WALKERS and trippers to the Yorkshire Dales are being asked to keep a watchful eye open for Britain's only green butterfly, the green hairstreak.
Like many other species of butterfly, its numbers are believed to be in decline and scientists need information about its distribution across the park so that efforts cane be taken, if necessary, to protect it.
Dales visitors on the look out for the Green Hairstreak
Photo: Dave O'Brien
To draw up such a plan, they need accurate, up-to-date information so the Yorkshire Dales National Park Authority has linked with Butterfly Conservation to launch a park-wide survey and they are particularly keen to receive reports of sightings from walkers who visit the more remote areas.
Ian Court, the YDNPA's species officer, says: "We know relatively little about the distribution of the green hairstreak in the park, which makes it difficult to keep track of numbers and to ensure they are surviving here.
"It is unmistakeable, the only butterfly in this country with green wings and when it is perched it closes them, showing the green underside and white streaks.
"We are asking people who see them while they are out and about to make a note of the date, the place, including a grid reference, and the number seen."
Green Hairstreak caterpillars feed on bilberry and so the adults are most often seen between late April and mid to late May in areas where bilberry is abundant. The most likely sites to look for this species are on sheltered slopes on moorland or moorland edge where bilberry is abundant.
The Green Hairstreak survey is the first in a number that the YDNPA and Butterfly Conservation will be asking visitors to take part in this year.
Butterfly Conservation spokesman Sam Ellis said: "We hope people will help us to gather more information about this species. The more we know about it, the more we can do to protect it and to make sure it thrives in the Yorkshire Dales."
- The YDNPA has produced a leaflet and a form that should be completed and posted back free of charge. Called 'Have you seen a Green Hairstreak butterfly this year?', it can be obtained from national park information centres and tourist information centres at Horton-in-Ribblesdale, Leyburn, Richmond, Settle and Skipton.