A CRITICALLY endangered butterfly has recorded its best year for a decade following 2014’s warm spring weather, conservationists said.
The high brown fritillary, one of the UK’s most threatened butterflies, once bred in most large woods in England and Wales but has seen numbers tumble in the face of habitat loss in recent years.
But last year, numbers increased by 180 per cent compared to 2013, making it the best year for the butterfly since 2004, the UK Butterfly Monitoring Scheme said.
High brown fritillaries are one of only two critically endangered butterflies in the UK and are restricted to a handful of colonies. The butterfly benefited from the warm, damp spring and from work to restore its habitat, wildlife charity Butterfly Conservation said.
Dr Tom Brereton, head of monitoring at Butterfly Conservation, said: “A huge amount of work has been put into conserving this butterfly in recent years, especially through wildlife-friendly farming schemes, so the results will come as a welcome boost to all involved.”
He said the warm weather would have helped the fritillary caterpillars, which feed on violets, develop more quickly and increase the numbers that pupated successfully.
The warmer than average spring and early summer in 2014 also helped the marbled white, ringlet and brimstone butterflies, which all had their best year since the survey began in 1976.