A small Belgian fishing fleet is using onboard sensors to tackle a problem that runs through sustainable fishing: we don’t know enough about what happens at sea. Working with scientists, fishers are collecting detailed information about their catches, fuel use, and fishing activity to make fisheries management more responsive to a changing ocean.

For those of us who care about the sea, better evidence is something worth getting behind. But understanding why these smart boats matter starts with the gaps in the system they’re trying to improve.

Key Takeaways

• Belgium’s VISTools project connects instruments on existing fishing boats, collecting detailed data without requiring an entirely new fleet.
• Manual catch records, daily totals and limited observer coverage leave scientists with an incomplete picture of fishing activity.
• Fishers can use their own data to compare catches, fishing patterns and fuel costs, whilst scientists gain more detailed information.
• Fleet data and wider environmental databases could support digital models that help predict changes and guide decisions.
• A regenerative fishery remains the ambition. The next test is whether better information and collaboration can support more sustainable fishing in practice.

A changing ocean is putting fishing under pressure

We’ve been talking about overfishing for years. The difference is that the ocean itself is changing, and the industry is trying to operate within a system that won’t sit still.

Warming seas are shifting where fish live. Some species are declining, whilst others are appearing in places where fishers haven’t encountered them before. Meanwhile, industrial fishing can deplete the species we depend on and work its way down the food web.

The pressure doesn’t stop underwater. Rising fuel costs make fishing more expensive, plastic pollution adds another burden at sea, and coastal communities are caught in the middle.

Environmental pressure. Economic pressure. Social pressure. All bearing down on the same boats and the people working them.

That matters because a fisheries system has to account for more than the quantity of fish landed. It also has to respond to changing ecosystems and keep the communities that depend on them involved. Those things are connected, however neatly we might separate them on paper.

Fishing rules have changed, but management needs to catch up

Hans Polet, a fisheries scientist with more than three decades of experience and scientific director for fisheries at ILVO in Belgium, describes how much management has changed.

Around 50 years before the interview, fishers had far greater freedom over how they fished and how much they caught. Overfishing and destruction made stronger controls necessary. Fleet reductions, mesh-size requirements and quotas took decades to establish.

Those changes mattered. Hans’s criticism is that EU fisheries management has encouraged innovation within fishing without changing its own approach enough.

“That initial drive to regulate and to control and to enforce has not really changed.”

Adding another regulation can only take us so far if the system underneath it remains slow and poorly informed.

The transition is described through the X curve, a model of systemic change. As an established system begins to break down, a more adaptable one can develop alongside it. There is an awkward period when the old arrangements still function, but their weaknesses are becoming harder to ignore.

Fishing is in that messy middle. VISTools is an attempt to build something more useful within it.

The blind spots in fisheries data

Good scientific advice depends on good information. Yet some of the basic questions about fishing activity remain surprisingly difficult to answer.

A boat’s route doesn’t tell us where its fish were caught

Much onboard catch information is still entered manually into logbooks. That leaves room for ordinary mistakes and, where someone chooses to misreport, false figures too. It’s a weakness in the reporting system, rather than a reason to assume every fisher is dishonest.

There is also a mismatch between vessel tracking and catch records. We may know where a boat travelled, but a daily catch total doesn’t tell us what happened at each point along that route.

A vessel can cover around 200 kilometres in a day. Did its catch come aboard near Belgium in the morning or nearer the Netherlands later on? The daily figure alone can’t answer that.

Discards remain difficult to measure

Discards are fish thrown back into the sea. Understanding what gets returned is another gap in the picture.

In the system Hans describes, scientific observers accompany only about 1% of fishing trips. Their observations provide a snapshot, but leave most activity unseen.

There is another complication: people can behave differently when somebody is watching. An observed trip may therefore differ from an ordinary working trip, which raises further questions about how representative the information is.

A two-year delay leaves decisions behind the ocean

Even the information that gets collected takes a long time to reach the people making decisions.

Data must be checked, stored in databases and worked into scientific advice. Hans describes a process that can take around two years. Formal advice arrives in December, then informs fishing decisions for January.

The calendar moves neatly enough. The ecosystem doesn’t wait for it.

By the time that advice reaches a policymaker’s desk, fish distribution or environmental conditions may already have changed. Scientists are being asked to provide accurate guidance using information that is incomplete at collection and delayed in use.

That combination is the problem VISTools is trying to address: detail and speed, together. More observations are useful, but their value is limited if they arrive too late to guide the decisions they were collected for.

VISTools adds sensors to boats already working

The project begins with an ordinary fishing vessel. The sort that’s already earning its living at sea.

A small hardware box, called a concentrator, brings together information from instruments aboard the boat. Sensors fitted inside and outside the vessel supply a much more detailed record of its activity.

ILVO’s explanation of VISTools describes inputs including GPS position, fuel consumption, catch weight and measurements associated with the fishing gear, such as winch force. Bringing those measurements together helps describe what happens haul by haul and trip by trip.

There is something encouragingly practical about that. The work uses boats already in the fleet, with equipment added to make their activity more visible.

For scientists, it creates a closer view of fishing effort and catches. For fishers, it puts information about their own working patterns within reach. Both have a reason to make the system useful.

Seeing what a catch actually earns

One of the project’s starting points was a fisher called Pedro arriving in Hans’s office with a laptop.

He showed Hans a map displaying where his vessel had fished and how much it had caught. The information was already useful to the person working the boat. The opportunity was to develop that further, together.

The team created sea maps and heat maps that let fishers examine where catches were strongest. They could compare day and night fishing, look at differences between species and start analysing the patterns within their own fishery.

Then fuel consumption went into the picture.

A catch has a gross value, but getting it aboard costs money. Adding fuel data helps fishers understand the net value more clearly, rather than judging an area only by how much fish it produces.

That’s a meaningful distinction when fuel costs are putting livelihoods under strain. It also gives scientists information about the relationship between fishing activity, catches and the effort required to obtain them.

The same data becomes useful on both sides of the conversation.

Collaboration is doing as much work as the technology

Hans is fairly blunt about the technical side. Collecting data isn’t rocket science.

The bigger achievement is getting fishers and scientists working together around information they both want to understand.

VISTools grew through direct collaboration, starting with practical interests rather than another instruction handed down from above. ILVO describes this as a living-lab approach: developing and testing the system with fishers under real working conditions.

That changes the relationship. Fishers help shape a tool that supports their work, whilst scientists gain access to information that has been difficult to collect at sufficient detail.

At the time of recording, the system was operational on 37 vessels in the Belgian fleet. That figure describes adoption of the monitoring system, rather than proof of a completed transition to sustainable fishing.

Still, it is a substantial part of the story. Equipment can collect measurements once it’s installed. Getting people to work together, share information and keep improving the system takes a different kind of effort.

For us, that cooperation is one of the most convincing parts of the project.

What sensors, cameras and eDNA could reveal

A more detailed view of fishing could help answer questions that broad catch totals leave open.

Scientists want to understand when fish are more abundant during the year, which areas may need time to recover, and how different uses of fishing gear relate to environmental impacts. The sensors give them a better basis for examining those connections.

Other tools could add further detail, although their stage of development matters.

Cameras could improve catch identification

AI-powered cameras are being developed to scan and identify fish on deck. The aim is to add another layer of evidence about what has actually been caught.

That could strengthen catch registration, but it shouldn’t be confused with a finished system already identifying every fish across the fleet. The camera and AI work is still being developed and tested.

Water samples could reveal nearby species

The team is also exploring environmental DNA, or eDNA. Analysing water for genetic material could help detect species nearby.

That offers a different kind of information from recording what comes aboard a vessel. Combined with catch records and other observations, it could help build a fuller picture of the surrounding ecosystem.

Again, this is work being considered and tested, rather than an established capability on every participating boat.

Building digital models of the fishery and the ocean

One boat gives us a detailed view of one fishing operation. Collecting information across a fleet makes it possible to examine activity over a much wider area.

Hans describes combining vessel information with databases developed by the EU. Together, these feed the VISTools model and support a digital representation of the fishing vessel and the fishery.

A digital twin is a model that draws on real-world information to describe a system and help predict how it might behave. Here, the aim is to describe vessel and fleet activity in real time and produce useful information for fishers, scientists, managers and other people using the sea.

The wider ambition reaches towards a digital twin of the ocean. Such models could help scientists examine shifting ecosystems, fish movements and the effects of climate change. They could also help evaluate the likely consequences of decisions before those decisions are put into practice.

That ambition needs a clear boundary. A working onboard monitoring system isn’t the same thing as a complete, reliable model of the ocean.

Hans’s point is that complex models are necessary because the planet is difficult to understand. Their usefulness still depends on the quality of the information going into them. The data gaps don’t disappear because the model becomes more sophisticated.

Making ecosystem-based management useful at sea

The ecosystem approach means understanding how the parts connect, rather than managing each fish stock in isolation.

It has been a recognised ambition, but putting it into practice requires information detailed enough, timely enough and trusted enough to guide decisions. Those requirements have been difficult to meet.

VISTools is intended to help close that gap. Better information could improve scientific advice and give fishers useful guidance about vulnerable species, areas to avoid and places where fish are concentrated.

The questions are practical. Where are threatened species? Which grounds should be left alone? What should a vessel avoid?

Involving the fishing industry in those decisions is part of the sustainability work itself. Fishers need information they can act on, alongside scientists who can interpret it and managers who can respond.

The proposed next step is a pilot project to test that wider approach in practice. The sensors provide a foundation. Whether that foundation leads to better management and more sustainable fishing is what the pilot needs to establish.

Frequently Asked Questions

Has VISTools already created a regenerative fishery?

No such result has been demonstrated here. Regenerative fishing is the ambition, whilst the established achievement is collecting more detailed information with participating fishers. Testing how that information supports management and sustainability is the next stage.

Would this approach mean getting rid of fishing regulations?

Hans doesn’t propose abandoning regulation. He explains why controls were needed to address overfishing, then questions whether the same management approach is adaptable enough for changing conditions. The argument is for better-informed management that includes the fishing industry.

Could the Belgian project become a model elsewhere?

That is a possibility if the proposed pilot succeeds. The project shows how a small group can begin changing working practices within an existing fleet, but it doesn’t establish that the same approach will work everywhere.

Where can we hear Hans explain the work in more detail?

The full podcast interview with Hans goes further into the project’s thinking and approach. There is also an audio version of Creators For Climate for listening away from the screen.

Who supported the film about the project?

The UN Ocean Decade helped fund the Creators For Climate film and bring the work to a wider audience. VLIZ is also credited as a supporter.

Better fishing needs evidence people can use

The strongest part of this work is that fishers and scientists are building a clearer picture together. Existing boats are supplying information that can help people understand catches, costs and pressure on the sea.

A regenerative fishing industry remains an ambition. The more immediate test is whether shared evidence can support better decisions on the water and in fisheries management.

That’s a concrete place to start: understand what is happening at sea, then use that understanding with the people whose livelihoods depend on it.