Farm animals keep vole army at bay

Giving a mix of farm animals a controlled ’right to roam’ will help to improve biodiversity and solve a vole conservation dilemma in upland Britain, according to new research published today in the Journal of Applied Ecology.

As numbers of hill farmers and grazing animals dwindle, field voles are thriving in undisturbed upland and forest areas. This is great news for protected birds of prey such as hen harriers that use voles as a source of food, but not so good for Britain’s upland forests as the growing army of voles enjoy banqueting on young tree saplings.

The new research, carried out by a team of scientists from Scotland, suggests mixed farming of sheep and cattle, once common in the British landscape, should be reintroduced. This step, combined with some simple changes to forest management – such as allowing farm animals managed roaming rights within the landscape – will allow vole numbers to be controlled, helping to conserve and improve the mix of plants, trees and other wildlife.

Lead author, Dr Darren Evans from the Centre for Ecology & Hydrology, said “This is the first time that a scientific link has been shown between livestock grazing methods and vole numbers. Our work has revealed that a return to mixed farming with managed ’right to roam’, provides a positive way of managing our upland areas to benefit conservationists, foresters and farmers.”

Dr Evans explained “Voles are often seen as public enemy number one for young forests but, by forming a new partnership between forest managers and upland farmers, we can get the best mix of biodiversity and commercial tree planting, while conserving an important food source for the birds of prey.”

Mixed farming where animals such as sheep, cows, horses and goats lived together on a single farm was a common sight in Britain until the 1950s, before agricultural reform changed the way much of the uplands were managed.

A new PhD student at the Macaulay Institute is taking the vole research further, and trying to answer some of the questions it has raised. The student is co-supervised by staff at the Centre for Ecology & Hydrology and the University of Aberdeen.