Risk assessment for the Antarctic starry skate (Amblyraja georgiana) in the Ross Sea

The Scientific Committee identified skates (along with macrourids) as “priority bycatch taxa for which assessments of status are required”. Catch data from the Ross Sea region show that most (~90%) of the skate catch consists of Amblyraja georgiana and that this species is the only one with enough mark-recapture data to estimate local biomass. We present methods for updating biomass estimates and exploitation rates consistent with the CCAMLR decision rules for A. georgiana in the Ross Sea. We reprise the risk assessment methodology, summarise the data available for this update, and describe sensitivity estimates to input parameters to account for model uncertainties. Specifically, we have provided a range of possibilities for biomass and exploitation estimates, but model uncertainties still exist, particularly around post-release mortality. We welcome feedback on our methodology and sensitivities from WG-SAM because we plan to update the risk assessment for starry skate for WG-FSA-2023. We note that the following would reduce model uncertainties: (1) the planned year of skate tagging commencing in the 2027/28 season; (2) continued recording of skate injury condition at recapture or release if tagging occurs, and (3) research to improve post-release mortality estimates.