According to the charity Butterfly Conservation, the record-breaking temperatures this summer have been a blessing for Britain's hard-pressed butterflies, and have resulted in some astonishing findings.

Many species have thrived in the hot weather, including some rarities such as:

* Adonis Blue - more seen at a Dorset site on one day this August than in whole summers since monitoring began there in 1980! This species declined by 52% nationally in the last century, but good numbers have been found on other sites too this year.

* Wood White - best year in a decade at a Surrey stronghold (this species declined by 76% in the last century).

* The High Brown Fritillary and Silver-studded Blue, both top conservation priorities in the UK Biodiversity Action Plan, have also prospered.

Scarce species have also colonised new sites or undergone remarkable movements:

* Silver-spotted Skipper - this rare butterfly has re-colonised nature reserves in central Hampshire where it became extinct in the 1970s.

* Dark Green Fritillary - seen in Wharfedale for the first time in 50 years.

* Chalkhill Blues - have been recorded 20 miles or more away from their colonies in both Essex and Suffolk.

Some species have continued to spread northwards in response to the warmer climate:

* Comma - recorded in Fife for the first time in almost 200 years.

* Speckled Wood - found in the Outer Hebrides for the first time ever.

* Migrant butterflies have also had a spectacular year. In particular, large numbers of Painted Ladies arrived in June from North Africa, spreading as far north as Shetland, and are having a very successful breeding season in the UK. Long-tailed Blues and Swallowtails have also been seen in numbers on the south coast.

Common 'garden' butterflies have enjoyed the long, hot summer too. Notably, the Small Tortoiseshell is having a great year after several years of worryingly low numbers.

Richard Fox, Surveys Manager with Butterfly Conservation, said:

"This has been an excellent year for almost all our butterflies. So many people work hard every year to conserve our declining butterflies, whether in their gardens, on farmland or in nature reserves, and this is the pay back on all that investment. Butterfly numbers are governed by the weather, but without the protection and management of the habitats they need, many species would be lost altogether. When hard work by conservationists, landowners and the public coincides with great weather, our hard-pressed butterflies are able to win back some of the lost ground."

Butterfly Conservation works to save butterflies, moths and their habitats. Why not become a member by visiting their web site at: http://www.butterfly-conservation.org/

All you ever needed to know about Britain's Butterflies is contained in our highly popular guide, packed full of stunning photographs, and sales from the book support the work of Butterfly Conservation. To purchase a copy click on the front cover.