Population genomics and environmental adaptation in the sea scallop, Placopecten magellanicus, detected using RAD-seq derived SNPs and experimental larval rearing

Abstract

Understanding the scale of connectivity and adaptation among marine populations can inform fisheries conservation and management. We used a combination of advanced genomic techniques and experimental methods to determine the scale of connectivity and adaptation in the sea scallop, Placopecten magellanicus. Restriction-site Associated DNA sequencing genotyped 7163 SNPs in 245 individuals across 12 populations in the Northwest Atlantic. Subsequent analysis of these data identified a strong separation between populations north and south of Nova Scotia and identified an association between population structure and the coldest temperatures experienced by scallop populations. Common garden experiments on a northern and southern populations found that larvae from the north grew more quickly overall, potentially an adaptive strategy to the northern winter. These observations contribute to growing evidence of fine-scale population structure and adaptation in marine systems and support the hypothesis that a combination of limited dispersal and adaptive differentiation drives sea scallop population structure.