THE population of a common butterfly has soared in the past year, with numbers increasing substantially in some parts of Scotland.

Conservationists said it had been a good year for the red admiral, with numbers in the east of Scotland alone going up from the two recorded in 2013 to 79 in 2014.

In Glasgow and South West Scotland, only one was recorded in 2013 but by last year, 10 were spotted in Ardochrig Hill. In the Highlands, seven were seen in Castlehill, compared with none the year before.

Butterfly Conservation, which compiled the numbers through its monitoring scheme, said it was also an excellent year for two priority species - the pearl-bordered fritillary and the chequered skipper.

The large and small skipper both did well, expanding their ranges northwards due to the warmer weather experienced last year.

It came as UK-wide figures showed one of the most threatened butterflies had recorded its best year for a decade following 2014's warm spring weather.

The critically endangered high brown fritillary saw numbers increase last year by 180 per cent compared to 2013, making it the best year for the butterfly since 2004, figures from the UK Butterfly Monitoring Scheme showed.

The butterfly, which once bred in most large woods in England and Wales but has seen numbers tumble in the face of habitat loss, benefited from the warm, damp spring and from work to restore its habitat, wildlife charity Butterfly Conservation said.

High brown fritillaries are one of only two critically endangered butterflies in the UK and are restricted to a handful of colonies in north west and south west England and one in Wales.

Dr Tom Brereton, head of monitoring at Butterfly Conservation, said: "The high brown fritillary is one of only two butterflies classed as critically endangered in the UK so it is fantastic news that numbers are at their highest level for more than a decade.

"A huge amount of work coordinated by Butterfly Conservation has been put into conserving this butterfly in recent years, especially through wildlife-friendly farming schemes, so the results will come as a welcome boost to all involved."

He said the warm weather would have helped the fritillary caterpillars, which feed on violets, develop more quickly and increase the numbers that pupated successfully.

The areas where the butterfly had done well were all in wildlife-life friendly farming schemes where the habitat was being managed specifically to help the species, he said.

The warmer than average spring and early summer in 2014 also helped other species of butterfly which emerge early in the year, including the marbled white, ringlet and brimstone butterflies which all had their best year since the survey began in 1976.