title: Outlier Loci Detect Intraspecific Biodiversity amongst Spring and Autumn Spawning Herring across Local Scales.
abstract: Herring, Clupea harengus, is one of the ecologically and commercially most important species in European northern seas, where two distinct ecotypes have been described based on spawning time; spring and autumn. To date, it is unknown if these spring and autumn spawning herring constitute genetically distinct units. We assessed levels of genetic divergence between spring and autumn spawning herring in the Baltic Sea using two types of DNA markers, microsatellites and Single Nucleotide Polymorphisms, and compared the results with data for autumn spawning North Sea herring. Temporally replicated analyses reveal clear genetic differences between ecotypes and hence support reproductive isolation. Loci showing non-neutral behaviour, so-called outlier loci, show convergence between autumn spawning herring from demographically disjoint populations, potentially reflecting selective processes associated with autumn spawning ecotypes. The abundance and exploitation of the two ecotypes have varied strongly over space and time in the Baltic Sea, where autumn spawners have faced strong depression for decades. The results therefore have practical implications by highlighting the need for specific management of these co-occurring ecotypes to meet requirements for sustainable exploitation and ensure optimal livelihood for coastal communities.
authors.affiliation: Technical University of Denmark, National Institute of Aquatic Resources, Charlottenlund, Denmark.
authors.forename: Dorte
authors.initials: D
authors.lastname: Bekkevold
authors.affiliation: Estonian University of Life Sciences, Institute of Veterinary Medicine and Animal Sciences, Department of Aquaculture, Tartu, Estonia.
authors.forename: Riho
authors.initials: R
authors.lastname: Gross
authors.affiliation: University of Tartu, Estonian Marine Institute, Pärnu, Estonia.
authors.forename: Timo
authors.initials: T
authors.lastname: Arula
authors.affiliation: Institute for Global Food Security, Queen's University Belfast, Belfast, United Kingdom.
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Helyar
authors.affiliation: University of Tartu, Estonian Marine Institute, Pärnu, Estonia.
authors.forename: Henn
authors.initials: H
authors.lastname: Ojaveer
mesh_terms: D000818:Animals; D044822:Biodiversity; D005399:Fishes / Q000235:genetics* / Q000254:growth & development; D040961:Genetic Drift; D014644:Genetic Variation / Q000235:genetics*; D018895:Microsatellite Repeats; D012621:Seasons