Overview of Indian Ocean tropical tuna fisheries

Global catches of tropical tunas living in oceanic habitats, i.e., bigeye tuna (Thunnus obesus), skipjack tuna (Katsuwonus pelamis), and yellowfin tuna (Thunnus albacares), have steadily increased over the few last decades to exceed 5 million metric tons in 2019 (FAO 2021). The contribution of the Indian Ocean to the global catch of tropical tuna mainly increased from the early 1980s with the development of the large-scale purse seine fishery to reach a maximum of about 28%, while decreasing to about 21% in recent years, down to 1 million metric tons in 2019.

The overarching objective of this paper is to provide participants at the data preparatory meeting of the 24^th Session of the IOTC Working Party on Tropical Tunas (WPTT24(DP)) with a review of the status of the information available on Indian Ocean tropical tropical tunas. The document provides an overview of the data sets available in the IOTC Secretariat databases as of May 2022, the methods used for processing and assessing the reporting quality of the main data sets, and a description of the main trends and features of Indian Ocean tropical tuna fisheries over the last seven decades.