This project is set up to assess potential genetic discontinuities between different species of Amblyraja skates caught during by-catch activities in order to inform fisheries management. Skates are frequently caught as by-catch during commercial longline fishing operations in the Southern Ocean. Morphological observations of the by-catch suggest that up to three species of Amblyraja skates are caught during these operations: A. georgiana, A. georgiana sp. anon., and A. taaf. We are collaborating in a project led by the British Antarctic Survey aiming to determine if current taxonomic classifications based of morphological characters of the Amblyraja species caught as by-catch do reflect potential genetic discontinuities. A first study using newly developed microsatellite markers and mitochondrial DNA sequences revealed that A. georgiana, A. georgiana sp. anon. and A. taaf do not represent genetically distinct species and that geography (sampling location) is the factor explaining the observed genetic discontinuities. Furthermore, skates collected in South Georgia showed higher genetic variation than those collected in the South Sandwich Islands; therefore, indicating that stocks in the latter geographical areas may be more vulnerable to fishing activities. Further studies will focus on assessing the adaptive potential of the different Antarctic stocks. Please contact Dr Will Goodall-Copestake (British Antarctic Survey) or Dr Sílvia Pérez-Espona for further information. This article was published on 2024-09-02
