Data from: How stock of origin affects performance of individuals across a meta-ecosystem: an example from Sockeye salmon

Connectivity among diverse habitats can buffer populations from adverse environmental conditions, influence the functioning of meta-ecosystems, and ultimately affect the reliability of ecosystem services. This stabilizing effect on populations is proposed to derive from complementarity in growth and survival conditions experienced by individuals in the different habitats that comprise meta-ecosystems. Here we use the fine scale differentiation of salmon populations between diverse lake habitats to assess how rearing habitat and stock of origin affect the body condition of juvenile sockeye salmon. We use genetic markers (single nucleotide polymorphisms) to assign individuals of unknown origin to stock group and in turn characterize ecologically relevant attributes across habitats and stocks. Our analyses show that body condition of juvenile salmon is related to the productivity of alternative habitats across the watershed, irrespective of their stock of origin. Emigrants and residents with genetic origins in the high productivity lake were also differentiated by their body condition, poor and high respectively. These emigrants represented a substantial proportion of juvenile sockeye salmon rearing in the lower productivity lake habitat. Despite emigrants originating from the more productive lake, they did not differ in body condition from the individuals spawned in the lower productivity, recipient habitat. Genetic tools allowed us to assess the performance of different stocks groups across the diverse habitats comprising their meta-ecosystem. The ability to characterize the ecological consequences of meta-ecosystem connectivity can help develop strategies to protect and restore ecosystems and the services they provide to humans.

不同生境间的连通性可缓冲种群面临的不利环境胁迫，影响复合生态系统（meta-ecosystems）的整体功能，并最终改变生态系统服务的可靠性。这种对种群的稳定效应，被认为源于构成复合生态系统的不同生境中，个体所经历的生长与存活条件的互补性。本研究借助不同湖泊生境间鲑鱼种群的精细尺度分化特征，探究育幼生境与原产地种群（stock of origin）如何影响幼年红大麻哈鱼（juvenile sockeye salmon）的身体状况。我们采用遗传标记（genetic markers，即单核苷酸多态性（single nucleotide polymorphisms））对未知来源的个体进行种群组归属判定，借此表征不同生境与种群间的生态学相关属性。分析结果表明，幼年鲑鱼的身体状况与流域内不同备选生境的生产力密切相关，而与它们所属的原产地种群无关。具有高生产力湖泊遗传起源的洄游个体与定居个体，其身体状况同样存在分化：前者身体状况欠佳，后者则处于较佳水平。这类洄游个体在低生产力湖泊生境中的幼年红大麻哈鱼种群中占据相当大的比例。尽管这些洄游个体源自生产力更高的湖泊，但它们与在低生产力接收生境中产卵的个体相比，身体状况并无显著差异。借助遗传工具，我们得以评估构成复合生态系统的不同生境中，不同种群组的生存表现。明确复合生态系统连通性所带来的生态效应的能力，有助于制定保护与修复生态系统及其为人类提供的服务的相关策略。