Updated biological parameters of Antarctic Toothfish (Dissostichus mawsoni) at Subarea 48.6 with experimental correction of age datasets

This report updated biological parameters to achieve milestones “1.2. developing ISA models” and ”2.2 Updating Age-Length Key” at Subarea 48.6 (Osawa et al., 2021a). This update includes correction of age estimation of Japanese data using von Bertalanffy growth curve equation derived by Ross Sea female data and Spanish fishery sex-combined data in area 48.6. Age correction method developed in this document is a good start point to fix age error issue at subarea 48.6, however, we may need more analysis about age data. This report recommends (i) Develop consistent method to determine age of Antarctic Toothfish by counting rings of otolith in next CCAMLR Ageing Determination Workshop, (ii) Identify criteria of false ring by International scientists through the workshop.