Seasonal variation in behavioral thermoregulation and predator avoidance in a small mammal

Understanding behavioral responses of animals to the thermal environment is of increasing importance under changing climate regimes. Thermoregulatory behaviors, such as exploitation of thermal refugia or temporal partitioning of activity, can buffer organisms against hot and cold thermal extremes but may conflict with other life history needs. Our objective was to evaluate strategies for behavioral thermoregulation by a small-bodied endotherm to test hypotheses about tradeoffs between thermal and security needs across seasons. We quantified the influence of both thermal and security properties of habitat on selection of rest sites by pygmy rabbits (Brachylagus idahoensis), and we identified environmental and endogenous factors affecting levels of activity during summer and winter. Behavioral strategies varied seasonally in response to both thermal challenges and risk of predation. During summer, rabbits selected rest sites with high concealment and low shortwave radiation, but activity levels were independent of ambient temperature. During winter, however, security, but not thermal properties, influenced selection of rest sites, and activity was positively correlated with ambient temperature during the most thermally stressful periods of the day (dawn, dusk, and night). The types of nuanced behavioral plasticity that we documented in response to the thermal environment is likely to be overlooked in evaluations of species tolerance to changing climates. Understanding the potential for behavior to buffer individuals as well as the limits of behavior to shield populations from consequences of climate change is critical for effective conservation of vulnerable species.在气候动态变化的背景下，探究动物对热环境的行为响应愈发重要。体温调节行为——例如利用热庇护所或对活动进行时间分区——能够帮助生物体抵御极端高温与低温，但也可能与其他生活史需求产生冲突。本研究旨在评估小型恒温动物的体温调节行为策略，以检验跨季节内热需求与安全需求之间权衡关系的相关假说。我们以侏兔（*Brachylagus idahoensis*）为研究对象，量化分析了生境的热属性与安全属性对其休憩位点选择的影响，并明确了影响夏冬两季活动水平的环境与内源因素。其体温调节行为策略会随季节变化，以应对热胁迫与捕食风险。夏季时，侏兔会选择隐蔽性高、短波辐射低的休憩位点，但其活动水平与环境温度无关。但在冬季，影响休憩位点选择的仅为安全属性而非热属性；且在每日热胁迫最显著的时段（黎明、黄昏与夜间），其活动水平与环境温度呈正相关。我们观测到的这类针对热环境的精细化行为可塑性，在评估物种对气候变化的耐受性时很可能被忽视。明确行为可为个体提供缓冲的潜力，以及行为保护种群免受气候变化影响的极限，对脆弱物种的有效保护至关重要。