Neutral and adaptive loci reveal fine‐scale population structure in Eleginops maclovinus from north Patagonia

Abstract

Patagonia is an understudied area, especially when it comes to population genomic studies with relevance to fishery management. However, the dynamic and heterogeneous landscape in this area can harbor an important but cryptic genetic population structure. Once such information is revealed, it can be integrated into the management of infrequently investigated species. Eleginops maclovinus is a protandrous hermaphrodite species with economic importance for local communities that are currently managed as a single genetic unit. In this study, we sampled five locations distributed across a salinity cline from Northern Patagonia to investigate the genetic population structure of E . maclovinus . We used restriction site‐associated DNA (RAD) sequencing and outlier tests to obtain neutral and adaptive loci, using F ST and GEA approaches. We identified a spatial pattern of structuration with gene flow and spatial selection by environmental association. Neutral and adaptive loci showed two and three genetic groups, respectively. The effective population sizes estimated ranged from 572 (Chepu) to 14,454 (Chaitén) and were influenced more by locality than by salinity cline. We found loci putatively associated with salinity suggesting that salinity may act as a selective driver in E . maclovinus populations. These results suggest a complex interaction between genetic drift, gene flow, and natural selection in this area. Our findings also suggest several evolutionary significant units in this area, and the information should be integrated into the management of this species. We discussed the significance of these results for fishery management and suggest future directions to improve our understanding of how E . maclovinus has adapted to the dynamic waters of Northern Patagonia.

Population Genetic Structure of Marine Fishes

“…The dynamic and heterogeneous landscape in Patagonia, can harbor an important Population Genetic Structure of Marine Fishes DOI: http://dx.doi.org/10.5772/intechopen.112694 but cryptic genetic population structure using restriction site-associated DNA (RAD) sequencing. In five locations sampled, distributed across a salinity cline from Northern Patagonia, Canales et al [69] identified a spatial structuration with gene flow and spatial selection by environmental association. Neutral loci gave two genetic group meanwhile adaptive loci gave three genetic groups.…”

Population genomics of coastal Pacific Hake

“…Genomic techniques, which generate thousands to millions of polymorphic loci, have increased power for detecting population structure and signals of adaptation, making them particularly attractive for application to marine systems (Waples and Gaggiotti 2006;Bernatchez et al 2017). Indeed, there is a growing number of examples in which genomic approaches detected population structure in marine or fishery species that previously went undetected by using traditional genetic techniques (Nielsen et al 2012;Gaither et al 2015;Ackiss et al 2020;Glass et al 2021;Canales-Aguirre et al 2022;Longo et al 2022), some of which include the identification of genomic structural variants associated with adaptive variation (Benestan et al 2016;Berg et al 2016;Barth et al 2017;Longo et al 2020). Despite these promising results, most assessments for species that are harvested in commercial fisheries do not include genomic insights on stock structure (Bernatchez et al 2017).…”

“…2021; Canales‐Aguirre et al. 2022; Longo et al. 2022), some of which include the identification of genomic structural variants associated with adaptive variation (Benestan et al.…”