Image copyright S Petrovan Image caption The brown hare is almost a rarity in some part of the UK

An exotic grass planted on farmland could have unexpected benefits for wildlife, scientists say.

Elephant grass (Miscanthus) planted as a biomass crop is a valuable habitat for the brown hare, according to research.

A study suggests the grass can support hare populations when planted at the right scale.

Numbers of brown hares have declined in the UK over past decades, though they are still common in some areas.

Dr Silviu Petrovan of the conservation science group at the University of Cambridge carried out the research.

"What we strongly suspect is that these areas of Miscanthus are very good at replacing lost diversity in the farmland," he told BBC News.

Image copyright S Petrovan Image caption Brown hare in Miscanthus in May

"If you have a single block of Miscanthus with arable land and grassland fields in the vicinity (mixed farmland) it offers really high quality habitat for brown hares."

In the study, scientists from the University of Cambridge, University of Hull and The Open University radio-tracked brown hares in North Yorkshire across the seasons.

They discovered hares never fed on the grass, but they liked to sleep in it during the day, as they are nocturnal.

Even small areas of elephant grass of only 10 hectares could harbour animals.

But large swathes of Miscanthus were inhospitable, the scientists found.

Miscanthus is grown in many parts of the UK, particularly near power plants, where it is harvested and burned for fuel.

Image copyright S Petrovan Image caption Hare in Miscanthus field after cutting

The grass requires little management and is not sprayed with herbicides.

Dr Phil Wheeler from the Open University, who led the research, said: "In some respects, although these biomass crops are alien to the UK, they mimic unfarmed or unintensively cultivated bits of farmland, many of which have been lost as farming has intensified.

"Our research suggests that for hares, diversifying farmland by planting biomass crops in small chunks might replace something of what has been lost."

But he said if biomass crops are only viable when planted over wide areas, they may end up as another challenge to farmland wildlife.

The research is funded by the wildlife charity, People's Trust for Endangered Species (PTES), and published in the European Journal of Wildlife Research.

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