We all want healthy seas

We all want healthy seas

Dan Barrios-O'Neill, Head of Marine Conservation at Cornwall Wildlife Trust, explores the topic of our 2025 panel discussion, Can we have healthy seas and productive fisheries?

Our government claims to be “mission-driven” through five key objectives to rebuild Britain. Despite the notable absence of nature from this mission list, a huge constituency of individuals, communities, and organisations across the country are very much on a mission to protect 30% of land and sea by 2030.  

The success of the salty bit of this mission depends heavily on how we manage fisheries, as overfishing has a greater impact on marine biodiversity than pollution, or even climate change.

Because fishing is the issue in our seas, conservation and fisheries interests are typically—often mistakenly—seen as conflicting. And now it feels like we’re rapidly approaching a tipping point. A real moment of change. This year we’ve seen a high profile battle between fisheries interests and conservation, with the UK defending a sandeel fishing ban in the North Sea.  And the release of Ocean, Sir David Attenborough’s last, and hardest-hitting documentary, has exposed many to the devastating impacts of bottom trawling for the first time.  

In Cornwall, figuring out how to deliver for nature and fisheries really matters, because the sea underpins so much of what we value: Our culture, our history, our economy, and our wellbeing. We have more coastline than any other English county, busy fishing ports landing tonnes of catch daily, internationally important marine habitats, and a critical mass of marine conservationists, enthusiasts, and water users. There has never been a more important time to ask the question: “Can we have healthy seas and productive fisheries?” and I believe Cornwall is one of the most important places to be asking it.  

Crawfish by Jan Volney

On the 14th of May, Cornwall Wildlife Trust did exactly this by convening a panel of conservationists, scientists, and fishers to discuss this topic in front of a live audience.  

We worked hard to deliver balance; to hear a range of viewpoints, not just those of the conservation consensus. No approach is perfect, and some disagreements were inevitable. But my overwhelming sense of the evening’s conversation was that everyone—panellists and audience alike—left with a deeper understanding of the issues, with more appreciation for other views, and with more understanding of the complexities of delivering for nature and fisheries in Cornwall. Modest but important progress in my book. 

Panellists discuss the issue of healthy seas at cornwall wildlife trust 2025 panel discussion

The panellists covered a lot of ground, deftly chaired by BBC Radio Cornwall’s Julia Skentelbery. I recommend watching the recording if you can. With such a big topic, we could have continued the discussion for much longer—and there was clearly a desire for this from our very engaged audience. Here are my top three essential take-homes from the discussion:   

1. The question is not whether we need marine protection but how much. In the wake of the Ocean documentary, much has been made of the prospect of towed bottom gear bans in our Marine Protected Areas (MPAs). However, as panellist Prof. Callum Roberts (University of Exeter) pointed out, areas with partial restrictions—i.e. areas that are not full No Take Zones (NTZs)—do a lot of heavy lifting to support biodiversity, and to drive the astonishing spill-over effects that demonstrably benefit fisheries. The evidence for NTZs  is complex, but in my view clear enough: in sum, they work. The debate is now about how much outright protection is needed, as opposed to more effective fisheries management.  

Panellist Gus Caslake of Seafish made a good case for the effective management we do have, particularly for our Cornish Sardines, which we recommend through our Cornwall Good Seafood Guide. At the same time, Gus was pretty clear that fishers aren’t against NTZs by default, and in fact many fishers supported the establishment of the UK’s first NTZ around Lundy in 2003. My firm belief is that we need to deliver more of this kind of protection, and better management, with support from fishers. 

2. Food security and livelihoods matter. Panellist Jason Pascoe, a Cornish fisher, expressed dismay at the way bottom trawling was portrayed in Ocean, pointing out that the scale and methods typically used in Cornwall are not comparable. The National Federation of Fishermen's Organisations is similarly dismayed. My position is that, while bycatch rates in Cornwall can be much lower than implied in Ocean, all bottom gears cause some degree of damage. I think that Seafish’s own trial footage in Looe shows this. But the science is clear that the gear used and habitats fished do matter a lot and, in the case of our traditional oyster fishery, the impacts are vanishingly small by comparison.  

I believe it is entirely appropriate for conservation organisations to support the livelihoods of small-scale inshore fishers like Jason, who fish sustainably, and have done for years. Support for local food production is important for climate, for nature, and for food security: if we push to protect new areas without considering how our food consumption is offshored, with potentially net-negative environmental impacts, then benefits to nature could be a local mirage (this is called biodiversity leakage). The relatively small quantities of fish we currently consume does not invalidate this argument. As Gus pointed out, most of the fish we land locally in Cornwall is exported, while most of the fish we consume in Cornwall is imported. This is not a recipe for food security, and there’s clearly scope for more sustainable local consumption. Indeed, panellist Matt Slater of Cornwall Wildlife Trust has been a driving force behind the Cornwall Good Seafood Guide for a decade now. CGSG is all about supporting the most sustainable seafood, and our local fishing industry. It represents unambiguous and sustained support from Cornwall Wildlife Trust for sustainable local consumption.  

3. Baselines have been shifting from well beyond the living memory of anyone alive today. To understand what healthy seas could really look like we need to have a frame of reference. The problem is that people have fished for thousands of years, and fishing has likely been driving sustained ecological changes for at least a couple of centuries. In 1883, the biologist Thomas Huxley famously said that "All the great sea-fisheries are inexhaustible; that is to say, nothing we do seriously affects the number of fish" and yet, in the same speech, he noted a decline in oyster populations. Today, the evidence shows that our oyster populations have collapsed and many of our “great sea fisheries” are struggling, at best. Despite incredible advances in fishing technology, Callum’s research shows that fish landings per unit of effort have declined by an astonishing 94% in little more than a century.  

The important point is this: no-one alive today—no fishers, no scientists, no conservationists, no-one—has any lived experience of what healthy seas really look like in the UK. It is a mind-bending conceptual leap to even begin to imagine the abundance we once had. Here, stories carry more weight than statistics, and the few signs of local recovery we do see are deeply significant. 

Despite the many challenges we face, I came away from the panel discussion feeling energised. We certainly don’t agree on everything, but most disagreements seem to be about the path, rather than the destination: we all want healthy seas. In other words, conservationists and fishers have a lot more in common than many would have you believe.  

The optimism I feel is underpinned by the realisation that everyone can do something. The public can make more diverse and sustainable choices that support local livelihoods, scientists and conservationists can work closely with fishers to figure out the way forward, and we can all engage on multiple political and social fronts to work for a better future for our seas, and for all the communities that depend on them. 

Mass gathering of spider crabs, Image by Alexander Mustard/2020VISION

Mass gathering of spider crabs, Image by Alexander Mustard/2020VISION

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