Earlier this year, Business Echo reported on the plight of the dingy skipper butterfly. John Dean reports on a project that is transforming an opencast site to the butterfly's benefit

A DELICATE operation to transport rare butterflies to a new home on a North-East opencast site has been hailed a success.

The work to preserve dingy skipper butterflies was carried out on UK Coal's Southfield, site at Royal Oak, near Shildon, in County Durham.

Managers worked on the project with ecologist Gary Tudor, of Applied Ecological Services Limited, which is based in Ramshaw, Teesdale.

UK Coal started mining at the site four years ago and the end of last month marked the end of the extraction and the beginning of a ten-year restoration programme.

Surveys identified the presence of dingy skipper on a small corner of the hectare site, and a decision was taken to protect it from mining.

The dingy skipper - a rarity in the North-East - likes brownfield sites because they support its food plant, the birds-foot trefoil.

However, the butterfly is coming under increasing pressure as such areas are redeveloped and tidied up as part of building projects by developers who do not want patches of scruffy-looking grassland on their sites.

To increase numbers at Southfields, the decision was taken to remove some of the butterfly's eggs, complete with soil and vegetation, from the colony and place them a short distance away on a newly-created scrubland site.

The work started last year, and this year the butterflies have started to colonise the new site as well as continuing to thrive on the old one.

Mr Tudor said: "Our preliminary surveys had shown that there were about 50 dingy skippers on the old site and we decided to leave that as it was. It was not touched, because improving such areas destroys the habitat for the butterfly. About 50 insects remain there.

"We have now created an additional two-hectare site in an area, which was an eyesore, and after the eggs hatched out successfully, numbers are growing there and it is being colonised by wild plants.'

To carry out the work, overseen by UK Coal foreman John Dempsey, now retired, the team had to redesign some of its digging machinery.

Because scooping up the earth using a traditional earth cutter would have damaged the flaky soil, they designed a flat device that effectively sliced it off a few centimetres below the surface, allowing plant roots and eggs to be moved undamaged.

Graham Hindmarsh, UK Coal site manager, said: "In the old days, areas like this would just have been lost. We had to modify our equipment, and it was trial and error, but we believe it was the first time that a translocation like this had been carried out in this way in County Durham."

The work is only part of the restoration scheme at the site, which has included creating ponds, planting species-rich grasslands and large areas of woodland, as well as reinstating hedgerows, much of it on areas that were agricultural before opencast mining began, and not particularly wildlife-friendly.

The result has been increasing numbers of birds, such as skylark, grey partridge and lapwing, as well as a variety of butterflies and other insects.

One of the aims has been to create wetland areas which will encourage the return of water vole, which have been reported in the area.

In July, the company won a County Durham Environment Award, presented by Durham County Council. UK Coal won the waste category prize for its restoration of the Old Eldon tip, in south Durham.

UK Coal has previously been honoured for work at Rainton Meadows, another former mining site, near Houghton-le-Spring, Wearside, which is now home to Durham Wildlife Trust's Rainton Meadows nature reserve.

Company national land rehabilitation manager Trevor Hind, speaking on a visit to Southfields, said: "These awards are a recognition of the restoration work that we do. We are proud of the work that we do at places like Southfields."

Durham County Council minerals department monitoring officer Mike Tweddle, who worked with the company on the project, said: "It is a payback for getting the planning permission and it is an excellent example of what a company can achieve when it comes to enhancing wildlife areas."