Britain's rarest butterflies face extinction as string of rainy summers cause problems

SOME of Britain's rarest butterflies are at an increasing risk of extinction as they struggle to recover from a series of rainy summers.

Monitoring of butterflies at more than 1,000 sites has raised particular concerns about the Duke of Burgundy, which last year had its worst year for more than 30 years.

The butterfly, which used to be a common sight in woodland clearings, has seen its numbers hit new lows each year for the past three summers.

Last year was also the worst yet for the Lulworth skipper. Its numbers have declined by 78 per cent in 18 years, the UK Butterfly Monitoring Scheme by Butterfly Conservation and the Centre for Ecology and Hydrology showed.

Other species, such as the pearl-bordered fritillary and the high brown fritillary, have also suffered severe declines over the past three decades.

Conservationists believe the two extremely wet summers in 2007 and 2008, followed by above-average rainfall in July and August 2009, have accelerated long-term declines suffered by the butterflies, which find it hard to survive heavy rain.

Wider monitoring by Butterfly Conservation of the sites where the rare butterflies are found shows there are fewer than 80 colonies of the Duke of Burgundy across the UK, while the high brown fritillary has fewer than 50 colonies.

The wood white and Lulworth skipper are both down to fewer than 100 colonies, the conservation charity said.

More common butterflies have also had a hard time, with data collected by the UK Butterfly Monitoring Scheme revealing that species, such as the wall brown, small skipper and green hairstreak, had all suffered low numbers last year.