New Zealand’s exploratory fishery for toothfish within the SPRFMO Convention Area: update and future directions

The 2-year programme of exploratory fishing provided for by SPRFMO CMM 4.14 has been successfully completed and new and important biological information has been collected on toothfish outside the CCAMLR convention area. The key findings are that only Antarctic toothfish, Dissostichus mawsoni, were caught, that these were mostly male (~85%), and that most fish were in spawning condition or spent. These surveys provide information on the life history of Antarctic toothfish that is consistent with the current hypothesis on Antarctic toothfish growth and movement, and have provided the some of the first empirical scientific observations of spawning Antarctic toothfish. Information collected during these first two voyages will be shared with CCAMLR and had been used in the stock assessment of Antarctic toothfish in the Ross Sea region. Over the coming months, New Zealand will screen video footage and analyse all data collected in more detail than the timing of the voyages has allowed so far. In addition, to maximise the value of future data collection for both organisations’ understanding of the distribution, dynamics and status of stocks of Antarctic toothfish, New Zealand will also assess the optimum quantity and nature of data required to enable the development of a spatially-explicit integrated stock assessment model of Antarctic toothfish in the region. It is anticipated that this model, targeted for completion in 2021, will include those components of the Antarctic toothfish stock residing in the SPRFMO Area as well as in the CCAMLR Area. At this stage, it is intended that a comprehensive proposal for the future of the exploratory fishery will be presented to SPRFMO Scientific Committee in 2018.