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Author: Lynne Mandel

Longline fishing vessel

New Global Longline Fleet Analysis | Plus ISSF’s IATTC Priorities and the Latest Status of the Stocks

Featured News

ISSF Publishes First Global Analysis of Tuna Longline Fleets Across All Five Tuna RFMOs

New technical report provides the first harmonized global analysis of longline fleet composition, vessel characteristics, and fishing capacity

ISSF has published Characteristics of Longline Fleets Registered in Tuna Regional Fisheries Management Organizations as of June 2026, a new technical report by Dr. Josu Santiago. Drawing on vessel registry information from all five tuna RFMOs, the report provides the first harmonized global analysis of the authorized tuna longline fleet, including vessel characteristics, fishing capacity, flag State distribution, and vessels operating across multiple RFMO convention areas.

For more than a decade, ISSF has published annual snapshot reports tracking the global large-scale tropical tuna purse seine fleet. This new report extends that work to tuna longline fleets for the first time, providing complementary analyses of the composition and fishing capacity of the world’s principal tuna fishing fleets.

Read the Longline Fleet Report

 

Featured Position Statement

Priorities for Eastern Pacific Ocean Tuna Fisheries  

ISSF has published its position statement ahead of the 104th meeting of the Inter-American Tropical Tuna Commission (IATTC), which will take place August 31-September 4, 2026, in Lisbon, Portugal.

The statement outlines ISSF’s priorities for strengthening tuna fisheries management, including science-based conservation measures, harvest strategies, electronic monitoring and reporting, observer coverage, FAD management, bycatch mitigation, shark protections, transshipment regulation, labor and social issues, compliance, and fishing capacity.

Read the IATTC Position Statement

 

Did You Know?

97% of the global commercial tuna catch comes from stocks at healthy abundance levels, and nearly 100% comes from stocks not experiencing overfishing.

See the Status of the Stocks

 

Shark Awareness Day | Advancing Shark Conservation in Tuna Fisheries

July 14 marked Shark Awareness Day, an opportunity to recognize the important role sharks play in healthy ocean ecosystems and the collaborative efforts underway to reduce shark interactions in global tuna fisheries.

ISSF advances shark conservation through research, practical solutions to reduce shark bycatch and entanglement, guidance for fishers, and advocacy for stronger science-based fisheries management. This work helps address ecosystem impacts that are increasingly important to fisheries, seafood companies and broader sustainability initiatives while supporting continuous improvement across global tuna fisheries.

Featured Content

Q&A with Sonja Fordham

To mark Shark Awareness Day, ISSF spoke with Sonja Fordham, founder of Shark Advocates International and a member of ISSF’s Environmental Stakeholder Committee, about her perspective on the state of shark conservation.

In the Q&A, Sonja discusses why sharks are important to healthy ocean ecosystems, threats facing shark populations, encouraging advances in international fisheries management, promising innovations to reduce shark and ray bycatch, and the additional actions she believes tuna Regional Fisheries Management Organizations (RFMOs) should take to strengthen shark conservation.

Read the Q&A 

Featured Resource

Explore ISSF’s Shark Conservation Resources

ISSF’s shark conservation work spans research, practical tools, policy engagement and industry collaboration to help reduce shark bycatch, improve shark survival and advance science-based fisheries management.

Explore our shark conservation resources, including:

  • Shark bycatch mitigation research
  • Guidance for fishers on safe handling and release
  • Information on non-entangling fish aggregating devices (FADs)
  • Longline and purse seine skippers’ guidebooks
  • Shark conservation recommendations for tuna RFMOs

Whether you’re looking for the latest science, practical guidance or policy resources, ISSF’s shark resource hub brings together the tools and information that support continued progress in shark conservation across global tuna fisheries.

Explore Shark Conservation Resources 

ISSF in the News

Talking Tuna: “When science is followed, management works”
Marine Stewardship Council

ISSF HIGHLIGHTS HIGH COMPLIANCE WITH SCIENCE-BASED TUNA MEASURES
Fish Focus

Seafood Companies are Advancing Sustainable Tuna Fisheries Through Science, Transparency and Collaboration

Featured Content

Seafood Companies Collaborating Through ISSF to Advance Sustainable Tuna Fisheries

Collaboration across the seafood supply chain plays an important role in advancing sustainable tuna fisheries worldwide.

Today, 97% of the global commercial tuna catch comes from stocks at healthy abundance levels and nearly 100% of the catch comes from stocks not experiencing overfishing, according to ISSF’s Status of the Stocks report — reflecting decades of science-based fisheries management and coordinated action across governments, scientists, fishers, and seafood companies.

Through participation in the International Seafood Sustainability Association (ISSA), seafood companies work alongside scientists, environmental organizations, and other stakeholders to support science-based conservation measures, strengthen transparency, and advance responsible fishing practices. ISSA supports the work of ISSF, whose initiatives focus on improving tuna fisheries through research, innovation, and the implementation of science-based best practices.

Participation in ISSA provides tuna companies with opportunities to:

  • Support the development and implementation of science-based conservation measures
  • Demonstrate sustainability commitments through independent audits against ISSF conservation measures
  • Access transparency tools that support responsible sourcing, including the ISSF ProActive Vessel Register (PVR) and Vessels in Other Sustainability Initiatives (VOSI)
  • Collaborate with scientists, NGOs, and industry partners to advance improvements in global tuna fisheries

Retailer and buyer policies increasingly reference ISSF participation and the use of these transparency tools as part of their sustainability expectations.

Explore ISSF Participating Companies

 

Featured Resource

Why Seafood Companies Support ISSF

This downloadable resource highlights how participation in ISSF helps seafood companies advance sustainable tuna fisheries.

The guide outlines how participation helps companies:

  • Support science-based fisheries conservation
  • Demonstrate verified sustainability commitments
  • Access practical tools and resources developed by ISSF scientists and partners
  • Contribute to improvements in tuna fisheries management and fishing practices

Download the Guide

 

ICYMI

ISSF Annual Compliance Report Shows Continued High Conformance with Science-Based Conservation Measures for Sustainable Tuna Fisheries

ISSF published its latest ISSF Annual Conservation Measures & ProActive Vessel Register Compliance Report, providing independently audited results on implementation of ISSF Conservation Measures by participating companies and vessels listed on the ISSF ProActive Vessel Register (PVR).

For the 2025 audit period, the 24 ISSF participating companies achieved a 98.8% conformance rate across 32 ISSF measures. The report also summarizes aggregate compliance on the PVR for the vessel-related measures it tracks. Independent audits were conducted by MRAG Americas in accordance with established audit protocols.

“ISSF’s Conservation Measures are more than commitments on paper,” said Susan Jackson, ISSF President. “For the tenth consecutive year, participating companies achieved more than 90% conformance with ISSF Conservation Measures, reflecting a sustained commitment to implementing science-based best practices. Independent auditing and public reporting help demonstrate how those measures are being implemented by participating companies and PVR-listed vessels. Together, they provide an important level of accountability that supports ISSF’s science-based approach to tuna fisheries.”

Learn More

 

ISSF in the News

INFOFISH Announces Chair and Co-Chair for TUNA 2026

ISSF Annual Compliance Report Shows Continued High Conformance with Science-Based Conservation Measures for Sustainable Tuna Fisheries

Featured News

ISSF Annual Compliance Report Shows Continued High Conformance with Science-Based Conservation Measures for Sustainable Tuna Fisheries
Independent Audits Show Companies Achieved 98.8% Conformance While Aggregate PVR Vessel Compliance Reached 75.6%

ISSF has published its latest ISSF Annual Conservation Measures & ProActive Vessel Register Compliance Report, providing independently audited results on implementation of ISSF Conservation Measures by participating companies and vessels listed on the ISSF ProActive Vessel Register (PVR).

For the 2025 audit period, the 24 ISSF participating companies achieved a 98.8% conformance rate across 32 ISSF conservation measures. The report also summarizes aggregate compliance on the ISSF ProActive Vessel Register (PVR) for the vessel-related measures it tracks. Independent audits were conducted by MRAG Americas in accordance with established ISSF audit protocols, providing stakeholders with transparent, independently verified information on implementation of ISSF Conservation Measures by participating companies and PVR vessels.

“ISSF’s Conservation Measures are more than commitments on paper,” said Susan Jackson, ISSF President. “For the tenth consecutive year, participating companies achieved more than 90% conformance with ISSF Conservation Measures, reflecting a sustained commitment to implementing science-based best practices. Independent auditing and public reporting help demonstrate how those measures are being implemented by participating companies and PVR-listed vessels. Together, they provide an important level of accountability that supports ISSF’s science-based approach to tuna fisheries.”

Read More

 

Featured Infographic

Our “Change Over Time” line graph tracks changes since 2015 in the conformance percentages of ISSF participating companies in aggregate with ISSF conservation measures. It also shows changes in the number of companies and measures from year to year.

This graphic tracks compliance based on data published in the ISSF Annual Conservation Measures & ProActive Vessel Register Compliance Report.

View

 

Featured Video

Building on Our Successes — Transparent Accountability

At the launch of ISSF’s 2023-2027 Strategic Plan for sustainable fisheries, ISSF President Susan Jackson reflects in this video on the organization’s compliance process for participating seafood companies and tuna vessels.

Watch

 

ICYMI

Reflecting on a Decade of Measurable Progress in Global Tuna Fisheries

“World Tuna Day, observed annually on May 2, offers an opportunity to reflect on the state of one of the world’s most important seafood resources. This year also marks a milestone: 10 years since the United Nations formally established World Tuna Day, and more than a decade of sustained, measurable progress in global tuna fisheries.”

Read more from Susan Jackson

 

 

Science Driving Progress in Global Tuna Fisheries | FAO Recognition Headlines This Issue

Featured News

FAO Features ISSF Contributions in Flagship Global Fisheries Report
Report Recognizes ISSF Skippers’ Training Program and Biodegradable FAD Innovation

The Food and Agriculture Organization of the United Nations (FAO) has featured ISSF in its newly released State of World Fisheries and Aquaculture 2026 report, one of the world’s most widely referenced assessments of global fisheries and aquaculture.

Across several chapters, the report recognizes ISSF’s contributions through the collaborative Common Oceans Tuna project. Among the examples featured are ISSF’s long-running Skippers’ Workshop program, efforts to advance bycatch mitigation and the transition to non-entangling and biodegradable fish aggregating devices (FADs), and collaborative research that led to the development of the innovative jelly-FAD.

The publication also recognizes ISSF scientific expertise through the contribution of ISSF scientist Dr. Hilario Murua, who served as a co-author of the chapter assessing the status of the world’s marine fishery resources.

Published every two years, FAO’s State of World Fisheries and Aquaculture report provides governments, fisheries managers, industry, researchers, and other stakeholders with an authoritative overview of the status and future direction of global fisheries and aquaculture.

Read the FAO Report

 

Featured Content

ISSF Report Reviews Environmental Impacts and Mitigation Efforts in Tuna Fisheries
Updated Review Examines Ecosystem Impacts, RFMO Measures, and Mitigation Practices

An ISSF technical report reviews how different tuna fishing methods interact with non-target species and marine ecosystems, along with measures being implemented to reduce those impacts. It also summarizes MSC-certified tuna fishery performance, tuna RFMO conservation measures adopted through 2025, and ISSF conservation measures that support continual improvement across global tuna fisheries.

Among the report’s findings:

  • Purse seine fisheries account for 66% of the global commercial tuna catch, making continued mitigation efforts particularly important.
  • Research cited in the report estimates non-tuna catch in purse seine fisheries at approximately 1.4% of target tuna catch—or 0.92% when minor tunas and bonitos are excluded.
  • Observer data reviewed in the report found sharks and rays combined represented less than 0.5% of total catch in purse seine FAD sets.
  • All tropical tuna RFMOs now prohibit netting material in drifting FADs, while tuna fisheries continue expanding the use of non-entangling and biodegradable FAD designs to reduce entanglement risks for sharks and sea turtles.

The report is part of ISSF’s ongoing work to compile and assess science-based information related to tuna fisheries, ecosystem impacts, and mitigation measures worldwide.

Read the Report

 

Featured Video

Featured in this month’s State of World Fisheries and Aquaculture report, ISSF’s non-entangling and biodegradable FAD work includes hands-on workshops with purse-seine fishers in Ghana, where participants learned to build fish aggregating devices (FADs) using natural, locally available, and biodegradable materials to help reduce plastic pollution in the ocean. Working with fisheries scientists, they constructed three bio-FAD designs from start to finish.

Watch

 

Featured Resource

MSC-Certified Tuna Fisheries

A table shows tuna fisheries worldwide that either have been certified by the Marine Stewardship Council (MSC) or are currently undergoing a full assessment to become certified. Helping tuna fisheries to meet and maintain sustainability criteria to achieve the MSC certification standard is ISSF’s ultimate objective. More than half of the world’s annual tuna catch — or about 3.1 million tonnes — comes from MSC-certified fisheries.

Tuna fishery names are linked to their pages on the MSC Track a Fishery site, where users can access additional information. The table can be sorted and filtered by column and is updated quarterly. It was last updated in June 2026.

Explore the Table

 

Advancing Monitoring in Tuna Fisheries | PLUS: Setting the Record Straight on IUU Fishing

Featured News

Scaling Electronic Monitoring in Tuna Fisheries

As discussions at the Our Ocean Conference highlight the role of technology in sustainable fisheries, electronic monitoring continues to gain momentum across tuna fisheries. Once limited to pilot projects, EM is increasingly being incorporated into fisheries monitoring programs, supported by regional standards, technological advances, and growing operational experience.

As implementation expands, attention is increasingly focused on how electronic monitoring can support fisheries data collection, compliance, and transparency across tuna fisheries.

Learn More About Electronic Monitoring

 

Featured Content

IUU Fishing, Facts, and Fisheries Management
Setting the Record Straight on IUU Fishing in the Western and Central Pacific

Illegal, unreported, and unregulated (IUU) fishing remains a significant concern in global fisheries, including in the Western and Central Pacific Ocean. In a guest blog for ISSF, Dr. John Hampton examines available data and fisheries management information to provide context on IUU fishing estimates and their interpretation. The blog explores how IUU fishing is assessed, the role of regional management measures, and why accurate use of fisheries data is important to informed discussions about tuna sustainability.

Read the Blog

 

Featured Resource

Transparency Tools for Tuna Fisheries
Accessible Information on Vessel Practices and Sustainability Initiatives

ISSF’s ProActive Vessel Register (PVR) and Vessels in Other Sustainability Initiatives (VOSI) help support transparency across global tuna fisheries by providing public access to independently audited vessel-level sustainability information.

At the end of 2025, the PVR listed an all-time-high 1,839 vessels — representing approximately 83% of large-scale tropical tuna purse-seine fishing vessel hold capacity globally. VOSI also surpassed 1,200 vessel registrations, expanding visibility into vessel best practices across fleets. The PVR includes vessels audited on their compliance with select sustainability measures directly linked to ISSF conservation measures. VOSI complements the PVR by providing visibility into additional vessel practices and sustainability initiatives beyond compliance requirements reflected on the PVR.

Together, these tools help provide stakeholders with verified, accessible information on vessel-level sustainability practices across global tuna fisheries.

Explore PVR and VOSI

 

ISSF in the News

Market Commitment Evaluation Framework ensuring consistency in sustainability data collection, reporting
Seafood Source

Recognizing World Sea Turtle Day | Reducing Risks to Sea Turtles

June 16 marks World Sea Turtle Day, an opportunity to highlight practical improvements to protect sea turtles in and around tuna fisheries.

Across tuna regions, fishers, scientists, seafood companies, conservation organizations, and fisheries managers continue implementing solutions that support sea turtle conservation. From improved non-entangling fishing gear designs and safer handling practices to nesting conservation projects and evolving fisheries management measures, a range of efforts are contributing to continuous improvement.

 

Featured Content

Nesting Site Protection: Local Projects, Global Impact

Safeguarding nesting sites is critical to sea turtle conservation. Threats such as coastal development, predation, and human disturbance can significantly affect hatchling survival.

Through an annual fund exceeding $100,000, ISSF supports on-the-ground nesting and community outreach projects in countries such as Brazil, Tanzania, Peru, and Oman. These projects—made possible by ISSF Participating Companies including Bumble Bee, Thai Union, Tri Marine, and StarKist—help protect nesting beaches, engage local communities, and support sea turtle conservation efforts around the world.

View Sea Turtle Conservation Projects

 

Advancing FAD Best Practices

Fish aggregating devices (FADs) are an important fishing tool in many tuna fisheries. Over time, ISSF Conservation Measures and RFMO requirements have supported improvements in FAD designs to reduce entanglement risks for sea turtles and other marine species.

Today, non-entangling FAD designs are increasingly used throughout tuna fisheries, while researchers continue to innovate biodegradable materials and other approaches to further reduce ecosystem impacts.

Download the Jelly-FAD Construction Guide 

 

Bycatch Mitigation: Tools, Training & Best Practices

Reducing risks to sea turtles also depends on what happens when interactions with vessels occur.

ISSF supports practical approaches that help fishers safely handle and release incidentally captured turtles, including:

  • Longline skipper workshops focused on safe handling and release techniques
  • Guides, posters, and infographics that promote onboard best practices
  • Specialized tools such as de-hookers, line cutters, and nets
  • Fishing practices designed to help reduce sea turtle interactions

Explore Our Skippers Guidebook

 

Featured Resource

“Saving Sea Turtles” Infographic

This visual guide helps fishers identify safe handling techniques to maximize survival after incidental capture.

Download the Infographic

 

 

 

 

 

Transparency in Focus | Ahead of World Anti-IUU Fishing Day, ISSF content examines IUU fishing, transshipment oversight, and vessel transparency tools

Featured News

IUU Fishing, Facts, and Fisheries Management
Setting the Record Straight on IUU Fishing in the Western and Central Pacific

Illegal, unreported, and unregulated (IUU) fishing remains a significant concern in global fisheries, including in the Western and Central Pacific Ocean. In a new blog, Dr. John Hampton examines available data and fisheries management information to provide context on IUU fishing estimates and their interpretation. The blog explores how IUU fishing is assessed, the role of regional management measures, and why accurate use of fisheries data is important to informed discussions about tuna sustainability.

Read the Blog

 

Featured Content

Three Oceans, Five Systems, One Shared Challenge: Strengthening Tuna At-Sea Transshipment Governance
Comparing Transshipment Rules Across Tuna RFMOs

At-sea transshipment remains an important operational practice in many tuna fisheries, but oversight requirements differ across oceans and regional fisheries management organizations. This blog reviews how the five tuna RFMOs regulate at-sea transshipment and highlights recent progress toward stronger monitoring, reporting, and transparency measures. It also identifies opportunities to improve consistency and strengthen governance across tuna fisheries worldwide.

Read the Blog

 

Featured Resource

Transparency Tools for Tuna Fisheries
Accessible Information on Vessel Practices and Sustainability Initiatives

ISSF’s ProActive Vessel Register (PVR) and Vessels in Other Sustainability Initiatives (VOSI) help support transparency across global tuna fisheries by providing public access to independently audited vessel-level sustainability information.

At the end of 2025, the PVR listed an all-time-high 1,839 vessels — representing approximately 83% of large-scale tropical tuna purse-seine fishing vessel hold capacity globally. VOSI also reached more than 1,200 vessel registrations, reflecting expanded tracking of vessel best practices across fleets. The PVR includes vessels audited on their compliance with select sustainability measures directly linked to ISSF conservation measures. VOSI complements the PVR by providing visibility into additional vessel practices and sustainability initiatives beyond compliance requirements reflected on the PVR.

Together, these tools help provide stakeholders with verified, accessible information on vessel-level sustainability practices across global tuna fisheries.

Explore PVR and VOSI

 

ISSF in the News


ISSF’s PVR and VOSI programs turning data into value for tuna supply chains
Seafood Source

IOTC commits to reducing yellowfin tuna catch over time, advances monitoring measures
Seafood Source

ISSF Welcomes Progress But Highlights Gaps After IOTC Meeting
The Fishing Daily

Nina Rosen Joins ISSF Environmental Stakeholder Committee
Fish Focus

 

Updated Report Reviews Environmental Impacts in Tuna Fisheries | Report Examines Fishing methods, RFMO Measures, & Mitigation Efforts

Featured News

Updated ISSF Report Reviews Environmental Impacts and Mitigation Efforts in Tuna Fisheries
Report Examines Fishing Methods, RFMO Measures, and Evolving Best Practices

ISSF’s latest technical report provides an updated review of how different tuna fishing methods interact with non-tuna species and marine ecosystems, along with the measures being implemented to help reduce those impacts. The report also reviews scores from MSC-certified tuna fisheries alongside tuna RFMO conservation measures adopted through 2025 and ISSF conservation measures aimed at supporting continual improvement across global tuna fisheries.

Among the report’s findings:

  • Purse seine fisheries account for 66% of the global commercial tuna catch, underscoring the importance of large-scale mitigation efforts across global tuna fisheries.
  • The report cites research estimating the global non-tuna catch rate in purse seine fisheries at approximately 1.4% relative to target tuna catch — or 0.92% when minor tunas and bonitos are excluded.
  • Observer data reviewed in the report found sharks and rays combined represented less than 0.5% of total catch in purse seine FAD sets.
  • All tropical tuna RFMOs now prohibit netting material in drifting FADs, while tuna fisheries continue expanding the use of non-entangling and biodegradable FAD designs to help reduce entanglement risks for sharks and sea turtles.

The report is part of ISSF’s ongoing work to compile and assess science-based information related to tuna fisheries, ecosystem impacts, and mitigation measures worldwide.

Read the Report

 

Featured Content

Updated Skippers’ Guidebook Supports Sustainable Purse-Seine Fishing Practices
4th Edition Incorporates New Mitigation Tools, FAD Guidance, and Practical At-Sea Resources

ISSF recently released the fourth edition of its Skippers’ Guidebook to Sustainable Purse Seine Fishing Practices, an updated resource designed to help tuna fishers apply science-based best practices at sea. Available in multiple languages, the guidebook provides practical guidance on reducing impacts on non-target species and marine ecosystems while supporting continual improvement across tuna fisheries.

New updates include:

  • Expanded guidance on non-entangling and biodegradable FAD designs
  • Updated bycatch mitigation techniques and safe-release practices for sharks and rays
  • New visuals and tools to support species identification and handling
  • Additional information on FAD monitoring, data collection, and ecosystem impacts
  • Streamlined overviews of the five tuna RFMOs and updated ISSF Conservation Measures

The guidebook draws on at-sea trials, fisher feedback, scientific research, and collaborative testing of mitigation tools — including shark release ramps and manta ray sorting grids developed with tuna fishers and ISSF scientists.

As part of ISSF’s global fisher-outreach program, the guidebook also supports requirements tied to ISSF conservation measures and the ProActive Vessel Register (PVR).

Explore the Guidebooks

 

ICYMI

IOTC Advances Several Monitoring and Bycatch Priorities While Tuna Conservation Challenges Remain

As the Indian Ocean Tuna Commission (IOTC) annual meeting concludes, ISSF welcomes several constructive outcomes for Indian Ocean tuna fisheries, particularly on bycatch mitigation, transshipment oversight, and continued investment in science-based management procedures. However, ISSF remains concerned that the adopted yellowfin tuna measure does not fully align with IOTC Scientific Committee advice.

Continue Reading

 

ISSF in the News

Nina Rosen Joins ISSF Environmental Stakeholder Committee
Fish Focus

 

IOTC Advances Several Monitoring and Bycatch Priorities While Tuna Conservation Challenges Remain

Featured News

IOTC Advances Several Monitoring and Bycatch Priorities While Tuna Conservation Challenges Remain

As the Indian Ocean Tuna Commission (IOTC) annual meeting concludes, the International Seafood Sustainability Foundation (ISSF) welcomes several constructive outcomes for Indian Ocean tuna fisheries, particularly on bycatch mitigation, transshipment oversight, and continued investment in science-based management procedures. However, ISSF remains concerned that the adopted yellowfin tuna measure does not fully align with IOTC Scientific Committee advice.

Ahead of this year’s annual meeting, ISSF urged the Commission to build on recent progress in Indian Ocean tuna fisheries management by focusing on strengthening science-based tuna conservation measures and improving monitoring systems and bycatch mitigation measures.

The final meeting outcomes reflect progress in several of these areas, particularly for mobulid ray conservation, transshipment oversight, and continued investment in management procedures. Yet important gaps remain on tuna conservation measures, particularly yellowfin catch limits, and monitoring systems.

Continue Reading