After suffering through their worst year on record in 2012, new figures show butterflies made a come-back in 2013, but numbers of the pollinating insects were still lower than average.

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Record breaking rainfall and one of the coolest, dimmest summers since records began hit butterflies hard, though the UK Butterfly Monitoring Scheme (UKBMS) showed that much more clement weather last year led to a recovery in numbers. Preliminary results of another study, the Wider Countryside Butterfly Survey, published in February, showed that although winter and spring were unsettled in 2013, a hot, bright summer led to an increase in butterfly numbers.

However, the cold spring took a toll on certain 'specialist' species reliant on specific habitats, many of which are already suffering the effects of habitat loss.

On Wednesday, the Centre for Ecology and Hydrology and Butterfly Conservation which carry out the BMS survey revealed that 46 out of the 56 butterfly species studied had recorded an annual increase compared to 2012.

Common species such as the Small, Large and Green-veined White, all of which had their worst year on record in 2012, bounced back to above average numbers in 2013 with all three increasing by more than 100 percent. Small tortoiseshells – a common sight in gardens – also recovered, with numbers up by more than 200 percent.

CEH added that the weather also boosted numbers of rare and threatened butterfly species, which responded especially well to conservation work, and even attracted an influx of migrant butterflies – including Clouded Yellow butterflies, which increased by 4,000 percent – from Continental Europe.

However, the two groups said that numbers were still worryingly low, especially given long-term trends for butterfly decline; many species, especially specialists and grassland butterflies have declined dramatically in Europe over the past three decades.

CEH butterfly ecologist Dr Marc Botham Commented, "Annual changes are largely associated with the weather. However, the data show that a number of species have been significantly declining over the last 38 years. This highlights the importance of maintaining long-term monitoring… to determine species and habitats of conservation priority."

CEH said extreme rainfall in 2012 dealt a heavy blow to many butterflies, with populations of rare species such as Duke of Burgundy becoming locally extinct. Many UK species now need a warm spring and summer this year to give them the best chance of sustaining a recovery.