Recent Indicative Trends in By-Catch of Sharks in the CAMLR Convention Area

Directed fishing on shark species in the Convention Area for purposes other than scientific research is prohibited under Conservation Measure 32-18. This CM further notes that any by-catch of sharks shall, as far as possible, be released alive. Recent trends in shark by-catch in the CAMLR Convention Area are examined here using information reported by vessels (C2) and scientific observers from 2017 to the start of 2023 fishing seasons. Both data sources show substantial gaps in reported shark by-catch, though they also suggests that shark by-catch has increased during this period. Contradictory trends are present between vessels and scientific observers in relation to shark by-catch in numbers, and those retained, discarded, and released. Specifically, observer data indicates a large number of retained shark by-catch, whereas vessel indicate near zero sharks retained. The discrepancy between these two data sources as to the fate of shark by-catch requires further examination. Mechanisms need to be explored to improve and strengthen data quality to better understand the trends and implications of shark by-catch in the Convention Area.