Data from: Does catch and release affect the mating system and individual reproductive success of wild Atlantic salmon (Salmo salar L.)?

In this study, we documented the breeding system of a wild population of Atlantic salmon (Salmo salar L.) by genetically sampling every returning adult and assessed the determinants of individual fitness. We then quantified the impacts of catch and release (C&R) on mating and reproductive success. Both sexes showed high variance in individual reproductive success, and the estimated standardized variance was higher for males (2.86) than for females (0.73). We found a weak positive relationship between body size and fitness and observed that fitness was positively correlated with the number of mates, especially in males. Mature male parr sired 44% of the analysed offspring. The impact of C&R on the number of offspring was size dependent, as the reproductive success of larger fish was more impaired than smaller ones. Also, there was an interactive negative effect of water temperature and air exposure time on reproductive success of C&R salmon. This study improves our understanding of the complex reproductive biology of the Atlantic salmon and is the first to investigate the impact of C&R on reproductive success. Our study expands the management toolbox of appropriate C&R practices that promote conservation of salmon populations and limit negative impacts on mating and reproductive success.本研究通过对每尾洄游成年大西洋鲑（Salmo salar L.）个体开展遗传采样，厘清了该野生种群的繁殖系统，并解析了个体适合度的决定因素。随后，本研究量化了捕获放流（catch and release, C&R）对鲑鱼交配成功率与繁殖成功率的影响。研究结果显示，两性个体的繁殖成功率均表现出较高的变异水平，其中雄性的标准化估计变异值（2.86）显著高于雌性（0.73）。我们发现体型与个体适合度呈弱正相关，且适合度与交配对象数量呈正相关，这一相关性在雄性个体中尤为显著。早熟雄性幼鲑（mature male parr）为本研究分析的44%子代提供了父系来源。捕获放流对子代数量的影响存在体型依赖性：体型较大的个体其繁殖成功率受抑制的程度高于体型较小的个体。此外，水温与空气暴露时长的交互作用对捕获放流鲑鱼的繁殖成功率存在负向影响。本研究深化了学界对大西洋鲑复杂繁殖生物学的认知，且是首个探究捕获放流对繁殖成功率影响的相关研究。本研究拓展了适配的捕获放流实践管理工具库，既能助力鲑鱼种群保护，又可有效降低其对交配与繁殖成功率的负面影响。