Two of our butterflies have worst year on record

TWO species of butterfly that were already in decline suffered their worst year on record last year as they struggled in difficult weather conditions.

Conservationists had hoped that butterfly numbers would bounce back after the summer of 2016, the fourth worst year in 42 years of records.

Many spring species emerged earlier than usual following a warm start to 2017.

But a cold snap at the end of April and a gloomy wet summer hit many species that are already struggling, making last year the seventh worst on record, experts said.

Butterflies need warm, dry weather during periods when they are on the wing in order to feed and mate successfully.

Both grayling butterflies and grizzled skippers recorded their lowest numbers since records began, results from the annual UK Butterfly Monitoring Scheme showed. Grizzled skipper numbers were down 9 per cent compared with 2016, and the population of the striking black and white species has more than halved since the 1970s.

Graylings, which have mottled brown wings, declined by 6 per cent on the previous year and its numbers have shrunk by 63 per cent in a decade.

The survey was led by Butterfly Conservation, the Centre for Ecology and Hydrology, British Trust for Ornithology and the Joint Nature Conservation Committee.

As well as rare species, some common butterflies also suffered, with the large white butterfly experiencing falls of 19 per cent year on year, and it is now in a state of long-term decline.

Professor Tim Brereton, of Butterfly Conservation, said that with cold, wet conditions this spring, there are ‘no immediate signs’ things are going to pick up this year.

But some species did better in 2017 than in 2016. Number of red admirals rose by 78 per cent and commas were up 91 per cent.

The rare white admiral bounced back after a ‘terrible’ year in 2016 with an increase of 157 per cent in numbers.