Restoring wildlife habitats in the UK could drive extinctions in other countries, according to a new study.
Experts have warned that ‘ringfencing’ certain areas for protection or restoration are shifting harmful land use to other parts of the world.
This could lead to an even steeper decline in the planet’s species, especially in countries such as Australia and Italy, they said.
And the damage from this ‘leakage’ could be five times greater than the local benefit to British diversity.
Researchers from over a dozen institutions worldwide – including the University of Cambridge – have come together to warn that this effect is largely neglected when discussing conservation efforts.
For their study they applied real-world food and biodiversity data to hypothetical conservation projects, including one in the UK.
They discovered that if 1,000km2 of arable farmland in the UK that produced wheat, barley and oilseed rape was reclaimed for nature, production of these products would be displaced to Australia, Germany, Italy and Ukraine.
As the UK has fewer species than these other countries, damage from ‘leakage’ could be five times greater than the local benefit to British diversity, they said.
Brazil is by far the largest exporter of soy in the world. Rewilding a sizeable area of Brazilian soybean farms would push production to nations such as Argentina and the US – an example of ‘biodiversity leak’. Pictured, soybean harvest on a farm in Londrina, Parana State, Brazil
One example of UK farmland being reclaimed for nature is the Knepp Estate in West Sussex (pictured), where white stalks are returning due to a rewilding project
While the UK is home to over 70,000 species of animal, plants, fungi and microorganisms, Australia supports nearly 600,000 native species.
The experts point out that even the UN’s landmark Global Biodiversity Framework – which aims for 30 per cent of the world’s land and seas to be conserved – makes no mention of the leakage issue.
‘As nations in temperate regions such as Europe conserve more land, the resulting shortfalls in food and wood production will have to be made up somewhere,’ said Professor Andrew Balmford, from Cambridge’s Department of Zoology.
‘Much of this is likely to happen in more biodiverse but often less well-regulated parts of the world, such as Africa and South America.
‘Areas of much greater importance for nature are likely to pay the price for conservation efforts in wealthy nations unless we work to fix this leak.’
The team argued that there should be much more caution taken when restoring natural habitats on currently productive farmland in less biodiverse parts of the world.
One place where this issue has already been seen in action is in the European Union, the researchers said, where forest cover has increased dramatically since the 1990s but an almost equal area of forest overseas – much of it in Indonesia and Brazil – has been cleared to provide exports for the EU.
‘At its worst, we could see some conservation actions cause net global harm by displacing production to regions which are much more significant for biodiversity,’ Professor Balmford added.
In Brazil, restoring soy-producing land will mean fewer soy exports from Brazil to other countries which might benefit nature as a whole. But in the UK, restoring land usually reserved for production of grain to feed the nation could mean more imports needed from abroad
The Gola Rainforest Project in Sierra Leone. This conservation project has limited leakage while slowing deforestation by supporting nearby farmers such as Mallo Samah to increase their yields and get higher prices for their cocoa.
He said there are several ways to tackle the problem – including targeting conservation to the most important places for nature.
Co-author Dr Fiona Sanderson, from the RSPB, works on reducing the impacts of cocoa production in Sierra Leone.
‘Without attention and action, there is a real risk that the biodiversity leak will undermine hard-won conservation efforts,’ she said.
The researchers did not name specific rewilding projects in the UK and stressed that their study is based on hypothetical scenarios.
However, one prominent example of UK farmland being reclaimed for nature is the Knepp Estate in West Sussex, where white stalks are returning due to a rewilding project.
At Knepp Estate, large areas of former arable fields have been allowed to revert to a wild state, with the introduction of native grazing animals like Exmoor ponies, red deer and pigs.
Owners of the Knepp Estate have previously said they simply couldn’t profit from clay-heavy soils – which were waterlogged in winter and concrete-hard in summer – and which put them in £1.5 million debt.
Meanwhile Strawberry Hill – a formerly farmed area in Bedfordshire – has been left fallow for many years, providing habitat for threatened bird species.
A wave of rewilding projects are also sweeping across Scotland, including Carrifran Wildwood and Bunloit Estate.
The White Stork Project, which is based at the Knepp Estate in West Sussex, has 25 home-grown storks which have chosen to spend the winter in the UK
The findings were published in Science – one of the journals that will feature at the American Association for the Advancement of Science (AAAS) conference in Boston this week.
Commenting on the study Richard Bunting, spokesman for Rewilding Britain, said: ‘There is no need for Britain to lose farmland used for growing food as we tackle the nature and climate emergencies and benefit people through rewilding.
‘But by recognising rewilding as a highly productive use of land, we will all have the chance of a more secure and prosperous future.
‘It’s important to stress that just 1 per cent of Britain is rewilded today, while around 70 per cent of our land is used for agriculture.
‘And that we could be rewilding 30 per cent of Britain by restoring wild habitats including peatlands, native woodlands, wetlands, rivers and seas – all while maintaining and benefiting productive farmland.’
