Upwelling and eddies affect connectivity among local populations of the goldeye rockfish,Sebastes thompsoni(Pisces, Scorpaenoidei)

Abstract

AbstratThe goldeye rockfish, Sebastes thompsoni, commercial rockfish catch in the Northwest Pacific Ocean, may influence its population structure. To clarify the population genetic structure of Korean S. thompsoni and its degree of hybridization with the most close species, Sebastes joyneri, we analyzed a mitochondrial (mt) DNA control region and eleven polymorphic microsatellite (ms) loci. S. joyneri individuals were clearly distinguished from S. thompsoni by the mtDNA control region and ms loci results, with single interspecific hybridization between two species suggesting no impact on genetic structure of S. thompsoni. Analysis of mtDNA revealed no population structure within S. thompsoni, suggesting the survival of a single population in southern refugia during the glacial period. The ms loci results, in contrast, showed two genetically distinct clusters within S. thompsoni: One was predominant throughout Korean coasts (from the Yellow Sea, via the Korea Strait to the East Sea); the other was predominant at Dokdo Island in the East Sea; and both occurred in similar ratios at Wangdolcho Reef in the East Sea. A possible factor that restricts gene flow between Korean coastal and offshore populations in the East Sea may be related to the complex oceanic current patterns such as eddies and upwelling, which represent impermeable barriers to population connectivity for this species. Our findings highlight that these two populations might be representative of two separate stock within Korean waters and maintain their geographically related genetic structure.

MtDNA-Based Phylogeography of the Red Alga Agarophyton vermiculophyllum (Gigartinales, Rhodophyta) in the Native Northwest Pacific

“…The central Japan-Pacific coast is characterized by the convergence of the cold Oyashio Current and the warm Kuroshio Current (Figure 1). The interplaying current systems, especially the coastal upwelling, can create distinct physical barrier for genetic exchange, particularly for the passive drifting spores and fragments of A. vermiculophyllum (Yu and Kim, 2018). However, the current and upwelling regime may not have served as the primary vicariance separating lineages 1 and 2 because they are only distantly related.…”

Natural mega disturbances drive spatial and temporal changes in diversity and genetic structure on the toadfish Aphos porosus

“…Natural strong disturbances, including hypoxic-upwelling events, earthquakes, and tsunamis, have resulted in mass mortality among marine populations, increasing drift strength and affecting gene flow, causing the loss of genetic diversity as well as changes in population structure 2 – 4 , 10 , 44 . Understanding the relationship between demographic and genetic changes over time is of critical importance to predict resistance in at-risk populations, particularly in spatially structured populations (i.e.…”

“…Several studies suggest that upwelling process, independent from hypoxic stressing conditions generated in short-time periods, can affect connectivity among local marine populations. Upwelling acts as a barrier to dispersal, resulting in growth of in genetic structure 7 – 9 , as observed in the Sebastes thompsoni 10 fish, for instance. On the other hand, earthquakes and tsunamis can promote gene flow among populations, increasing local genetic diversity, and reducing genetic population structure.…”

Connectivity Analysis Applied to Mesoscale Eddies in the Western Mediterranean Basin

“…Eddies also have an impact on the biological activity and fishing stocks distribution all around the global ocean [73][74][75][76][77]. They also represent a unique and powerful system for larvae and juvenile dispersal during their early pelagic life stages [78][79][80] providing significant opportunities/limitations for habitat expansion, maintenance of sustainable population sizes, and the exchange of genetic material between geographically distant populations. Additionally, recent studies assessed that the Mediterranean Sea is very vulnerable to possible accumulation of floating litter e.g., [81][82][83], and that a general tendency of floating matter to collect in the southern portion of the WMED basin is realistic [19].…”