The first report of ageing precision, age and growth of Antarctic toothfish (Dissostichus mawsoni) in Subarea 88.2, CCAMLR Convention Area

This study provided the first report on ageing precision, age and growth of Antarctic toothfish (Dissostichus mawsoni) in Subarea 88.2, CCAMLR Convention Area. The APE and ACV values of ageing precision for D. mawsoni were 12.0±6.38 and 15.7±8.17 across 9 counts by three readers, respectively, indicating the growth zone counting is not easy to be identified. Von Bertalanffy growth function parameters indicated Antarctic toothfish ranging in size from 51 to 188 cm TL were relatively slow-growing (k = 0.149), especially in relation to their maximum size (L_ꚙ = 153.5 cm), which is similar to the population in the Subarea 88.1 (Ross Sea region). Our study demonstrated that it’s urgent to improve the ageing technology and accumulate the age data to help undertake the stock assessment, especially in the areas where the stock assessment has not been implemented. We therefore advocate that the intersessional work on ageing determination by the CCAMLR otolith network (CON) should be supported by the CCAMLR community as a systematic and supportive platform to conduct such work.