Climate-induced fluctuations in marine fish populations have been raising great scientific concerns. Previous studies generally dedicate to parameterization of climatic, environmental, and biological variability patterns with focuses on their empirical or incompletely mechanistic relationships. Little consideration on physiological characteristics of organisms prevents from exploring mechanisms behind the apparent relationships. Therefore, incorporating physiological information into investigation on climate–environment–biology relationships is essential to understand climate-induced biological variability. Small pelagic fishes play unparalleled roles in the Kuroshio ecosystem and show dramatic fluctuations in response to environmental changes, serving as ideal research targets in studies on climate-induced biological variability. This study focuses on Japanese sardine, chub mackerel, and Japanese anchovy, three key small pelagic fishes in the Kuroshio ecosystem with distinct physiological characteristics, with attempts to incorporate thermal niches into investigations on their responses to climate variability. The recruitment suitable index (RSI) is developed considering both sea surface temperature (SST) and species thermal niche. Results show that the RSI significantly increase explanations on variations in resource abundance indices of the three key small pelagic fishes. Responses of small pelagic fishes to climate variability show differences by species and stocks. In addition, variations in the Siberian High pressure system and Atlantic Multidecadal Oscillation contribute highly to variations in resource abundance indices through affecting the SST and further the RSI. This study demonstrates importance of physiological information for understanding climate-induced biological variability and effectiveness of combining thermal niches with the investigation on mechanistic climate–environment–biology relationships, which should be extensively considered in the future studies.

中文翻译：

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结合热生态位有助于了解黑潮生态系统中小型中上层鱼类的气候引起的生物变异性

气候引起的海洋鱼类种群波动引起了极大的科学关注。以前的研究通常致力于气候、环境和生物变异模式的参数化，重点关注它们的经验或不完全机械关系。很少考虑生物体的生理特征会阻止探索明显关系背后的机制。因此，将生理信息纳入气候-环境-生物学关系的调查对于了解气候引起的生物变异至关重要。小型中上层鱼类在黑潮生态系统中发挥着无与伦比的作用，并在响应环境变化时表现出巨大的波动，是气候引起的生物变异研究的理想研究对象。本研究重点关注日本沙丁鱼、鲭鱼和日本鳀鱼，这是黑潮生态系统中具有不同生理特征的三种重要的小型中上层鱼类，并试图将热生态位纳入其对气候变化响应的调查中。考虑海面温度（SST）和物种热生态位，开发适合招募指数（RSI）。结果表明，RSI显着增加了对三种主要小型中上层鱼类资源丰度指数变化的解释。小型中上层鱼类对气候变化的反应显示出物种和种群的差异。此外，西伯利亚高压系统和大西洋多年代际涛动的变化通过影响SST和进一步的RSI，对资源丰度指数的变化做出了很大贡献。