Hilly areas are better for butterflies

Research using satellite images has shown rugged, hilly areas with a mix of habitats such as woodland and grassland can help maintain more stable butterfly populations, scientists said today.

The study found species such as the brown argus and dingy skipper had more stable populations in varied terrain - helping them survive better in the face of threats such as drought.

The findings, based on data from satellites which showed the topography of the land and the kinds of habitats in them, could be used to design landscapes to help conserve insect species.

The study of 35 British butterfly species from 166 sites across the UK looked at populations over an 11-year period and compared the data with the diversity of habitat and landscape in the surrounding area.

The research by the Centre for Ecology and Hydrology (CEH), Butterfly Conservation and the University of York found that places with a greater range of habitats had more stable butterfly populations.

Areas with varied features, such as slopes facing north, south, east and west, were also better for the insects, the study published in the journal Ecology Letters found.

For some butterfly species, the diversity of habitats up to 5km (3 miles) away had an impact on their populations.

Dr Jane Hill, of the department of biology at the University of York, said: "Our findings show that more diverse landscapes may provide a greater range of resources and microclimates, which can buffer insect populations from declines in difficult years."

The study's lead author, Dr Tom Oliver from CEH, said: "More stable insect populations are better for conservation because it means that, in years with extreme weather - e.g. drought years - populations are less likely to go extinct."

Dr Tom Brereton, head of monitoring at wildlife charity Butterfly Conservation, said the results highlighted the importance of taking a "landscape perspective" for species conservation.

Dr David Roy, from CEH, said: "With a rapidly changing climate, we need our landscapes to support biodiversity as well as provide other ecosystem services such as food production and clean water.

"Using remotely-sensed land cover data from satellites to design landscapes may help us to achieve the right balance."

The scientists used UK Land Cover Map data which shows the structure of the landscape and vegetation across the country.