Restoring wildlife habitats in wealthy nations could drive extinctions in species-rich regions, experts warn

Some efforts to preserve or rewild natural habitats are shifting harmful land use to other parts of the world – and this could drive an even steeper decline in the planet’s species, according to a team of conservation scientists and economists led by the University of Cambridge.    

Researchers from over a dozen institutions worldwide have come together to call on the global community to acknowledge the “biodiversity leak”: the displacement of nature-damaging human activities caused by ringfencing certain areas for protection or restoration.

They argue that rewilding productive farmland or forestry in industrialised nations that have low levels of biodiversity may do more harm than good on a planetary scale.

Exploratory analysis by the team suggests that reclaiming typical UK cropland for nature may be five times more damaging for global biodiversity than the benefit it provides local species, due to the displacement of production to more biodiverse regions.   

While this “leakage” has been known about for decades, it is largely neglected in biodiversity conservation, say the researchers. They argue it undermines actions ranging from establishing new nature reserves to the EU’s environmental policies.

Writing in the journal Science, the experts point out that even the UN’s landmark Global Biodiversity Framework – aiming for 30% of the world’s land and seas to be conserved – makes no mention of the leakage problem.

“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 Prof Andrew Balmford from the University of 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 first thing we need to do is collectively acknowledge that these leaks exist,” said co-author Prof Brendan Fisher from the University of Vermont. “If protesting a logging concession in the US increases demand for pulp from the tropics, then we are unlikely to be helping biodiversity.”

Co-author Dr Ben Balmford of the University of Exeter said: “This issue demands far greater attention from a sector that seeks to shape how 30% of an ever hungrier and more connected planet is managed.”

‘Leakage’ is already a major issue for carbon credits tied to forest preservation, say researchers. But they argue it’s a real problem for biodiversity conservation efforts too.

While protected areas can slow deforestation inside their borders, there’s evidence it can simply shift to neighbouring areas. Production can also be displaced much further. Efforts to protect the Pacific Northwest’s old-growth forests resulted in increased logging in other North American regions, for example.

Yet a survey of site managers of tropical conservation projects conducted by the Cambridge team found that 37% had not come across the concept of leakage, and less than half of the projects were attempting to curb any displacement damage.*

The researchers explored how leakage caused by protected areas could affect global biodiversity by applying real-world food and biodiversity data to two hypothetical conservation projects.

They found that rewilding a sizeable area of Brazilian soybean farms would push production to nations such as Argentina and USA, but because Brazil is so important for biodiversity, the local conservation gains could be around five times greater than the displacement harms.

The opposite would be true if the equivalent area of UK arable farmland was reclaimed for nature. Here, production 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 biodiversity. 

The experts offer a number of ways to help plug the biodiversity leak. They call on governments and the conservation sector to take leakage far more seriously when making environmental policy at national and global level.

They also point out that leakage could be reduced if conservation projects work with others to reduce demand – especially for high-footprint commodities such as red meat.

There’s scope to limit leakage by targeting conservation to areas high in biodiversity but where current or potential production of food or timber is limited, say researchers. One example is restoring abandoned tropical shrimp farms to mangroves.

However, we should also be much more cautious about restoring natural habitats on currently productive farmland in less biodiverse parts of the world, they argue.

Beyond planning where to conserve, major conservation initiatives should work with partners in other sectors to support local farmers, so that overall levels of production are maintained in the region despite protected areas. The team cite examples ranging from forest-friendly chocolate to herding practices that protect snow leopards.

Where local yield increases are difficult, larger-scale programmes could establish long-range partnerships with suppliers in the same markets to make up shortfalls in production.

“Without attention and action, there is a real risk that the biodiversity leak will undermine hard-won conservation victories,” said co-author Dr Fiona Sanderson from the Royal Society for Protection of Birds, who works on reducing the impacts of cocoa production in Sierra Leone.

Lead author from Cambridge, Prof Andrew Balmford, added: “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.”  

Notes: 

*Survey of 100 practitioners involved in area-based tropical conservation projects, including directors, managers, coordinators, and researchers. Respondents came from 36 countries across all five continents. Further details: https://zenodo.org/records/14780198

** Two hypothetical habitat restoration programs covering 1000km2 of Brazilian soy-producing land, and restoring 1000km2 of arable farmland in the UK that produces wheat, barley and oilseed rape.

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