Genomic analysis of NE Atlantic sardine () reveals reduced variation in a recently established North Sea population and directs reconsideration of management units.

The European sardine () is under intense fishing pressure and exhibits distributional/abundance shifts linked to environmental change. The current understanding of population demographics needed for sustainable management is uncertain due to concerns that previous genetic studies lacked resolution and limited sampling of sardine north of the Bay of Biscay. To address these issues, we performed mtDNA sequencing and genome wide SNP analysis of samples collected across the Bay of Biscay, Celtic Sea, English Channel and North Sea.

Genetic analysis of reveals high gene flow in the South-West Indian Ocean.

(Gray, 1849), abundant in the South-West Indian Ocean (SWIO), constitutes a vital resource for both subsistence and commercial fisheries. However, despite this socioeconomic importance, and recent indications of overfishing, little is known about the population structure of in the region. To inform sustainable management strategies, this study assessed the spatio-temporal population structure and genetic variability of at 20 sites in the SWIO (Kenya, Tanzania, Mozambique, Madagascar, Mauritius, Rodrigues, and the Seychelle Islands) by complementary analysis of mitochondrial DNA (mtDNA) noncoding region (NCR) sequences and microsatellite markers.