Damaging fishing is taking place in almost all the UK’s offshore protected areas that were created to conserve seabed habitats, a report warns.
The Marine Conservation Society (MCS) warns that bottom trawling, in which heavy nets are dragged across the seabed to collect fish and shellfish, destroys natural habitats and releases carbon.
It is calling for a ban on bottom trawling in marine-protected areas to conserve and build up carbon stores as part of efforts to curb climate change, and to help habitats and wildlife recover.
Allowing bottom trawling to take place in protected sites is the equivalent of bulldozing national parks on land, the charity said.
A report by scientists at the MCS found that all but one of the offshore marine protected areas designated to protect the seabed experienced bottom trawling and dredging between 2015 and 2018.
During that time, sandbanks and reefs which were supposed to be protected saw at least 89,894 hours of fishing by vessels using gear that can damage the seabed.
The UK has a network of 358 marine-protected areas, including 70 offshore sites which are intended to protect the seabed, the report said.
But only 5% of all UK marine-protected areas currently ban bottom trawling, and the practice is taking place in 98% of the UK’s offshore protected areas designated to protect vital seabed habitats, the charity warned.
As well as destroying anemones, corals, sponges, fish and crustaceans, bottom trawling releases carbon from the muddy and sandy sediments into the ocean, and potentially the atmosphere where it adds to climate change.
The release of carbon by bottom trawling across the UK continental shelf between 2016 and 2040 could cost up to £9 billion to mitigate through cutting emissions in other areas of the economy.
Continued disturbance of the carbon stored in offshore marine protected areas alone could cost nearly £1 billion over the next 25 years, the report estimates.
A ban on bottom trawling in protected sites has shown to be effective in the UK and around the world, with a boost to wildlife, which spills over into nearby waters to increase fishing catches outside the conservation zones.
Carbon stores are left undisturbed, and are able to build back up as new life establishes itself on the seabed, the report said.
Dr Jean-Luc Solandt, principal specialist in marine-protected areas at the Marine Conservation Society, said: “While bottom trawling is still allowed we will continue to release more carbon from the seafloor and prevent complex carbon-storing habitats from recovering.
“In order to battle the climate emergency there has to be limits on where fishing of this kind can take place.”
And he said: “Without a ban on this form of fishing, these areas of our seas simply aren’t recovering and we’re missing a crucial opportunity to combat climate change and ensure there are indeed plenty more fish in the sea.”
An Environment Department (Defra) spokesperson said: “As an independent coastal state, the UK can now review which vessels can access and fish our waters.
“All boats must abide by our rules around sustainability and protection of our marine protected areas (MPAs).
“Last year, the Government commissioned a review of how we protect our MPAs and we are carefully considering whether there is a case for increased protections for these areas.”