Evaluating length-frequency data and length-based performance indicators in new and exploratory fisheries

Length-frequency data are routinely collected in CCAMLR’s fisheries and used as inputs to stock assessments. In CCAMLR’s new and exploratory fisheries, stock assessment techniques are still in development and robust conclusions on stock status based on length-frequency data alone have been difficult. In this paper, we show that length-frequency data on their own have little inherent conclusive information about stock status. While length-frequency data can be useful in assessments when integrated with other more informative estimators for stock abundance and productivity, interpretation of trends in length-frequency data can be misleading and should be avoided.