The latest snapshot of the world’s large-scale tuna purse seine fleet by the International Seafood Sustainability Foundation (ISSF) indicates that fishing capacity has seen a 3% increase, while the number of such vessels has marginally declined.
The ISSF analysis shows roughly 650 vessels defined as large-scale purse-seine (LSPS) vessels are fishing for tropical tuna species, a slight decrease of 0.3% from last year, with a combined capacity of 863,000 cubic metres, a 3% increase from last year.
Purse seiners catch approximately 66% of the 5.2 million tonnes of tuna caught annually worldwide. ISSF analyses and aggregates information from the five tuna regional fisheries management organizations (RFMOs) and other sources to create its annual report focusing on LSPS vessels targeting skipjack, yellowfin and bigeye tunas.
According to ISSF, the number of LSPS vessels (those with a fish hold volume of over 335 cubic metres) fluctuates due to several factors, such as new vessels being constructed or vessels no longer active due to being sunk or scrapped. In addition, the report aims to estimate active capacity, omitting vessels not listed on the RFMO Authorized Vessel Records when the “snapshot” was taken.
This year’s report shows that 20 LSPS vessels built after 2012 – including seven built in 2023 and one in 2024 – were added to the tropical tuna RFMO authorized vessel lists since the prior Snapshot released in June 2023. Around half of these newly constructed vessels are flagged to Indonesia and have an FHV close to the 335 cubic metre threshold.
The number of LSPS vessels slightly decreased to 650 vessels compared to the 652 reported last year. These return a 863,000 cubic metres of combined capacity – up from the 841,000 cubic metres reported a year ago.
Notably, most LSPS vessels (504) are registered on the ISSF ProActive Vessel Register (PVR), and PVR-registered LSPS vessels represent 78% of the total number and 84% of FHV. The independently audited PVR is one of four ISSF public vessel lists that foster transparency in tuna fisheries. Fishing vessels can be registered on the PVR to show how they follow best practices supporting sustainable tuna fisheries.
The “snapshot” report summarizes all changes that have taken place annually since 2012 and shares additional findings. Among these are the observation that the total number of all purse seine vessels worldwide increased from 1837 in 2023’s report to 1939 today. Around 12% of large-scale vessels are authorised to fish in more than one RFMO, which has to be taken into account in any efforts to manage fishing capacity at a regional level. Of the the tuna RFMOs, the Western and Central Pacific Fisheries Commission still has the highest LSPS registrations with 305.
ISSF states that the quality of data in RFMO records has improved in recent years, but substantial gaps remain.
‘Tuna RFMO members exercise greater quality control of the vessel data they submit to the tRFMOs for the vessel records and tRFMOs adopt vessel registry requirements that include quality control mechanisms,’ its report recommends.
