A review of conversion factors used in CCAMLR toothfish fisheries

The product to green-weight conversion factors used in the toothfish fishery are integral to the reporting of catches and reconciling those catches with data reported via the CDS. This paper reviews the data available on conversion factor in the C2 and Observer data as well as the factors that might influence those conversion factors. There was considerable inter-vessel variability as well as an apparent long-term trend in the most commonly reported conversion factors. This variability persisted even within the same processing code, suggesting that more details on the processing methods may be required to better understand the sources of this variability. The results suggest that a reconciliation between the reported catch for a vessel and the weight of product reported in a catch document submitted to the CDS should be based on a conversion of the ‘green weight’ for each haul in the C2 data to a product weight as this will be based on the most appropriate conversion factor available