Data from: Adult sex ratio and operational sex ratio exhibit different temporal dynamics in the wild

Adult sex ratio (ASR, the proportion of adult males in the adult population) and operational sex ratio (OSR, the proportion of sexually active males in the mating pool) are fundamental properties of breeding populations and they are often linked to mating systems and sexual selection. However, ASR and OSR emerge via different routes in a population and may exhibit different temporal patterns. Here, we use data from a well-monitored polygamous snowy plover Charadrius nivosus population sampled over 3 consecutive breeding seasons to investigate whether temporal changes in ASR relate to changes in OSR. We found that snowy plovers exhibited male-biased ASR and OSR. Consistent with theoretical expectations, OSR was more variable than ASR. However, there was no consistent relationship between OSR and ASR: in only 1 of the 3 study years we found a weak positive relationship (r = 0.22). The lack of association was corroborated by time series analyses and sensitivity tests. Our work therefore suggests that ASR and OSR exhibit different temporal patterns in a polygamous population, and we call for further theoretical and empirical studies that analyze their relationship across a range of different breeding systems.成体性比（Adult sex ratio, ASR，即成年种群中成年雄性的占比）与操作性别比（operational sex ratio, OSR，即交配池中性活跃雄性的占比）是繁殖种群的核心属性，二者常与交配系统及性选择紧密关联。然而，成体性比与操作性别比在种群中通过不同路径形成，可能呈现出不同的时间动态模式。本研究依托连续3个繁殖季对一处监测完备的多配制雪鸻（Charadrius nivosus）种群的采样数据，探究成体性比的时间变化是否与操作性别比的变化相关。研究结果显示，雪鸻种群的成体性比与操作性别比均偏向雄性偏倚；与理论预期一致，操作性别比的波动幅度大于成体性比。但二者之间并未呈现稳定的关联：仅在3个研究年份中的1个年份，二者存在微弱的正相关关系（相关系数r=0.22）。时间序列分析与敏感性检验进一步证实了二者无显著关联。综上，本研究表明在多配制种群中，成体性比与操作性别比呈现出不同的时间动态模式，我们呼吁开展更多跨不同繁殖系统的理论与实证研究，以深入剖析二者的关联关系。