Data from: Outlier loci detect intraspecific biodiversity amongst spring and autumn spawning herring across local scales

Herring, Clupea harengus, is one of the ecologically and commercially most important species in European northern seas, where two distinct ecotypes have been described based on spawning time; spring and autumn. To date, it is unknown if these spring and autumn spawning herring constitute genetically distinct units. We assessed levels of genetic divergence between spring and autumn spawning herring in the Baltic Sea using two types of DNA markers, microsatellites and Single Nucleotide Polymorphisms, and compared the results with data for autumn spawning North Sea herring. Temporally replicated analyses reveal clear genetic differences between ecotypes and hence support reproductive isolation. Loci showing non-neutral behaviour, so-called outlier loci, show convergence between autumn spawning herring from demographically disjoint populations, potentially reflecting selective processes associated with autumn spawning ecotypes. The abundance and exploitation of the two ecotypes have varied strongly over space and time in the Baltic Sea, where autumn spawners have faced strong depression for decades. The results therefore have practical implications by highlighting the need for specific management of these co-occurring ecotypes to meet requirements for sustainable exploitation and ensure optimal livelihood for coastal communities.

大西洋鲱（Clupea harengus）是北欧海域生态与商业价值最为重要的物种之一，依据产卵时间可将该海域的鲱鱼划分为两个截然不同的生态型：春季产卵型与秋季产卵型。截至目前，这两类产卵型鲱鱼是否属于遗传分化的独立种群仍未明确。本研究以波罗的海海域的春季与秋季产卵型鲱鱼为研究对象，采用微卫星（microsatellites）与单核苷酸多态性（Single Nucleotide Polymorphisms, SNP）两类DNA分子标记，分析二者的遗传分化水平，并将结果与北海秋季产卵型鲱鱼的相关数据进行对比。通过时序重复采样分析，研究团队发现两类生态型间存在显著遗传分化，由此支持二者存在生殖隔离的推论。表现出非中性演化特征的基因座（outlier loci，即离群位点）在彼此隔离的秋季产卵型鲱鱼种群间呈现趋同特征，这一现象可能反映了与秋季产卵生态型相关的选择作用过程。波罗的海海域两类生态型鲱鱼的资源量与开发强度在空间与时间维度均存在显著波动，其中秋季产卵型鲱鱼的种群数量已持续数十年处于严重衰退状态。因此，本研究结果具有重要的实践指导意义：研究凸显了对这两类同域分布的生态型开展针对性管理的必要性，以满足渔业资源可持续开发的需求，并保障沿海社区的最优生计。