Assessment of South African round herring : Initial results

Round herring (Etrumeus whiteheadi), also referred to as Redeye, has been landed by the South African purse seine fishery for small pelagic fish since 1958, and, since the mid‐1970s, has been the species with the third highest landed tonnage after sardine and anchovy. A quantitative stock assessment of round herring was attempted in 2010, but the model did not provide an adequate fit to the data (de Moor and Butterworth 2010a,b). This document provides initial results from a new stock assessment of the South African round herring resource. The round herring fishery has been managed with an annual Precautionary Upper Catch Limit (PUCL) of 100 000t for many years (e.g. DEA 1990, Coetzee and Butterworth 2012, see Figure 1), decreasing to 60 000t in 2022 following an estimate of November 2021 survey abundance below 750 000t (DFFE 2022). It is hoped that an acceptable assessment will provide the Department of Forestry, Fisheries and the Environment (DFFE) with sound advice regarding the historical exploitation levels and current status of this resource. Such an assessment could then also be used as an Operating Model to simulation test Candidate Management Procedures for this fishery. Some questions remain (listed under Further Work) before the assessment can be finalised and further robustness to key model assumptions and/or parameters tested.