Assessment of the toothfish (Dissostichus eleginoides) resource in the Prince Edward Islands vicinity to include data from 1997 to 2017

Abstract

The assessment of the Prince Edward Islands (PEI) toothfish (Dissostichus eleginoides) resource carried out by Brandão and Butterworth (2017) is updated to take further data now available for 2017 into account. This update also incorporates tag-recapture data and a new basis to estimate the extent of cetacean depredation. For the Base case and many of the assessment sensitivities, the resource is estimated to be at a depletion (in relation to its average pre-exploitation level in terms of spawning biomass) in the 36-42% range. If the model is forced to fit the trotline CPUE indices and the tag-recapture data as well, the estimated average pre-exploitation level in terms of spawning biomass is in the range of 12-26%, but this requires an assumption of very high levels of tag loss.