The latest report from the International Seafood Sustainability Foundation (ISSF), released in March 2025, highlights significant strides in the sustainability of global tuna stocks. This update is crucial for understanding the health of tuna fisheries, which are vital for food security and economic stability worldwide. Below, we explore the key findings, potential reasons for improvement, and what this means for the industry and conservation efforts.
Key Findings
The ISSF’s March 2025 report, titled “Status of the World Fisheries for Tuna,” reveals:
- Overfished stocks now account for just 2% of the global catch, a notable decrease from 10% in the previous report, indicating recovery in previously depleted stocks.
- Stocks at an intermediate level of abundance have risen to 10%, up from 2%, suggesting more stocks are moving toward healthier levels.
- Healthy stocks remain stable at 88% of the global catch, ensuring a robust supply for the industry.
This shift is unexpected, as it shows a rapid improvement in stock health, particularly with overfished stocks dropping so significantly, which could influence future fishing policies and consumer choices.
Implications
The improved sustainability likely benefits the tuna industry by ensuring a stable supply, supporting economic growth in tuna-dependent regions, and enhancing food security, given tuna’s role as a key protein source. For conservation, it suggests that current efforts are effective, potentially reducing the risk to marine biodiversity. Consumers may see increased trust in sustainably sourced tuna, possibly leading to higher demand for certified products.
Survey Note: Detailed Analysis of Global Tuna Stock Sustainability Progress
Introduction and Context
The International Seafood Sustainability Foundation (ISSF), a global partnership among the tuna industry, scientists, and environmental organizations, released its March 2025 “Status of the World Fisheries for Tuna” report, also known as the “Status of the Stocks” report. This biannual publication, reviewed by ISSF’s Scientific Advisory Committee, provides a comprehensive analysis of 23 major commercial tuna stocks, focusing on abundance, exploitation/management, and environmental impact (bycatch). The report, published on March 10, 2025, and covered by Undercurrent News on March 17, 2025, highlights significant progress in tuna stock sustainability, with overfished stocks now accounting for just 2% of the global catch, down from 10%, and intermediate stocks at 10%, up from 2% compared to the November 2024 findings.
Key Findings and Statistical Breakdown
The report’s key statistics, based on the proportion of the global catch, are as follows:
| Stock Status | March 2025 (%) | November 2024 (%) | Change |
|---|---|---|---|
| Healthy Abundance Levels | 88 | 88 | No change |
| Intermediate Abundance | 10 | 2 | +8 percentage points |
| Overfished | 2 | 10 | -8 percentage points |
Additionally, the report notes that 91% of tuna stocks are not experiencing overfishing, a four-percentage-point improvement since November 2024, indicating reduced fishing pressure on vulnerable stocks. The 2023 catch of major commercial tuna stocks totaled about 5.2 million tons, providing context for the scale of these proportions.
This breakdown is distinct from the percentage of stocks by number, where the March 2025 report indicates 65% at healthy levels, 26% at intermediate, and 9% overfished, highlighting the difference between stock counts and catch proportions.
Factors Contributing to Improvement
Several factors likely contributed to this progress, inferred from ISSF’s broader activities and historical reports:
- Enhanced RFMO Management: Regional Fishery Management Organizations (RFMOs) have implemented stricter regulations, such as total allowable catch (TAC) recommendations for stocks like Indian Ocean bigeye and Southern bluefin, as seen in previous reports. For instance, the Indian Ocean Tuna Commission (IOTC) adopted new measures for skipjack tuna management, potentially aiding recovery.
- Sustainable Fishing Practices: The industry has increasingly adopted practices like non-entangling and biodegradable fish-aggregating devices (FADs), with IATTC setting deadlines for their use by 2025 and 2029, respectively, reducing bycatch and ecosystem impact.
- Stock Recovery Programs: Targeted efforts, such as reduced fishing quotas and protected areas, have likely helped stocks like Eastern Pacific Ocean bigeye and Pacific Ocean bluefin, which showed improvements in sustainability ratings in recent updates.
- Scientific Research and Monitoring: ISSF’s emphasis on scientific assessments, including acoustic discrimination technology and electronic monitoring systems, has provided data for informed decision-making, as evidenced by their interactive data-visualization tools for stock status.
These efforts align with ISSF’s mission to undertake science-based initiatives for long-term conservation, reducing bycatch, and promoting ecosystem health, as outlined on their website.
Implications for Industry and Conservation
The improved sustainability has multifaceted implications:
- Economic Stability: With 88% of the catch from healthy stocks, the tuna industry, a multi-billion-dollar sector, can expect stable supply chains, supporting livelihoods in regions like the Western and Central Pacific, which account for 52% of global tuna production. This stability is crucial for companies like Frinsa, a top tuna buyer and ISSF member since 2010, as noted in their participation details.
- Food Security: Tuna, a vital protein source for millions, ensures nutritional security, particularly in developing countries. The reduction in overfished stocks to 2% mitigates risks of supply shortages, supporting global food systems.
- Biodiversity Conservation: Healthy tuna populations contribute to marine ecosystem balance, reducing pressure on non-tuna species and habitats, as studied in ISSF’s research on tuna fishing impacts.
- Consumer Confidence: The shift to more sustainable stocks may increase demand for Marine Stewardship Council (MSC)-certified tuna, enhancing consumer trust. ISSF’s evaluation using MSC criteria for 23 stocks, available at this link, supports this trend.
Comparative Analysis with Previous Reports
Historically, the proportion of catch from overfished stocks has varied. In March 2022, it was 9.2%, and in March 2023, 11%, as per ISSF reports. The current 2% is a significant improvement, possibly due to recent RFMO measures and industry compliance, as seen in ISSF’s compliance reports. The increase in intermediate stocks from 2% to 10% suggests a transitional phase for some stocks, potentially moving toward healthy levels, as evidenced by improvements in stocks like Atlantic Ocean/Mediterranean albacore in November 2024 reports.
Challenges and Future Outlook
Despite progress, challenges remain, such as high uncertainty in monitoring some stocks (e.g., Mediterranean albacore) and ongoing overfishing in specific regions like the Indian Ocean. ISSF’s advocacy for electronic monitoring standards, adopted by the Indian Ocean Tuna Commission, aims to address these gaps, as detailed in their blog. Continued collaboration among stakeholders is essential to maintain this trajectory, with ISSF’s interactive tools, like the stock status visualization at this page, aiding transparency and decision-making.
Conclusion
The March 2025 ISSF report underscores a promising trend in global tuna stock sustainability, with overfished stocks at a record low of 2% and intermediate stocks rising to 10%. This progress, likely driven by enhanced management, sustainable practices, and scientific monitoring, bodes well for the tuna industry, conservation, and consumers. However, vigilance is required to ensure these gains are sustained, with the full report available for download at ISSF’s website for further details.