Return of the giants: Why bluefin tuna are back in Cornish waters
These magnificent ocean predators, some weighing over 600lb, have returned to Cornish waters for their annual summer feeding season, creating one of the country's most spectacular marine wildlife events.
Once commercially extinct in these waters due to overfishing, their reappearance signals improving ocean health and successful conservation efforts.
Despite their dramatic return, scientists still don't fully understand what's driving these powerful fish back to our waters.
Dr Tom Horton from the Centre for Ecology and Conservation at Exeter's Penryn Campus in Cornwall is leading research to unlock this mystery.
He explained: "Bluefin tuna come here to feed each year on smaller fish, but the reality is that we don't really know exactly what they're eating.
"This knowledge gap matters because if their prey populations decline, the bluefin may well migrate elsewhere."
Understanding the tuna's diet could be crucial to ensuring their continued recovery.
Commercial bluefin tuna fishermen working off Devon and Cornwall are partnering with researchers to analyse stomach contents from caught fish.
These predators play a vital role in marine ecosystems. Marine biologist for the Cornwall Wildlife Trust, Matt Slater, explained that tuna feed primarily on sardines, and with abundant sardine populations in our waters, the tuna's feeding habits are unlikely to conflict with commercial fishing interests.
Chris Gill, one of the commercial fishermen involved, sees the partnership as essential for the species' future.
He said: "It's great to be able to work with the team to make the most out of every bluefin tuna we catch.
"We're all invested in the comeback of bluefin tuna, and making sure there's enough food to keep them coming here is clearly important."
The tuna's return has generated excitement among conservationists who see it as evidence that marine protection efforts can work.
Dan Barrios-O'Neill from Cornwall Wildlife Trust describes their comeback as "a real sign of hope in a rapidly changing world".
However, questions remain about the sustainability of this recovery. Climate change is altering ocean temperatures and prey distributions, while fishing pressure on small fish that tuna depend on continues globally.
The research extends beyond simple curiosity about tuna diets. Scientists want to understand how these predators fit into the broader marine ecosystem and what their return means for other species.
Emily Theobald from the Marine Management Organisation emphasised the practical importance of this research, saying: "More science means more understanding, which means better ability for fisheries managers to manage effectively and sustainably."
The project is seeking crowdfunding support to complete this season's research. The research team plans to share their findings with policymakers and managers, potentially influencing how the UK protects both predators and their prey.
As Jonny Hughes from Blue Marine Foundation notes, incorporating predator needs into fisheries management represents an important evolution in ocean conservation.While these magnificent fish continue their summer visits to British waters, scientists are racing to unlock the secrets of their return.
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ITV News
3 days ago
- ITV News
Return of the giants: Why bluefin tuna are back in Cornish waters
Atlantic bluefin tuna are making a remarkable comeback in our seas - a spectacular annual event that marine biologists witness each summer, yet remains largely unknown to the public. These magnificent ocean predators, some weighing over 600lb, have returned to Cornish waters for their annual summer feeding season, creating one of the country's most spectacular marine wildlife events. Once commercially extinct in these waters due to overfishing, their reappearance signals improving ocean health and successful conservation efforts. Despite their dramatic return, scientists still don't fully understand what's driving these powerful fish back to our waters. Dr Tom Horton from the Centre for Ecology and Conservation at Exeter's Penryn Campus in Cornwall is leading research to unlock this mystery. He explained: "Bluefin tuna come here to feed each year on smaller fish, but the reality is that we don't really know exactly what they're eating. "This knowledge gap matters because if their prey populations decline, the bluefin may well migrate elsewhere." Understanding the tuna's diet could be crucial to ensuring their continued recovery. Commercial bluefin tuna fishermen working off Devon and Cornwall are partnering with researchers to analyse stomach contents from caught fish. These predators play a vital role in marine ecosystems. Marine biologist for the Cornwall Wildlife Trust, Matt Slater, explained that tuna feed primarily on sardines, and with abundant sardine populations in our waters, the tuna's feeding habits are unlikely to conflict with commercial fishing interests. Chris Gill, one of the commercial fishermen involved, sees the partnership as essential for the species' future. He said: "It's great to be able to work with the team to make the most out of every bluefin tuna we catch. "We're all invested in the comeback of bluefin tuna, and making sure there's enough food to keep them coming here is clearly important." The tuna's return has generated excitement among conservationists who see it as evidence that marine protection efforts can work. Dan Barrios-O'Neill from Cornwall Wildlife Trust describes their comeback as "a real sign of hope in a rapidly changing world". However, questions remain about the sustainability of this recovery. Climate change is altering ocean temperatures and prey distributions, while fishing pressure on small fish that tuna depend on continues globally. The research extends beyond simple curiosity about tuna diets. Scientists want to understand how these predators fit into the broader marine ecosystem and what their return means for other species. Emily Theobald from the Marine Management Organisation emphasised the practical importance of this research, saying: "More science means more understanding, which means better ability for fisheries managers to manage effectively and sustainably." The project is seeking crowdfunding support to complete this season's research. The research team plans to share their findings with policymakers and managers, potentially influencing how the UK protects both predators and their prey. As Jonny Hughes from Blue Marine Foundation notes, incorporating predator needs into fisheries management represents an important evolution in ocean these magnificent fish continue their summer visits to British waters, scientists are racing to unlock the secrets of their return.
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