A genome-smart approach towards conservation management of threatened elasmobranchs in the Western Indian Ocean

On a global scale, human-induced climate change and the over-exploitation of marine species is placing severe pressure on regional biodiversity and ecosystems. Now more than ever, it is critical to preserve the unique genetic populations adapted to specific environmental niches due to the vulnerability of elasmobranchs (sharks, skates and rays) to global change. Genomic studies provide a means not only to assess the degree of connectivity between marine populations but also to allow the identification of gene regions involved in genomic adaptation by comparing relative differentiation among genome-wide loci. The overall aim of our research is therefore to improve our knowledge on elasmobranchs impacted by fisheries and environmental changes in coastal waters of the Western Indian Ocean. This includes strategies such as 1) to confirm the number of species / validate species distribution ranges; 2) assess neutral genetic variation within species while investigating their adaptive potential and 3) perform Genotype-Environment Association (GEA) analysis in order to identify genomic regions and environmental variables involved in adaptation. Results will be presented using examples of various focal species to demonstrate how these genomic resources provide an opportunity to extend our understanding of not only the genomic mechanisms in these species but also as indicators of their vulnerability. This is also expected to inform management strategies and policy at the national and regional level for conservation of these vulnerable elasmobranch populations.