A Groundbreaking Moment in Marine Science: The Largest Ocean Predation Event Ever Recorded
In one of the most significant findings in marine biology, a team of oceanographers from MIT and Norway observed an extraordinary predation event—a natural phenomenon unlike anything previously recorded. The event involved millions of capelin, a small fish crucial to Arctic ecosystems, forming a vast shoal (a large number of fish swimming together) spanning over 10 kilometres. In response, a massive shoal of Atlantic cod gathered and attacked the capelin shoal, consuming more than 10 million capelin fish in a matter of hours.
This observation was made possible through the use of advanced sonic imaging technology called Ocean Acoustic Waveguide Remote Sensing (OAWRS). This technology enabled the researchers to track fish movements and distinguish between species by detecting unique resonances from their swim bladders—tiny air-filled sacs that resonate with specific frequencies for each fish type. Capelin resonate at high frequencies like a piano's high notes, while cod sound more like a large bell.
By capturing this data, the team saw how capelin, typically scattered individuals, grouped together in response to the presence of cod, forming a “defensive shoal.” The cod, in turn, responded as a cohesive force, creating what one researcher described as an intense “battle for survival.”
Interested in hearing more and learning from industry experts?
Join us at Oceanology International and expand your Blue Tech and Ocean knowledge through strategic conferences.
March 10-12, 2026 | ExCeL London
Industry Insights: What This Event Means for Marine Science and Conservation
1. Enhanced Understanding of Ecosystem Dynamics
Observing predator-prey interactions on this scale provides a wealth of information on how such relationships can shift ecosystem balances rapidly. Understanding these dynamics at large scales helps researchers assess the resilience of fish populations. Events like these can drastically impact local ecosystems but are typically manageable within robust populations. However, with increased climate pressures, changes in marine hotspots, or declines in species diversity, such predation events could have severe ripple effects. This insight is essential for marine biologists and conservationists who work to maintain balanced, healthy marine ecosystems.
2. The Role of Advanced Acoustic Technology in Marine Research
This study showcases how innovative technology can revolutionise ocean observation. OAWRS allowed scientists to “see” into a marine event without disrupting it, providing clear data on fish behaviour in response to predator presence. This technology also has broader applications, enabling researchers to detect fish populations over large areas and to better monitor shifts in fish behaviours due to environmental changes. For industries involved in sustainable fishing and marine conservation, tools like OAWRS open new doors for monitoring fish stocks and ensuring responsible resource management.
3. Potential Implications for Sustainable Fishing Practices
Capelin are a foundational food source for various predators, including cod, seals, and seabirds, which makes them integral to the Arctic food web. Observing how a single, massive predation event can consume such a significant portion of a capelin shoal has important implications for sustainable fishing practices. Overfishing of capelin or other keystone species could lead to food shortages for other marine life, potentially causing collapses within these ecosystems. By identifying how different species interact and the scale at which these interactions occur, fisheries can better manage quotas and ensure species populations remain balanced.
4. Climate Change and the Future of Ocean Hotspots
As the global climate changes, the stability of marine ecosystems faces growing threats. Temperature shifts, ocean acidification, and habitat loss are impacting marine species’ survival and behaviours. This study’s insights into how capelin and cod interact within specific ecological hotspots shed light on the importance of these areas for sustaining fish populations. If the ocean’s temperature rises or habitats are further fragmented, hotspots may shrink or disappear, which could lead to increased pressures on marine species. This data is invaluable for policy-making, guiding protections for critical areas that harbour diverse marine life and are especially vulnerable to climate change impacts.
Explore the latest technologies shaping the future of Ocean Exploration, Sustainability and the Blue Economy
March 10-12, 2026 | ExCeL London
Be updated with Oceanology International and follow us on social media
Looking for something else?
For further information, please contact:
Mike Enser, Marketing Manager
Oceanology International
Tel: +44 (0)20 8439 5226
[email protected]
Karen Bartlett
Saltwater
Tel: +44 (0)1202 669244
[email protected]
About the Oceanology International Portfolio
Oceanology International – Connecting the global ocean technology, engineering and science communities
Oceanology International (Oi) is the global forum where the ocean industry, academia and government connect to discover innovative solutions from the ocean technology and marine science communities to improve strategies for exploring, protecting and sustainably operating in the world’s oceans and waterways. Held at ExCeL London, Oi brings together ocean professionals, facilitates ocean connections and showcases ocean innovation and technology.
www.oceanologyinternational.com
Oi exhibition and conference incorporates various events and features, including:
- COAST - The Coastal and Shallow Water Zone
New for 2026, COAST at Oceanology International offers exhibitors a unique platform to showcase their solutions, technologies, and expertise to a highly targeted and engaged audience from across the global coastal and shallow water community.
- Conference Program – Diving deep into the realm of ocean science and marine technology
Featuring a compelling line-up of industry-leading speakers, the full strategic Oi Conference Program encompasses a diverse range of Technical Sessions and Ocean Futures-focused content across different conference locations. World-class scientists, thought leaders and innovators in the vanguard of the global ocean technology community will converge to bring insightful and original content.
- Ocean Futures Theatre – Meeting future ocean technology needs
Thought leaders from industry, academia and government come together to discuss meeting future ocean technology needs in line with market developments and new ocean enterprise strategies. Held in the keynote Ocean Futures Theatre within Oi, it features panel discussions and strategic debates on topics including Transitioning the Ocean Economy, Sustainable Offshore Operations, BlueTech Investment and Future Talent/Careers.
- Dockside Demonstrations
Oceanology International’s dockside activity is a hallmark feature of the event, offering visitors live, in-water demonstrations of the latest ocean technology and equipment. Attendees have the unique opportunity to see cutting-edge remotely operated vehicles (ROVs), autonomous systems, sonar, imaging, and hydrographic survey tools in real-world action, guided by experts. These demonstrations take place at the Royal Victoria Dock, where multiple brands and vessels showcase novel capabilities—allowing participants to closely observe technological innovations and interact with operators, all with the goal of experiencing emerging solutions for marine and subsea applications firsthand.
About RX
RX is a global leader in events and exhibitions, leveraging industry expertise, data, and technology to build businesses for individuals, communities, and organisations. With a presence in 25 countries across 42 industry sectors, RX hosts approximately 350 events annually. RX is committed to creating an inclusive work environment for all our people. RX empowers businesses to thrive by leveraging data-driven insights and digital solutions. RX is part of RELX, a global provider of information-based analytics and decision tools for professional and business customers.
For more information, visit www.rxglobal.com.
About RELX
RELX is a global provider of information-based analytics and decision tools for professional and business customers. RELX serves customers in more than 180 countries and has offices in about 40 countries. It employs more than 36,000 people over 40% of whom are in North America. The shares of RELX PLC, the parent company, are traded on the London, Amsterdam and New York stock exchanges using the following ticker symbols: London: REL; Amsterdam: REN; New York: RELX.
*Note: Current market capitalisation can be found at https://www.relx.com/investor.