Three easy steps the UK could take now to turn around the destruction off our marine life

An easy question: imagine we could offer the world’s governments a policy that would help reverse decades of damage to the ocean, restore marine life, restock the world’s fisheries, help some of the world’s poorest communities and save money. Should the world adopt it?

The policy – allowing the ocean to heal itself – is real, and proven to work. Humanity has done grievous damage to life in the ocean, at enormous cost to ourselves and the planet. We know that, given the chance, it will recover at speed to the benefit of everyone whose lives depend on the sea. We know that the changes needed to bring about this recovery are eminently doable, and could mostly be brought about by governments ending costly subsidies of uneconomic and destructive fishing practices. So the harder question is: given we know all this, why aren’t we doing it? That was the question at the third UN ocean conference in Nice last week.

The answer comes down to the tragedy of the commons – the dilemma in economics where rational actors will deplete a shared resource for individual gain to the detriment of everyone. This is exactly what has been happening with the ocean. For decades, because it was so vast and so much of it belonged to no one, we've treated it as if it were an infinite resource, able to provide us with food and absorb our waste without limits.

It turns out that the ocean has very real limits, and we are well past them.

Bottom trawling is the perfect example of a tragedy of the commons. It involves dragging heavy nets across the ocean floor. It is an efficient method for catching large volumes of fish and shrimp quickly, make a modest amount of income for a relatively tiny number of companies, though only on the basis of considerable subsidies. The damage it causes is unimaginably greater. The ratio of individual benefit versus collective loss is breathtaking.

Habitats – many of which are essential breeding or foraging grounds for marine species – are literally crushed. Fragile ecosystems such as coral reefs, sponge beds and seagrass meadows are destroyed. The impact is catastrophic, from making fisheries non-viable to releasing vast quantities of carbon through disturbing the sediment.

Research conducted by the Zoological Society of London’s scientists on deep-sea trawling around the English coast has revealed huge disruption caused to the natural state and productivity of these habitats – equating it to the level of damage caused by clearing a forest.

The only solution to the tragedy of the commons is to change the rules. And there are three easy changes the UK government could make right now, at little cost.

First, it should build on the legislation announced last week and ratify the high seas treaty. Two-thirds of the ocean is classed as international waters – the high seas. They get almost no protection, a victim of the fact that if something belongs to everyone, it is like it belongs to no one.

The treaty creates a legal framework to protect marine biodiversity in international waters. It will allow for the creation of marine protected areas (MPAs), enforce international cooperation and regulation, and require environmental impact assessments for activities that may harm marine biodiversity. It needs 60 countries to ratify it before it comes into force. At the start of the week, 31 countries had done so. By the end of the week, it was up to 50.

Given Britain’s maritime heritage and our aspirations to lead the world in protecting nature, we should have been the first to ratify. Yet the UK is not among the first 50. But credit where it is due – the government did announce this week that it was allocating the parliamentary time needed for ratification by the end of the year, a welcome step forward.

Second, the UK can make an outsized contribution to the health of the ocean by committing to continue protecting the seas around our overseas territories. These dots around the world make the UK an ocean superpower, responsible for 6.8 million sq km of ocean (and one-third of the world’s penguins, more than any other country). Thanks to the UK’s blue belt programme, nine of the overseas territories have established large MPAs, some of the biggest in the world, to protect vulnerable ecosystems and species.

This single programme has allowed the UK to meet its commitment to protect at least 30% of its waters by 2030. The blue belt programme costs £8m a year, to protect an area 1.5 times the size of India, making it about the best value-for-money conservation in the world. The government has yet to commit long-term funding beyond 2025, which risks making these vital ocean sanctuaries ineffectual.

Third, and closer to home, the government could ban bottom trawling across all the UK’s marine protected areas. It took a step forward this week with Steve Reed’s welcome proposal to almost triple the area in which bottom trawling is banned from the current 18,000 sq km to 48,000 sq km. But that would still leave 290,000 sq km of “protected” sea in which bottom trawling will still be allowed. As things stand, that is only 5% of the total UK MPA area that is currently protected from bottom trawling, with a proposal to increase it to 14%. And it is frankly bizarre that this ultra-destructive fishing technique is still allowed in any of what the government claims are protected parts of our seas, particularly given what we now know both of the devastation it causes and of the speed at which the ocean can recover when it is allowed to do so.

With these three modest steps, the UK could go from laggard to leader, and ensure that we are doing our part in allowing the world’s ocean to recover. The really good news is that we know it will recover, if we let it.

Matthew Gould is CEO of ZSL (Zoological Society of London) and Prof Heather Koldewey is ZSL Head of Ocean Conservation