THE numberof butterflies in the UK is beginning to rise again, a study has revealed.
Whilst numbers still remain below average overall, 46 out of 56 species studied in 2013 recorded an annual increase compared to 2012.
Data was collected by the UK Butterfly Monitoring Scheme (UKBMS), jointly led by Lulworth-based Butterfly Conservation and the Centre for Ecology and Hydrology (CEH).
Several rare species revived following 2012 with the Lulworth skipper up by 162 per cent and the critically endangered high brown fritillary up 133 per cent as both responded to conservation work.
Warm weather in the summer saw a huge influx of species migrating from the continent, with the number of clouded yellow butterflies up by 4,373 compared to 2012.
Meanwhile, the small tortoiseshell, a garden favourite, was up by more than 200 per cent in 2012 with last year’s warm summer seeing it record its best year for a decade.
Despite the resurgence, however, overall butterfly numbers were still below average.
A cold spring at the beginning of 2013 saw some of the most threatened habitat specialists suffer.
The endangered pearl-bordered fritillary was down 22 per cent compared to 2012, while the number of grizzled skippers fell by 45 per cent to a series low.
Dr Tom Brereton, head of monitoring at Butterfly Conservation, said there was a long way to go before butterfly numbers returned to normal.
He said: “Our ongoing monitoring efforts will be vital in assessing whether we are on track to reverse butterfly declines and rebuild a healthy countryside.”
UKBMS has run since 1976 and involves thousands of volunteers collecting data every week throughout the summer.
Many UK butterfly species need a warm spring and summer this year to give them the best chance of sustaining a recovery.
Dr Marc Botham, CEH butterfly ecologist, said: “Annual changes are largely associated with the weather.
“However, the data shows that a number of species have been significantly declining over the last 38 years.
“This highlights the importance of maintaining long-term monitoring, reliant on the immense dedication of thousands of volunteers.”