Data from: Genome-wide SNPs resolve spatiotemporal patterns of connectivity within striped marlin (Kajikia audax), a broadly distributed and highly migratory pelagic species

Genomic methodologies offer unprecedented opportunities for statistically
robust studies of species broadly distributed in environments conducive to
high gene flow, providing valuable information for wildlife conservation
and management. Here, we sequence restriction site-associated DNA to
characterize genome-wide single nucleotide polymorphisms (SNPs) in a
broadly distributed and highly migratory large pelagic fish, striped
marlin (Kajikia audax). Assessment of over 4,000 SNPs resolved
spatiotemporal patterns of genetic connectivity throughout the species
range in the Pacific and, for the first time, Indian oceans.
Individual-based cluster analyses identified six genetically distinct
populations corresponding with the western Indian, eastern Indian, western
South Pacific, and eastern central Pacific oceans, as well as two
populations in the North Pacific Ocean (FST = 0.0137–0.0819). FST outlier
analyses identified a subset of SNPs (n = 59) putatively under the
influence of natural selection, and capable of resolving populations
separated by comparatively high degrees of genetic differentiation.
Temporal collections available for some regions demonstrated the stability
of allele frequencies over three to five generations of striped marlin.
Relative migration rates reflected lower levels of genetic connectivity
between Indian Ocean populations (mR ≤ 0.37) compared with most
populations in the Pacific Ocean (mR ≥ 0.57), and highlight the importance
of the western South Pacific in facilitating gene flow between ocean
basins. Collectively, our results provide novel insights into rangewide
population structure for striped marlin, and highlight substantial
inconsistencies between genetically distinct populations and stocks
currently recognized for fisheries management. More broadly, we
demonstrate that species capable of long-distance dispersal in
environments lacking obvious physical barriers to movement can display
substantial population subdivision that persists over multiple
generations, and that may be facilitated by both neutral and adaptive
processes. Importantly, surveys of genome-wide markers enable inference of
population-level relationships using sample sizes practical for large
pelagic fishes of conservation concern.