Large and fine scale population structure in European hake (Merluccius merluccius) in the Northeast Atlantic

• Published in: ICES Journal of Marine Science
• Main Authors: Westgaard, Jon-Ivar, Staby, Arved, Godiksen, Jane Aanestad, Geffen, Audrey J., Svensson, Anders, Charrier, Grégory, Svedang, Henrik, Andre, Carl
• Other Authors: Institute of Marine Research Bergen (IMR), University of Bergen (UiB), Department of Aquatic Resources, Swedish University of Agricultural Sciences (SLU), Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Marine Sciences Gothenburg, University of Gothenburg (GU)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2017
• Subjects: ACL; cod gadus-morhua; sea; climate-change; connectivity; markers; skagerrak; demersal; genetic differentiation; genetic variability; Kattegat; loci; marine fishes; North sea; Norwegian sea; single nucleotide polymorphism; spatial structure; stock structure; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Hake; Norway; Norwegian Sea; Gadus morhua; Northeast Atlantic
• Online Access: https://hal.archives-ouvertes.fr/hal-02613240; https://doi.org/10.1093/icesjms/fsw249

WOS:000404450700007 Recently, there have been reports of increased abundance and landings of European hake in the northern part of the species range. Biological studies are however scarce and information about finer scale population structure important for stock assessments and fishery management is largely lacking. Here, we report on a population genetic study using neutral and outlier SNP loci assessing population structure in hake in the north-eastern parts of its range in the Atlantic. Hake samples from localities along the west coast of Norway, the Kattegat, the northern North Sea, and one locality in the Bay of Biscay were analysed using 53 SNPs, six of which were outliers potentially influenced by natural selection. We detected small-scale structure among northern samples, all of which were also distinct from Bay of Biscay hake, with the exception of a few individuals from the North Sea and the coast of Norway who clustered genetically together with Bay of Biscay hake. Our findings suggest that the present management unit of a single northern stock of hake is not biologically correct, and that there is more detail in the fine-scale population structure indicating that independent population dynamics could be expected in response to fishing patterns or changing environmental conditions.