Butterfly numbers plummet in disastrous washout summer

Of 56 species monitored, 52 saw falls from the previous year, with 13 experiencing their worst year in records dating back to 1976 as they struggled to find food and shelter and mate in the washout summer.

Threatened species were already experiencing long-term declines before the deluges of 2012 and wildlife experts are now warning struggling butterflies could become extinct in some areas of the UK as a result of the wet weather.

The critically endangered high brown fritillary saw numbers fall by 46 per cent on the previous year and the endangered heath fritillary saw numbers halve, the UK Butterfly Monitoring Scheme by Butterfly Conservation and the Centre for Ecology and Hydrology found.

The black hairstreak, one of the UK’s rarest species, saw its numbers fall by 98 per cent, while the green hairstreak was down by 68 per cent and the white-letter hairstreak down 71 per cent.

Common species also suffered, with the common blue numbers falling by 60 per cent, brown argus down by 73 per cent and large skippers down by 55 per cent.

The two cabbage white species both saw their numbers collapse by more than half, while the small tortoiseshell saw its populations falls of 37 per cent.

Only four species saw populations increase in 2012.

Tom Brereton, head of monitoring at Butterfly Conservation, said: “2012 was a catastrophic year for almost all of our butterflies, halting progress made through our conservation efforts in recent years.”