The government needs to urgently end polluting tax breaks for the UK fishing fleet that threaten to “empty the ocean of fish”, say conservationists, after a first-of-its kind study reveals diesel subsidies to be worth up to £1.8bn a decade. Without the tax subsidies, largely provided to the most fuel-intensive section of the fleet, many sectors would be unprofitable, according to the analysis by government environmental advisers. Globally, fuel subsidies to the fishing industry were estimated at $8bn (£6.3bn) in 2018, and represented a third of all harmful fishing subsidies, the authors said, adding that they were a key factor in the widespread depletion of fish populations, more than a third of which are overfished. Fuel-tax concessions for the UK industry amounted to £150m-£180m a year, from 2009 to 2019, according to the analysis of industry data, which was published in the journal Marine Policy last autumn. They amount to between 15% and 18% of the industry’s income, which was worth £1bn last year. This tax relief benefits the most fuel-intensive, climate change gas-emitting and industrial fishing methods, such as trawling and dredging, acting as a disincentive to developing a more fuel-efficient and carbon-smart industry, campaigners said. “The government has never admitted that it was dishing out anything like this much in tax breaks to the fishing industry. This indicates that, until this paper was published, the Treasury simply did not know it was doing so,” said Charles Clover, author and co-founder of the Blue Marine Foundation. “We will not be alone in calling for these unjustifiable and idiotic subsidies to be phased out as soon as possible.” Daniel Skerritt, one of the paper’s co-authors and a senior analyst at the not-for-profit environmental group Oceana Canada, said: “What struck me was not just the value of the fuel-tax concession, but how much certain fleet segments need it to survive. This supports the kind of fishing that burns the most fuel, when we ought to be looking at it becoming more fuel efficient.” Beam trawlers, vessels dredging for scallops and those trawling for North Sea nephrops (langoustines or scampi) would all be unprofitable without fuel-tax concessions, researchers found. Overall, the fishing sector was decades behind other industries in this area, Skerritt said. A failure to end the tax breaks could cause problems for the UK, which in December pledged to ratify the World Trade Organization’s unprecedented agreement to end fishing subsidies and also to support the second stage of WTO negotiations next month to end the most harmful subsidies, including fuel subsidies. Removing the tax concession overnight would spell “disaster” for the industry, Skerritt acknowledged, but he suggested a phased approach. “I don’t want to see the end of the fishing industry,” he said. “But I also don’t want a fishing industry that’s using excessive amounts of fuel or being propped up by taxpayers’ money.” A paper in the journal Nature in 2021 suggested that bottom trawling, a widespread fishing practice where heavy nets are dragged along the sea bed, releases a gigaton of CO2 annually – as much carbon dioxide as the entire aviation industry every year. Prof Rashid Sumaila, another co-author on the paper, and fisheries economist at the Institute for the Oceans and Fisheries, University of British Columbia, said: “I am fine with getting money into the fishing communities in the UK, but please don’t let public funds be used to empty the ocean of the fish that fishers and fishing communities depend on for their livelihoods, food and nutritional security.” The study’s authors said that keeping otherwise unprofitable segments of the fleet viable could arguably support food and livelihood security, and generate income, for potentially vulnerable communities. But they added: “However, given that much of the catch is currently exported and is not consumed by the domestic market, the food security argument is weaker than first seems.” A spokesperson for Seafish, a public body supporting the UK fishing industry, said any loss of this subsidy would see further increases in food prices for everyone. “If you remove the exemption from fishing, it could make our domestic fishing fleet less competitive against imported fish coming in on shipping containers, which would still be exempt.” Agriculture was also exempt, the spokesperson said, adding: “There’s research and investment going into new technologies and exploring alternative fuel sources, but it will take more investment and time to find viable solutions.” A government spokesperson said: “We are fully committed to sustainable fishing, which is why we recently signed a global agreement to stop harmful subsidies that contribute to overfishing. We are also providing an additional £100m to help UK fisheries to be more sustainable and since leaving the EU we are using our new powers to implement more sustainable fishing policies.”