“Land sparing” could lead to dramatic increases in wild bird populations, according to research that bolsters the case for rewilding.

Farming intensively to increase yields while turning over much larger areas of farmland to wildlife could – if combined with measures to cut food waste and meat consumption – meet Britain’s food needs and more than double the populations of breeding birds.

It has been calculated that farmed land in Britain must increase by 28% if it is to supply the growing demand for food by 2050. Andrew Balmford, a professor of conservation science at the University of Cambridge, said this conundrum could not be solved by just reducing demand for food – yields must be raised too.

Increasing yields is controversial among some conservationists who argue that intensive farming is unsustainable. Upland farmers also object because they fear land sparing will force them to give up farming and rewild their hillsides, while the fertile lowlands are intensively farmed.

In research presented to a rewilding conference organised by the Cambridge Conservation Forum, Balmford and a team of researchers studied food production and birdlife on the Cambridgeshire Fens to model how a far greater area of farmland could be devoted to wildlife.

By dramatically increasing spared land from 5% to 50%, bird populations soared on average by approximately 250%, with species such as bitterns and bearded tits prospering on rewilded fenland. The quarter of land cultivated by traditional, low-intensity farming was important for conservation too: this helped bolster farmland species such as the grey partridge and yellowhammer.

Yellowhammer singing

While organic farmers and most conservationists fear raising yields would lead to more environmental damage such as greenhouse gas emissions and increased nitrate pollution, recent research by Balmford and colleagues found that in four types of farming, including European dairy farming and wheat production, intensive systems were often less polluting per unit of production than organic and low-intensity agriculture.

But Balmford said there was not enough data on other “externalities” such as soil erosion to measure the full, long-term costs of high-yield farming. On the Fens, for instance, there is scant data on soil erosion. The Fens’ fertile, peaty soil being washed away or eroded by the wind could prevent high-yield farming in the future.

Read the full article here

Related content