Five rare butterflies could go extinct in Britain following a run of wet summers, according to conservationists.
By Louise Gray, Environment Correspondent
Published: 7:30AM GMT 05 Mar 2010
The annual survey of butterfly numbers in the UK found that the wet weather for the last three summers has made it difficult for the insects to breed.
If there is another washout summer then certain species, that were once widespread, coud be lost forever.
The Duke of Burgundy, High Brown Fritillary, Wood White, Lulworth Skipper and the Pearl-bordered Fritillary have already suffered from loss of habitat and pollution.
But the wet weather makes it impossible for the delicate creatures to fly out to collect nectar and ultimately to breed.
The Butterfly Conservation survey of 1,000 sites across the UK found that overall butterfly numbers are still much lower than average since monitering began in 1976.
The Duke of Burgundy, that used to be a common sight in woodland clearings, is at its lowest level since monitoring began with less than 80 colonies in the UK. The High Brown Fritillary is even lower in numbers with just 50 colonies left in the UK. The Wood White, Pearl-bordered Fritillary and the Lulworth Skipper are all down to under 100 colonies.
Dr Tom Brereton, head of monitoring at Butterfly Conservation, said butterflies need shelter in the rain meaning they cannot fly out to find food and to breed.
"Some of the species are at particularly low levels and another bad year could tip them over the edge," he said.
"Heavy rain effects all butterfly activity, it means less eggs are laid and fewer adults survive.
"We've had bad years in the past such as 1982 but butterflies were in a better state then, the rarer they get the harder it is for them to bounce back."
In 2009 the UK saw millions of the summer migrant Painted Lady butterflies because of a good breeding year in Africa. But relatively common species including the Wall Brown, Small Skipper and Green Hairstreak remained very low numbers in 2009. The Small Tortoiseshell, which has suffered a serious decline in recent years, made a slight comeback.
Dr Brereton blamed the decline on climate change the loss of crucial habitats such as flower rich grassland and the intensification of farming methods – as well as the weather.
"We will just have to keep our fingers crossed we have a sunny summer," he added.