Two academics have warned that “‘green’ farming policies may accelerate global biodiversity loss”.

According to the researchers, rewilding, organic farming and the ‘nature friendly farming’ measures included in some government conservation policies risk “worsening the global biodiversity crisis”. They claim they can reduce how much food is produced in a region, driving up food imports and increasing environmental damage overseas.

The article is published in the journal Nature, and was carried out by Professor Ian Bateman from the University of Exeter and Professor Andrew Balmford of the University of Cambridge. Both urge policy-makers to consider a bolder approach known as ‘land sparing’, which they argue is cheaper, more effective, and avoids the displacement of food production and loss of wildlife habitats overseas.

Land sparing involves finding lower-impact ways to boost yields in farmed areas to make space for larger, non-farmed areas of the landscape to be put aside for nature without increasing imports and damaging overseas wildlife.

The researchers claim the approach has been overlooked by policymakers “because of a failure to consider the wider consequences of changes in land management”. They argue the changes that boost wildlife locally “seem superficially attractive, but if food production is reduced there are unavoidable knock-on effects elsewher which must also be taken into account”.

In addition, the researchers cite the influence of the ‘Big Farm’ lobby in maintaining the status quo in agricultural policy, with land-sharing subsidies allocated using a flat rate per hectare (which they say disproportionately benefits the biggest farms) results in the largest 12 percent of farms taking 50 percent of all UK taxpayer subsidies.

They argue that while policy funded measures such as reducing the use of pesticides and fertilisers can sometimes increase populations of more common animals and plants on farms it does little for endangered birds, invertebrates, plants and fungi species that need larger stretches of non-farmed habitat – and by lowering yields can also make matters far worse for overseas biodiversity.

“Rewilding initiatives, wher large areas of land are taken out of farming, can indeed benefit locally endangered species. But unless other areas see compensating increases in food output then this reduces local production, increases demand for food imports, and so damages biodiversity overseas”, added the researchers.

They also argue that organic farming is “even more likely to be damaging” and add “relatively few species will benefit in the farmed area, and the substantially lower yields from this type of farming risk greatly increasing the need for food imports, and hence a country’s impacts on biodiversity elsewher”.

Land sparing, in contrast, involves retaining or creating sizeable blocks of unfarmed land containing larger populations of the many species that depend on natural habitats, as well as boosting farm yields elsewher in the region so that overall production is maintained or even increased.

Ian Bateman, a Professor of Environmental Economics at the University of Exeter Business School, said: “The stakes are too high for policymakers to continue to ignore the promise of land sparing when so much research demonstrates that it is a far more effective approach than many of the strategies being deployed.

“Unless researchers and policymakers assess the overall, global effects of interventions aimed at addressing biodiversity loss and climate change, poor decisions that are unsupported by the data will at best under-deliver, and at worst exacerbate existential threats posed by the extinction and climate crises.”

Andrew Balmford, a Professor of Conservation Science at the University of Cambridge, added: “This issue has become even more urgent since last December when many countries agreed to help meet the Convention on Biological Diversity’s goal of protecting 30 percent of the planet’s land and oceans by 2030.

“Exactly how this 30 percent will be put aside and how we meet humanity’s growing needs on the rest of planet -will in large part determine the biodiversity consequences of this ambitious commitment,” concluded Balmford.