22nd Regular Session of the Scientific Committee

SC22 will review the proposed estimation method for bigeye tuna, including its structure, assumptions, and performance within the MSE framework, and assess its ability to provide robust and reliable estimates of stock status under key uncertainties represented within the operating model framework. Consistent with BMW01 outcomes, SC22 will also consider the suitability of the proposed EM for application across the alternative spatial configurations and mixed-fishery evaluation framework being developed for the BET MP. SC22 will provide guidance on the suitability of the proposed EM and any required refinements before its application in testing candidate MPs and supporting future MP adoption by the Commission.

• A robust and computationally efficient estimation method (EM) is required to generate reliable stock status signals for management procedures. SC21 reviewed developments in a candidate bigeye estimation method and identified several areas requiring further investigation, including the generation of CPUE indices and the specification of priors for certain estimated productivity parameters.