Purse seine vessels account for about 66% of the world’s tuna catch. However, the number of purse seiners operating in the various oceans is not available from a single source. In this paper we estimate the number and fishing capacity of authorized tuna purse seiners based primarily on information available from the five tuna Regional Fishery Management Organizations (RFMOs).
After accounting for possible duplicate entries, we calculate that as of June 2025 there are at least 2,106 purse seiners fishing for tunas worldwide. This is surely an underestimate because many small-scale purse seiners or purse seiners operating in only one EEZ do not have to be listed on RFMO records of authorized fishing vessels, our primary source of data. Focusing on large-scale purse seiners (defined here as having 335 m3 fish hold volume or greater) that target tropical tunas (skipjack, yellowfin and bigeye), we calculate there are 675 such vessels with a combined fishing capacity of over 864,000 m3.
While the number of these vessels increased during the past year, aggregate fishing capacity increased by less than 1%. In terms of the proportion of these vessels flagged to developing or emerging economies relative to developed economies, we found that it has been increasing steadily since ISSF started producing these snapshot reports.
Of those 675 large scale purse seine vessels fishing for tropical tunas, 498 are registered on the ISSF Pro Active Vessel Register (PVR), which represent 74% in number and 83% in fish hold volume (FHV). About 12% of these 675 large-scale vessels are authorized to fish in more than one RFMO, which should be taken into account in any efforts to manage fishing capacity at a regional level.
A related infographic will be available.
Downloads: 2 | Views: 2
