Population genetic data for Atlantic meagre, <em>Argyrosomus regius</em>

Information on population structure and connectivity of targeted species is key for proper implementation of spatial conservation measures. We used a combination of genomics, biophysical modelling, and biotelemetry to infer the population structure and connectivity of Atlantic meagre, an important fisheries resource throughout its distribution. Genetic samples from previously identified Atlantic spawning locations (Gironde, Tejo, Guadalquivir, Banc D’Arguin) and two additional regions (Algarve and Senegal) were analysed using genome-wide SNP-genotyping and mitochondrial DNA analyses. Biophysical models were conducted to investigate larval dispersal and connectivity from the known Atlantic spawning locations. Additionally, thirteen fish were double-tagged with biotelemetry transmitters off the Algarve (Portugal) to assess movement patterns and connectivity of adult individuals. This multidisciplinary approach provided a robust overview of meagre population structure and connectivity in the Atlantic. Nuclear SNP-genotyping showed a clear differentiation between the European and African populations, with significant isolation of the few known Atlantic spawning sites. The limited level of connectivity between these subpopulations is potentially driven by adults, capable of wide-ranging movements and connecting sites 500 km apart, as evidenced by tagging studies, whilst larval dispersal inferred by modelling is much more limited (average of 52 km; 95 % of connectivity events up to 174 km). Our results show sufficient evidence of population structure, particularly between Africa and Europe but also within Europe, for the meagre to be managed as separate stocks. Additionally, considering the low degree of larvae connectivity, the implementation of marine protected areas in key spawning sites could be crucial towards species sustainability. Tissue samples were collected from six sites along the eastern Atlantic coastline, from France south to Senegal. The data was generated through DARTseq analysis, a reduced representation genotyping-by-sequencing approach that generates SNP genotype data at a series of loci distributed throughout the genome. Raw data have been filtered by SNP genotype call rate (> 95 %) and SNP heterozygosity (> 0.05). The filtered dataset is composed of 1534 SNP loci and 87 individual fish. The data is a .csv file and may be opened in Excel or any text editor. # Population genetic data for Atlantic meagre, *Argyrosomus regius* Dataset DOI: [10.5061/dryad.08kprr56q](10.5061/dryad.08kprr56q) ## Description of the data and file structure Population genetic data for Atlantic meagre, *Argyrosomus regius* * Abecasis_et_al_Meagre_SNP_data_upload.csv The data are SNP genotypes derived from DARTseq genotyping-by-sequencing analysis of individual fish (meagre) collected from six sample sites along the western Atlantic coast. The data consist of 1534 SNPs and 87 individuals. Data are provided as a genotype matrix containing 1534 SNP loci in 2-column format (3068 columns), with 87 rows of individual genotype data Data are provided as a .csv file as follows: Row 1: Number of SNP loci, total number of samples, number of localities, number of samples per locality Row 2: Data type, Locality names Row 3: Data column headers (Sample, Pop (=Locality), Locus names (2 columns per locus) Row 4 (and onwards): Data (Sample name, Locality, Genotype (2 column) 2-column Genotype coding: Homozygote Allele 1: 1,1 Homozygote Allele 2: 2,2 Heterozygote: 1,2 Missing data: 0 \## Sharing/Access information No relevant information \## Code/Software No relevant information ## Code/software Text editor or excel