British Indian Ocean Territory Biodiversity Action Plan: Yellowfin Tuna

Historical fisheries records from British Indian Ocean Territory (BIOT) show that yellowfin tuna were ubiquitous across the territory. The highest catch rates of yellowfin by the historical longline fishery – which targeted large, mature individuals – occurred between September and December, possibly indicating an influx of individuals into BIOT during these months. However, there was significant inter annual variation in catches, possibly linked to climatic variation. Furthermore, purse seine fishers, which generally caught smaller yellowfin, only targeted BIOT during November and December, again, possibly indicating a greater number of yellowfin present in BIOT during this period.