Updated ISSF Report Rates State of Tuna Stocks Worldwide
Of the total commercial tuna catch worldwide, 84% came from stocks at “healthy” levels of abundance, according to the March 2020 International Seafood Sustainability Foundation (ISSF) Status of the Stocks report. In addition, 15% of the total tuna catch was from overfished stocks, and 1% was from stocks at an intermediate level of abundance. The previous version of this report was released by ISSF in October 2019.In 2018, the catch of major commercial #tuna stocks was 5.1 million tonnes, more than half of which was #skipjack tuna. Click To Tweet
Several tuna stocks worldwide are considered overfished and/or subject to overfishing:
- The Atlantic Ocean bigeye, Eastern Pacific yellowfin, Indian Ocean yellowfin and Pacific bluefin tuna stocks are currently overfished and subject to overfishing.
- Overfishing is occurring as well on three other stocks: Eastern Pacific bigeye, Indian Ocean bigeye and Indian Ocean albacore.
- All skipjack and most albacore stocks are healthy.
Ratings for the following species have changed since last reported in October:
- The Spawning Biomass (SSB) ratio for Atlantic Ocean yellowfin has improved from yellow to green.
- The fishing mortality rate ratio for Indian Ocean bigeye has downgraded from green to orange.
- The fishing mortality ratio for Indian Ocean albacore has downgraded from green to orange.
ISSF publishes its signature Status of the Stocks report twice each year using the most current scientific data on 23 major commercial tuna stocks.
Key Statistics in the Report
- Abundance or “spawning biomass” levels: Globally, 65% of the 23 stocks are at healthy levels of abundance, 17.5% are overfished and 17.5% are at an intermediate level.
- Fishing mortality levels: 70% of the 23 stocks are experiencing a well-managed fishing mortality rate, and 30% are experiencing overfishing.
- Total catch: In 2018, the catch of major commercial tuna stocks was 5.1 million tonnes. 58% was skipjack tuna, followed by yellowfin (29%), bigeye (8%) and albacore (4%). Bluefin tunas accounted for 1% of the global catch.
- Largest tuna catches by stock: The five largest catches in tonnes, unchanged since the previous report, are Western Pacific Ocean skipjack, Western Pacific Ocean yellowfin, Indian Ocean skipjack, Indian Ocean yellowfin and Eastern Pacific Ocean skipjack.
- Tuna production by fishing gear: 66% of the catch is made by purse seining, followed by longline (10%), pole-and-line (8%), gillnets (4%) and miscellaneous gears (12%). These percentages changed minimally since the previous report.
About the Report
There are 23 stocks of major commercial tuna species worldwide — 6 albacore, 4 bigeye, 4 bluefin, 5 skipjack, and 4 yellowfin stocks. The Status of the Stocks summarizes the results of the most recent scientific assessments of these stocks, as well as the current management measures adopted by the RFMOs. Updated several times per year, Status of the Stocks assigns color ratings (green, yellow or orange) using a consistent methodology based on three factors: Abundance, Exploitation/Management (fishing mortality) and Environmental Impact (bycatch).
ISSF produces two reports annually that seek to provide clarity about where we stand — and how much more needs to be done — to ensure the long-term sustainability of tuna stocks: the Status of the Stocks provides a comprehensive analysis of tuna stocks by species, and the Evaluation of the Sustainability of Global Tuna Stocks Relative to Marine Stewardship Council (MSC) Criteria provides scores for the stocks and RFMOs based on MSC assessment criteria. The MSC-certified fisheries list (Appendix 2) in Status of the Stocks complements the Evaluation report. Together, these tools help to define the continuous improvement achieved, as well as the areas and issues that require more attention.
In addition, ISSF maintains a data-visualization tool based on its Status of the Stocks report. The “Interactive Stock Status Tool” is located on the ISSF website and accessible through the Status of the Stocks overview pageAbout the International Seafood Sustainability Foundation (ISSF)
The International Seafood Sustainability Foundation (ISSF) is a global coalition of scientists, the tuna industry and World Wildlife Fund (WWF) — the world’s leading conservation organization — promoting science-based initiatives for the long-term conservation and sustainable use of tuna stocks, reducing bycatch and promoting ecosystem health. Helping global tuna fisheries meet sustainability criteria to achieve the Marine Stewardship Council certification standard — without conditions — is ISSF's ultimate objective. In 2019, ISSF celebrated a “Decade of Discovery” as the organization completed its tenth year of scientific research, advocacy and industry engagement. To learn more, visit iss-foundation.org, and follow ISSF on Twitter, Facebook and Instagram.