‘A sham’: UK offshore marine protected areas suffer over 20,000 hours suspected bottom trawling
The UK’s offshore marine protected areas (MPAs) suffered over 20,000 hours of suspected bottom-trawl fishing last year, which would score tracks on the sea bed reaching over eight times around the UK, a new Oceana report has revealed. Bottom trawling is permitted in 90% of UK MPAs, making the network little more than a sham that does not do enough to protect nature, says Oceana.
Only 38 of the UK’s 377 MPAs are fully protected by law from destructive bottom trawling, Oceana UK’s report, The Trawled Truth, states, and satellite tracking data shows that offshore MPAs alone suffered over 20,600 hours of suspected bottom trawling in 2024.
Bottom trawlers are large, fuel-intensive vessels that drag heavy metal gear and nets – often weighing several tonnes – across the seafloor, indiscriminately hoovering up sea life and effectively bulldozing marine habitats. Almost all seabed habitats around the UK are currently categorised as ‘poor status’, with bottom trawling identified as the main pressure.
The three most exploited MPAs were off the coast of Cornwall and Scotland and suffered a combined 8,597 hours of suspected bottom trawling. The Western Channel and Southwest Deeps (East) MPAs off Cornwall are home to wildlife ranging from cat sharks to cuckoo rays to threatened fan mussels. The West of Scotland MPA boasts delicate, slow-growing corals; orange roughy, which can live for 150 years; and spawning areas of the commercially important blue ling.
Alyx Elliott, Campaigns Director of Oceana UK, said: “Bottom trawling is devastating our seas. Across our ‘protected’ havens for nature, weighted nets are clear-felling the forests of the ocean and butchering our marine wildlife wholesale. The UK currently has the worst of all worlds: the illusion of protection masking ongoing destruction. Unless the government takes action, our marine protected areas will remain a sham. Last year, shadow Environment Secretary Steve Reed claimed that if elected he would act to stop this destruction – so what’s the delay? Our seas need more than empty promises.”
These results are an underestimation of the scale of the damage, says Oceana. Firstly, because the analysis excludes inshore MPAs, and secondly, Norwegian vessels could not be included due to a lack of information on their fishing gear.
Trawling ban boon
Banning trawling in MPAs would be a win-win-win for nature, small-scale fishers, and the taxpayer. The benefits for the fishing industry, tourism, climate regulation and other services provided by a healthy ocean worth a net gain of £2.57-3.5 billion over 20 years could be delivered by a ban in the UK’s offshore seabed MPAs alone, previous research has estimated.
A ban also has strong public backing: eight in ten UK adults think that bottom trawling should be banned in MPAs, polling carried out for Oceana showed, and 64% mistakenly believe that that is already the case.
Patchy protection
So far, the UK Government’s limited measures to manage bottom trawling in MPAs have centred around restrictions only for specific ‘features’, such as reefs. This isolates fragments of habitat and forestalls any real chance of regeneration and recovery, threatening the UK’s commitment to protecting 30% of land and sea by 2030.
Dr Emma Sheehan, Associate Professor of Marine Ecology, University of Plymouth, said: “Safeguarding marine protected areas from bottom trawling and dredging would have wide ranging and substantial benefits for society. It would help boost marine biodiversity and the abundance of commercial species inside and outside these areas, as well as helping to mitigate climate change. Banning trawling across the entirety of these sites, rather than for limited features, is especially important, since it would allow these ecosystems to rejuvenate, rather than maintaining the current poor condition.”
The value of protecting the entirety of each marine protected area should not be underestimated. Oceana’s report cites the example of Lyme Bay, England, where partial ‘features’ protection saw an increase in abundance of marine life of 15%, but in areas where the whole site was free of trawling, that figure was 95%. Whole-site bans are also three times cheaper to enforce according to Scottish Government estimates, the report highlights.
The UK Government had committed to introducing laws to protect MPAs from bottom trawling before the end of 2024, but this deadline has been missed, and no new date has been set.
ENDS
Notes for editors
- Read the embargoed report here.
- For more information or to arrange interviews with Oceana experts please contact media consultant Clare Sterling at claresterling@hotmail.com or mobile +44 (0)7808 725096.
- Other media assets including images, graphics and video available here.
- Oceana is asking the public to write to the Environment Secretary Steve Reed asking him to ban bottom trawling in all MPAs.
About the data
[1] This analysis focused on the UK’s 63 offshore benthic MPAs. These sites are located beyond 12 nautical miles from our coast, designated specifically for the importance of their seabed features.
For this analysis, Oceana used data from Global Fishing Watch, an independent non-profit founded by Oceana in partnership with Google and SkyTruth. Oceana identified satellite tracks within MPAs that indicated industrial fishing (based on Global Fishing Watch (GFW) algorithms, machine learning, and a random manual inspection of the data by the Oceana analyst team) and then narrowed the dataset down to vessels that were registered as carrying bottom trawl or dredging gear as at least one of their gear types. This matching process is external to GFW, since the information from GFW does not currently distinguish between “bottom” and “mid-water” trawlers.
GFW uses data about a vessel’s identity, type, location, speed, direction and more that is broadcast using the Automatic Identification System (AIS) and collected via satellites and terrestrial receivers. GFW analyses AIS data collected from vessels that its research has identified as known or possible commercial fishing vessels and applies a fishing presence algorithm to determine “apparent fishing activity” based on changes in vessel speed and direction. The algorithm classifies each AIS broadcast data point for these vessels as either apparently fishing or not fishing and shows the former on the GFW fishing activity heat map. AIS data as broadcast may vary in completeness, accuracy and quality. Also, data collection by satellite or terrestrial receivers may introduce errors through missing or inaccurate data.
GFW’s fishing presence algorithm is a best effort to mathematically identify “apparent fishing activity.” As a result, it is possible that some fishing activity is not identified as such by GFW; conversely, GFW may show apparent fishing activity where fishing is not actually taking place. For these reasons, GFW qualifies designations of vessel fishing activity, including synonyms of the term “fishing activity,” such as “fishing” or “fishing effort,” as “apparent,” rather than certain.
Any/all GFW information about “apparent fishing activity” should be considered an estimate and must be relied upon solely at your own risk. GFW is taking steps to make sure fishing activity designations are as accurate as possible. GFW fishing presence algorithms are developed and tested using actual fishing event data collected by observers, combined with expert analysis of vessel movement data resulting in the manual classification of thousands of known fishing events. GFW also collaborates extensively with academic researchers through its research program to share fishing activity classification data and automated classification techniques.
About Oceana UK – uk.oceana.org
Oceana UK is dedicated to ensuring UK seas get the protection they deserve. We use science-based campaigns, legal challenges and razor-sharp advocacy alongside creative storytelling to achieve measurable progress towards diverse and healthy UK waters, with ocean wildlife thriving alongside communities.
About Global Fishing Watch – globalfishingwatch.org
Global Fishing Watch, a provider of open data for use in this report, is an international nonprofit organisation dedicated to advancing ocean governance through increased transparency of human activity at sea. The views and opinions expressed in this report are those of the authors, which are not connected with or sponsored, endorsed, or granted official status by Global Fishing Watch. By creating and publicly sharing map visualisations, data, and analysis tools, Global Fishing Watch aims to enable scientific research and transform the way our ocean is managed. Global Fishing Watch’s public data was used in the production of this publication.