Professor Callum Roberts, a co-author of the study and marine conservation expert from the Centre for Ecology and Conservation at Exeter’s Penryn Campus, noted the alarming rate at which vital species have disappeared from UK waters
Ditching fish and chips might not just benefit waistlines — it could help save the planet. Scientists are calling for a rethink of Britain’s beloved dish, warning that key species used in the national staple, including Atlantic cod, skate, black seabream and red gurnard, play a critical role in maintaining the health of the seabed and, by extension, the climate.
The call follows findings from the Convex Seascape Survey, a major study that explored the role of fish in a little-known but crucial process called bioturbation — the stirring and mixing of sea floor sediments by living organisms. While invertebrates like worms and crustaceans are already recognised for their role in bioturbation, the new research sheds light on the significant impact that fish have on seabed ecology.
“Bioturbation is very important for how the seabed takes up and stores organic carbon, so the process is vital to our understanding of how the ocean absorbs greenhouse gases to slow the rate of climate change,” said Mara Fischer, the study’s lead researcher and a PhD student at the University of Exeter. “Ocean sediments are the world’s largest reservoir of organic carbon – so what happens on the seabed matters for our climate.”
The study analysed 185 species of demersal (bottom-dwelling) fish and discovered that 120 of these species contribute significantly to bioturbation — the majority of which are routinely caught and removed by commercial fishing operations. This loss, researchers warn, could be reshaping marine ecosystems in ways that are still poorly understood.
“This is the first attempt to quantify the bioturbation impact of fish, and it shows they play a significant, widespread role,” Fischer added. The researchers highlighted that fish influence seabed chemistry and carbon cycling not only by disturbing sediment as they feed or move, but also through their waste and carcasses.
Professor Callum Roberts, a co-author of the study and marine conservation expert from the Centre for Ecology and Conservation at Exeter’s Penryn Campus, noted the alarming rate at which vital species have disappeared from UK waters. “Many of the largest and most powerful diggers and disturbers of seabed sediments, like giant skates, halibut and cod, have been so overfished they have all but vanished from our seas,” he said. “These losses translate into big, but still uncertain, changes in the way seabed ecosystems work.”
While the nation’s affection for fish and chips runs deep, scientists say there’s an urgent need to reconsider the environmental cost of our dining choices. The findings suggest that our collective appetite may be digging up more than just dinner — it could be unearthing an overlooked climate threat. With fisheries management already under scrutiny for its ecological impact, researchers say protecting key fish species could be as important for the planet as cutting emissions or planting trees. For the health of the ocean and the fight against climate change, a battered cod might just be a habit the world can no longer afford.
