Marmot capture history data and growing season length data

Seasonal environmental conditions shape the behavior and life history of virtually all organisms. Climate change is modifying these seasonal environmental conditions, which threatens to disrupt population dynamics. It is conceivable that climatic changes may be beneficial in one season but result in detrimental conditions in another because life-history strategies vary between these time periods. We analyzed the temporal trends in seasonal survival of yellow-bellied marmots (Marmota flaviventer) and explored the environmental drivers using a 40-y dataset from the Colorado Rocky Mountains (USA). Trends in survival revealed divergent seasonal patterns, which were similar across age-classes. Marmot survival declined during winter but generally increased during summer. Interestingly, different environmental factors appeared to drive survival trends across age-classes. Winter survival was largely driven by conditions during the preceding summer and the effect of continued climate change was likely to be mainly negative, whereas the likely outcome of continued climate change on summer survival was generally positive. This study illustrates that seasonal demographic responses need disentangling to accurately forecast the impacts of climate change on animal population dynamics. We were able to impute body mass for each individual twice during each year following their first capture using a similar approach to Ozgul et al. (2010) (for more details on the modeling procedure see SI Appendix within the main paper). Body mass measurements were log-transformed.季节性环境条件塑造了几乎所有生物的行为与生活史策略。气候变化正在改变这类季节性环境条件，进而可能对种群动态造成干扰。由于不同时段的生活史策略存在差异，气候变化可能在某一季节产生益处，却在另一季节带来有害环境，这一设想具备合理性。本研究依托美国科罗拉多落基山脉长达40年的数据集，分析了黄腹旱獭（*Marmota flaviventer*）季节性存活率的时间变化趋势，并探究了其环境驱动因子。存活率的变化呈现出分化的季节模式，且该模式在不同年龄组间保持一致：旱獭冬季存活率呈下降趋势，而夏季存活率则总体上升。值得注意的是，不同年龄组的存活率变化趋势受到各异的环境因子调控。冬季存活率主要受前一夏季的环境条件影响，持续气候变化对冬季存活率的影响大概率以负面为主；与之相对，持续气候变化对夏季存活率的潜在影响总体上呈积极态势。本研究表明，若要精准预测气候变化对动物种群动态的影响，需厘清不同季节的种群统计响应特征。本研究参考Ozgul等（2010）的方法，对首次捕获后的每只个体，每年可估算两次体重；有关建模流程的详细细节，请参见正文中的SI Appendix。体重测量值均经过对数转换处理。