Rewilding, organic farming and the so-called ‘nature friendly farming’ measures included in some government conservation policies may accelerate global biodiversity loss, say two leading researchers.
These ‘Green’ farming policies risk worsening the global biodiversity crisis by reducing how much food is
produced in a region, driving up food imports and increasing environmental damage overseas.
In an article published today in the journal Nature, Professor Andrew Balmford at the University of
Cambridge, and Professor Ian Bateman at the University of Exeter, urge policy-makers to consider a
bolder approach known as ‘land sparing’ – which they argue is cheaper, more effective, and avoids
displacing food production and worsening the loss of wildlife habitats overseas.
Land sparing involves finding lower-impact ways to boost yields in farmed areas, and allow larger, non-
farmed areas of the landscape to be put aside for nature – without increasing imports and damaging
overseas wildlife.
The researchers say the approach has been overlooked by policymakers because of a failure to consider
the wider consequences of changes in land management. They argue that changes that boost wildlife
locally seem superficially attractive, but if food production is reduced there are unavoidable knock-on
effects elsewhere that must also be taken into account.
They also 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 disproportionately benefits the
biggest farms – resulting in the largest 12 per cent of farms taking 50 per cent of all UK taxpayer
subsidies.
Their article debunks some of the benefits to biodiversity of three widely-advocated green farming
approaches.
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, where 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.
They also argue that organic farming, where crops are produced without manufactured fertilisers and
modern pesticides, is even more likely to be damaging. 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 elsewhere.
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
elsewhere in the region so that overall production is maintained or even increased.
Promising methods to boost crop and livestock yields more sustainably than current high-yield practices
include genomic screening and gene editing to accelerate animal and crop breeding; using new advances
in aquaculture to produce high value foods with much lower environmental impacts; and, in tropical
countries, greater access to improved pasture and veterinary care.
The researchers point to field studies on five continents that consistently show how land sparing delivers
far greater biodiversity gains than conventional ‘nature friendly farming’ policies.
They say it is likely to cost a great deal less as well: a survey of UK farmers last year found that land
sparing could deliver the same biodiversity outcomes for birds as conventional approaches but at 48 per
cent of the cost to taxpayers, and with a 21 per cent lower impact on food production.
Professor Bateman, a Professor of Environmental Economics at the University of Exeter Business School
who has advised seven UK secretaries of state for the environment in the past decade, 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 who has led 20
years’ work investigating how to reconcile food production with biodiversity conservation, 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 per cent of the planet’s land and oceans by
2030.
“Exactly how this 30 per cent 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.”