Shark conservation genetics

Elasmobranchs are of global conservation concern with around 25% of all species considered threatened with extinction. Population declines are largely due to overexploitation both through targeted fisheries and as bycatch. Despite increasing awareness of these issues, significant knowledge gaps remain about their basic biology, diversity and distribution which has resulted in limited fisheries regulation and conservation management. We are working on several projects that will fill these knowledge gaps and help provide evidence-based recommendations to prevent overexploitation.

Sri Lankan and Indian Ocean elasmobranch fisheries

The Indian Ocean is a global hotspot for shark and ray diversity. Unsurprisingly, it is also home to some of the highest levels of fishing activity in the world, posing a severe threat to the survival of these vulnerable species. We are working closely with Blue Resources Trust to carry out population genetic assessments of some of the most heavily targeted CITES-listed elasmobranchs the Indian Ocean. This information will help underpin the development of national and regional policies for conserving shark populations. Alongside this, we are also helping to build capacity in Sri Lanka to monitor and regulate the elasmobranch trade and therefore minimise illegal and unsustainable fishing activities.

Please contact Emily Humble for more information.

Atlantic elasmobranch genetics: Oceanic islands as essential habitat for migratory elasmobranchs

Some of the most vulnerable sharks and rays are migratory species that depend on the restricted coastal habitats of oceanic islands. However, the exact role of these habitats for breeding, feeding and growth in elasmobranch populations is virtually unknown. This is the case for the Azores, the most isolated archipelago in the North East Atlantic and likely an ‘Essential Fish Habitat’ for sharks and rays. To elucidate the role of the Azores and other coastal habitats in the wider Atlantic for elasmobranch ecology and conservation, we are undertaking a population genetic study of three cosmopolitan and threatened species with contrasting life histories and behaviour: tope shark (Galeorhinus galeus), smooth hammerhead shark (Sphyrna zygaena) and chilean devil ray (Mobula tarapacana). We are using a combination of SNPs and mitochondrial DNA to assess population connectivity at multiple geographic scales and expect our results to support the development of sound management and conservation actions. This work is being carried out in collaboration with Pedro Afonso at the University of the Azores.

Please contact Ana Filipa Sobral for further information.