Population genomic analysis of the blue crab Callinectes sapidus using genotyping-by-sequencing

Previous genetic studies of the blue crab Callinectes sapidus along the U.S. Atlantic and Gulf coasts have reported weak or temporally variable spatial structure, suggesting high gene flow among distant populations possibly facilitated by long-distance larval dispersal or other features of blue crab life history. The use of relatively few genetic markers, however, may have limited power to detect subtle but significant structure that could inform fisheries management. In this study, the potential for genome-scale datasets to uncover subtle patterns of population structure in the blue crab was examined using a high-throughput genotyping approach (genotyping-by-sequencing) that generated data for more than 9,600 single nucleotide polymorphisms (SNPs) in crabs from three populations: Panama City Beach, FL, Agawam River, MA, and Porto Alegre, Brazil. Principle components analyses among the three populations revealed very distinct clustering of the Brazilian samples from U.S. populations, li...