THEY’RE a welcome sign that summer is on the way.

And after a decline in numbers due to the bad weather, a survey has revealed that butterflies were fighting back in 2013.

Of the 33 different Oxfordshire species, only five showed a decrease in numbers compared to 2012.

There was a spike in sightings of the common cabbage white butterfly.

The small white, large white and green-veined white had their worst year on record in 2012.

But there was a 10-fold increase in sightings of the large white in Oxfordshire, with numbers up from 315 in 2012 to 3,175 in 2013.

And sightings of the small white soared in 2013, with sightings up from 516 to 5,536.

Dr Marc Botham, butterfly ecologist at the Centre for Ecology and Hydrology in Crowmarsh Gifford near Wallingford, said: “These two species were seen in great numbers throughout the county in August, having been almost absent in spring when their first generation was on the wing, and clearly benefited greatly from the lovely July heatwave.”

Volunteers also recorded a sixty per cent rise in sightings of the small tortoiseshell butterfly.

A total of 777 were spotted in the county in 2013, compared to just 78 in 2012.

In 2013 there was also a huge influx of clouded yellows. Volunteers recorded 50 sightings across Oxfordshire compared to none in the previous year.

But experts warn that numbers for some species still remain low.

Dr Botham said: “In 2012, the butterflies didn’t come out in the rain. It is not just what weather we have, but when we have it.”

Around 1,000 volunteers monitored sites across the county last summer to get the results. The UK Butterfly Monitoring Scheme, which is organised by the centre, found that 2012 was the worst summer for butterflies in the UK since the survey started in 1976. In 2013, 46 out of the 56 species studied across the UK recorded an increase.

Head of monitoring at Butterfly Conservation Dr Tom Brereton said: “The recovery of butterflies in 2013 was highly welcome but there is still a long way to go before butterflies return to former glories.”