2015 will be a good year for butterflies in Britain

This year's warm summer meant the UK saw an increase in butterflies.

Next year could be an exciting one for butterflies if exotic species which appeared in 2014 are able to survive the winter here, conservationists have said.

Species such as the continental swallowtail, the scarce tortoiseshell and the large tortoiseshell were all seen in Britain in 2014 following an unprecedented series of immigration and emergence of exotic butterflies. Words: PA

Wildlife charity Butterfly Conservation raised the possibility that some of these butterflies may be able to successfully overwinter in the UK and emerge again in 2015.

This year saw the offspring of continental swallowtail butterflies, which had arrived in 2013 in the largest numbers since 1945, emerging in late spring as adults along the south coast from Suffolk to Dorset.

If the species manages to overwinter and emerge again next spring it would suggest it is attempting to colonise southern England, Butterfly Conservation said.

In an even more surprising development, the scarce tortoiseshell - which as its name suggests is extremely rare - appeared in the UK for the first time since 1953.

More than 20 sightings of the butterfly, also know as the yellow-legged tortoiseshell, were reported in several counties, mainly along the east coast around Norfolk but also as far as Devon, Tyneside and the West Midlands, the charity said.

The species is found from Eastern Europe to China and Japan, and has recently spread westwards towards Sweden.

Unless the UK experiences a colder than average winter the prospects are not good for the butterfly, which prefers colder conditions.

But if it is able to hibernate and emerge in 2015, it would be the first time it has done so in 300 years of butterfly monitoring, Butterfly Conservation said.

The large tortoiseshell, meanwhile, was lost as a breeding species in the UK more than 40 years ago, but this year was regularly seen in southern England during the summer.

It has increased in the Channel Islands in recent years, raising the possibility it could return to the UK.

There was also a spate of sightings of the clouded yellow butterfly from early to mid-November, and the experts said a mild winter could see it surviving into 2015.

Dr Tom Brereton, Butterfly Conservation head of monitoring, said: "The emergence and immigration of continental swallowtails and scarce tortoiseshells has made 2014 a truly remarkable butterfly year and with a bit of luck, 2015 could shape up to be even more memorable.

"There have been lots of exciting stories recently of birds, dragonflies, moths and other insects colonising the UK as the climate has warmed up.

"This year's events show that butterflies are finally getting in on the action, giving a much needed boost to our depleted butterfly fauna."

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