When I first delved into the world of harvest control rules and harvest strategies in 2011 during my time with WWF as their global tuna lead, I saw it as a critical opportunity to ensure sustainable fisheries. At the time, except for Southern Bluefin Tuna, none of the tuna RFMOs had established effective harvest strategies, despite the clear benefits they offered. It was a moment where the scientific community, NGOs, and some in the industry began to rally around this concept, recognizing that pre-agreed frameworks for managing fishing effort could mitigate the volatility and short-term pressures that often dominate RFMO negotiations.
A key challenge we encountered early on was the lack of understanding among stakeholders, particularly those outside the scientific realm. Harvest strategies were often perceived as a ‘black box’ solution—complex and intimidating. This is where capacity building became essential. Working on the Common Oceans Project, we hosted a series of workshops, using interactive tools to demystify harvest strategies and get participants actively involved in shaping their development. I remember one workshop vividly: participants were surprised to learn that there isn’t always a single “right” answer when mapping out a harvest strategy. Different components, such as reference points and harvest control rules, can be arranged in multiple ways, depending on the needs of specific fisheries. This flexibility is one of the greatest strengths of harvest strategies, allowing them to be tailored to the unique challenges each fishery faces.
While we’ve made significant progress—tuna RFMOs have adopted several harvest control rules in recent years—the true challenge lies ahead: effective implementation. In the Indian Ocean, for example, despite adopting harvest control rules for skipjack tuna, we’ve seen significant non-compliance with recommended catch limits. Moving forward, compliance isn’t just about enforcement. It’s about fostering goodwill, ensuring all stakeholders feel invested in the long-term goals of sustainable management, and developing fair allocation systems that work for everyone involved.
Monitoring and enforcement will also play a crucial role. The adoption of advanced technologies, like electronic monitoring systems and automated data analytics, will be essential to ensuring that harvest strategies work in practice. We’ve already seen fisheries adopt management procedures that integrate such tools, and it’s a model that will need to be expanded globally.
The journey of implementing harvest strategies over the past decade has been transformative. In 2014, I was thrilled to see mainstream media in the UK publish pieces on the need for harvest control rules and the European retailers demanding this—something unheard of when I began this work. Today, many of our GTA partners instantly understand the value of these strategies. This is a credit to all the capacity building that has happened. However, as we look ahead, ensuring robust compliance and continued capacity building will be critical to their long-term success.
At the Global Tuna Alliance (GTA), our global supply chain partners are deeply committed to pushing for progress in this area. Over the next five years, we will leverage our partnerships to advocate for the effective uptake and critical implementation of harvest strategies across all tuna RFMOs, ensuring that our tuna fisheries remain sustainable for future generations.
About the Author: With 20 years of experience in fisheries and marine conservation, Daniel Suddaby has a deep passion for the ocean, marine life, and sustainable fishing practices. He is an expert in tuna, advocacy, and sustainable market tools that drive change in fisheries and seafood supply chains. Prior to joining the GTA, Daniel founded and led the Tuna and Distant Water Fisheries Program at Ocean Outcomes, building effective relationships with longline tuna and supply chain companies to incentivize transformation through tools such as the Marine Stewardship Council (MSC) Fishery Improvement Projects. Previously, Daniel spent six years as the Deputy Leader of the World Wild Fund for Nature’s (WWF) global fisheries initiative, leading global engagement in tuna fisheries and advocacy in all Regional Fisheries Management Organisations (RFMOs), and providing strategic direction to WWF International on seafood engagement. He also has experience as a Senior Fisheries Certification Manager for the MSC.
The Inter-American Tropical Tuna Commission (IATTC) Annual Meeting concluded in Panama City last week, and several important decisions and developments will shape and advance fisheries management in the Eastern Pacific Ocean (EPO) in the coming years. Below are the key harvest strategy-related proposals discussed, their outcomes, and the work ahead for these critical fisheries.
Science-Management Dialogue (SMD) Working Group
The IATTC agreed to establish a formal Science-Management Dialogue (SMD) group to advance the management strategy evaluation (MSE) process in the EPO. First proposed by the IATTC Scientific Advisory Committee (SAC) in 2018, this group will provide a structured forum for guiding harvest strategies. Until now, the Commission has relied on informal MSE workshops, including the most recent one in December 2022, which, while useful for capacity building, lacked the authority to make formal recommendations. Thanks to Ecuador’s proposal, this group will be able to make formal recommendations to the Commission, streamlining progress toward effective and efficient management.
South Pacific Albacore (SPALB) Collaboration
Ecuador’s proposal for improved collaboration between the IATTC and WCPFC for the development of a SPALB harvest strategy was adopted. This collaboration is critical to ensuring effective Pacific-wide management of the stock. IATTC representatives joined the WCPFC’s SMD working group, ensuring that SPALB catches in the EPO are properly accounted for in WCPFC’s developing harvest strategy, which is scheduled for adoption this year.
Tropical Tunas (TT) and Bigeye Tuna (BET) Management
The tropical tunas measure dominated discussions at the meeting. This year’s yellowfin tuna assessment failed, leading to a prolonged debate over how long to extend the current measures. Delegates agreed to adopt a two-year rollover with triggers to review the measure if new information becomes available. While this measure was extended by two years, an MSE-tested harvest strategy is expected for bigeye next year. It is essential to maintain momentum toward this important milestone. IATTC has committed to scheduling at least two workshops/SMD meetings before the 2025 meeting to agree on management objectives and provide feedback on the preliminary MSE results.
Sharks: A New Path Forward
A proposal for improving shark management was adopted, which includes guidance on shark research. This adoption gives IATTC the mandate to work on developing a blue shark MSE, which would align with ongoing efforts at ICCAT and IOTC and improve management for this commercially and ecologically important species.
FAO and HarvestStrategies.org
Food and Agriculture Organization of the United Nations (FAO), in partnership with HarvestStrategies.org, hosted a well-attended side event at the IATTC meeting that highlighted the ongoing work to promote the adoption of harvest strategies for sustainable fisheries management. The event provided a platform to discuss the importance of implementing effective science-based management tools, with a particular focus on how harvest strategies can help safeguard vital fish stocks in the EPO and beyond.
Looking Ahead in 2025
IATTC made significant strides during its annual commission meeting, but much work remains. With several proposals adopted, including the formalization of the SMD working group and advancing cross-commission collaboration on SPALB, the groundwork is laid for continued progress. Harvest strategy priorities for 2025 include the adoption of harvest strategies for bigeye and Pacific bluefin tuna, the first SMD meeting, and the first climate change workshop, which is expected to highlight MSE and harvest strategies as tools to build climate-smart management systems.
Building on the momentum from this meeting, there is strong potential for member countries, scientists, managers, and stakeholders to collaborate effectively and ensure that modern, sustainable fisheries management in the EPO becomes a reality.
As we continue our deep dive into Management Strategy Evaluation (MSE) with Dr. Tom Carruthers, CEO of Blue Matter Science, this second and final part focuses on the advanced perspectives and future directions that shape the evolution of MSE in fisheries management. From the integration of Ecosystem-Based Fisheries Management (EBFM) principles to the impact of climate change and technological advancements, this discussion delves into how MSE can address the complex challenges facing our ocean. With his extensive experience, Tom shares invaluable insights on stakeholder engagement, international collaboration, and the need for modern innovation.
HS.org: How do you perceive the integration of EBFM principles within current MSE frameworks, and what strides must be taken to ensure a holistic approach to fisheries management that adequately protects marine biodiversity and supports the resilience of oceanic ecosystems and the sustainability of fisheries?
Tom: Ah, EBFM. Scarcely has there been a topic in fisheries of so much discussion and so little management action! A few years ago, I was asked to review the history of EBFM in fisheries. Despite many hundreds, maybe thousands of papers on the subject spanning more than 15 years, I could find evidence of only one fishery, Atlantic menhaden, where the principles of EBFM had shaped tactical management advice.
In my view, MSE is the only existing framework that can operationalize EBFM in the routine provision of tactical advice. This is because most ecosystem models are difficult to evaluate empirically. They often struggle to pass conventional standards of peer review for models used to inform management advice. MSE is expressly designed to navigate such hypotheses, potentially ending in an adopted harvest strategy robust to hypothetical scenarios for ecosystem dynamics.
HS. org: How do you involve stakeholders, including fishers and conservation interests, in the MSE process, and why is their involvement crucial?
Tom: A common reason for pursuing MSE is that the conventional stock assessment approach excludes the interests, experience, and values of the wider group of fishery participants. To many participants whose livelihoods are directly impacted by the results of stock assessments, the process can feel like a technologically complex exercise that removes all but a handful of nerdy scientists and reviewers (I am probably one of those!).
Stock assessment is like designing a car engine – it is necessarily complicated. MSE, on the other hand, is more about driving the car – the controls and the instrumentation. MSE asks stakeholders what they know and care about and how best to achieve those outcomes. All this should be presented in a package that is easy to drive, with the focus being on where we are going, not the complexities under the hood.
HS.org: How have recent technological advances and data analytics improved the MSE process?
Tom: We’ve come a long way from coding a bespoke MSE from scratch for every case study. Packages like FLR and OpenMSE standardize data inputs and harvest strategy configuration, allowing for greater focus on the more important issues, such as management objectives and the harvest strategies themselves.
My colleague, Dr. Adrian Hordyk, has been working hard on Slick, which is a package and online app that presents MSE results and diagnostics using graphics conceptualized by scientific communications experts. All together, this new technology has made MSE much more accessible and efficient.
HS. org: Where is there even more room for improvement?
Tom: MSE is still relatively new in the field of fisheries science and management. As a result, MSE processes tend to be rather ad-hoc and differ among fisheries management organizations and stocks. Much could be learned and synthesized from these various applications.
Having the tech to do MSE easily is one thing. What is needed now is an established framework, an MSE roadmap of sorts, that is integrated with stakeholders and the tech so that the process is standardized, efficient, and disciplined. As it happens, this is something we are currently working on; what are the odds?!
HS.org: How does MSE help adapt fisheries management to the impacts of climate change?
Tom: In a way, this is similar to the question about MSE and EBFM above.
Just about every fishery management organization I know of has an objective along the lines of ‘implement management considerate of changing climatic conditions.’ Despite a huge amount of scientific literature naming possible impacts, there are very few that make quantitative predictions that could be used to inform management advice. From my perspective, the forecasting of climate impacts on fish populations is necessarily hypothetical. I simply don’t think we can reasonably evaluate the credibility of an ‘end to end’ model that combines the predictions of climate, oceanographic, ecosystem, physiology, and fleet models to forecast impacts on a fishery. This is a problem for the conventional stock assessment approach that focuses on scientific veracity. This is less of a problem for MSE, which focuses on harvest strategy robustness, including robustness to highly uncertain future fishery scenarios. MSE might be the only framework we have available for establishing tactical advice for fisheries, providing us with harvest strategies that have demonstrated climate readiness.
HS.org: What roles do climate change and environmental variability play in shaping MSE approaches?
Tom: In general, these phenomena interact with the types of harvest strategies being tested. In an attempt to consider possible climate change or environmental conditions, MSEs often simulate changes in future stock productivity. Systematic productivity shifts tend to favor harvest strategies aiming to fish a consistent fraction of the stock over those that aim for a particular stock level. Variable stock productivity tends to favor harvest strategies that are responsive to recent data and allow for larger changes in management advice. Depending on resource conservation objectives, climate change, and other challenging environmental scenarios can be highly influential in harvest strategy selection if they provide an extreme stress test.
HS.org: What role does international collaboration play in developing and applying MSE, especially for transboundary fisheries?
Tom: Collaboration on both scientific and management aspects is absolutely essential. On the science side, an MSE for an international transboundary stock almost always requires the timely submission of standardized data from all fishing nations and a shared understanding of the important fishery uncertainties. Although these may already be a part of an existing stock assessment process, MSE tends to go further and allow for a wider range of data and hypotheses.
You could argue that the most important collaboration occurs at the management level, where I have less experience. Those managers must agree on aspects that may include the mundane, such as how often to update advice; the important, such as the principle management objectives; and the contentious, such as catch allocations. For transboundary stocks, international collaboration can be seen as an opportunity and a strength, but it is also a necessary precondition of MSE.
HS.org: In your opinion, which regional fisheries management organizations (RFMOs) are leading the way in adopting and refining MSE practices? What lessons can be learned from these pioneers that could be applied globally?
Tom: I think CCSBT does a remarkable job of including new genetic technology in their MSE frameworks, not just in defining fishery hypotheses but also in the harvest strategy itself. I think the lesson from CCSBT is to keep innovating and looking for new sources of scientific information.
Now, sadly, I am biased toward those processes I have had some direct involvement with:
The Canadian DFO is leading the way with data-poor and data-moderate MSE frameworks in B.C. DFO has established a framework for its groundfish fisheries that allows for the rapid adoption of simple empirical harvest strategies where a stock assessment is not feasible. The lesson from DFO is that MSE is not necessarily an exercise for data-rich stocks – the whole idea of establishing tactical advice in the face of uncertainty is very much a data-poor fishery problem.
HS.org: What do you see as the future directions for MSE in fisheries management over the next decade?
Tom: In the next decade, MSE should:
HS.org: What are the key research questions or areas that, if addressed, could significantly advance the field of MSE? Are there particular gaps in our current understanding or methodology that need to be filled?
Tom: For the most part, we still think of fishery management in terms of individual species and data streams for individual species. From the early work I have been doing, it is apparent that if we consider multiple stocks together, the data may have considerably more information about stock and exploitation levels. I think there must be more investigation into multi-species MSEs and harvest strategies. We could be ignoring a lot of information.
In most cases, MSE has been used to establish a harvest strategy that sets a catch limit. There needs to be a greater focus on the efficacy of mixed management options, such as a catch limit in combination with other regulations such as bag limits, effort limits, spatiotemporal closures, and size limits. Exploration of mixed management controls often reveals opportunities to obtain a superior trade-off in yield and resource conservation.
HS.org: What advice would you give fisheries managers and scientists who are new to MSE and looking to implement it in their region’s fisheries?
Tom:
Dr. Tom Carruthers’ insights highlight the critical role of innovation, collaboration, and a disciplined approach in advancing MSE to address the evolving challenges in modern fisheries management. By focusing on efficiency, stakeholder engagement, and adapting to environmental changes, MSE can provide robust and sustainable solutions for the future of our oceans. To learn more about MSE and Tom’s work, please visit www.bluematterscience.com.