Huge increase in butterfly numbers on Worcestershire reserve

Green veined white. Credit Wildlife Extra.

September 2009. Worcestershire butterflies at Grafton Wood are having a bumper year judging by a recent survey. Volunteers for Worcestershire Wildlife Trust and Butterfly Conservation have spent the last eleven years undertaking weekly surveys in Grafton Wood. Their peak month is always July and until now the average count was around 1100 for the 4 week period. In 2009 the count was 2100 for the same 4 weeks - a remarkable increase.

Painted ladies
John Tilt, organiser of the survey, said "The biggest increases are for painted lady butterflies due to their massive migration to the UK this year. Now these have produced off-spring and we counted 100 in one week. All resident species are showing an increase on the average too."

Silver-washed fritillary
The spectacular, and uncommon, silver-washed fritillary is showing a large increase. Silver-washed fritillaries are so-called because of the silver streaks on the underside of the wings that can be seen as they feed on flowers such as bramble. More common species such as large and green-veined whites, gatekeeper and ringlets also show an increase.

Huge numbers of painted ladies were seen across Britain in 2009. Credit Wildlife Extra.

"The question is why? Our weather is similar to last year, warm and quite wet, so there's no obvious reason. There'll be a lot of analysis to do at the end of the season."

Grafton Wood
Grafton Wood is owned and managed by Worcestershire Wildlife Trust and Butterfly Conservation. Management work in the wood is aimed at helping woodland butterflies to flourish, particularly the nationally rare brown hairstreak, the only colony of which in the Midlands is centred on Grafton Wood.

Management work had involved widening the rides, coppicing and glade creation. Work with local farmers has been vitally important as the surrounding hedgerows are also very important for butterfly populations.

Grafton Wood sits within the ancient boundaries of the Forest of Feckenham and forms part of Worcestershire Wildlife Trust's Living Landscape vision. This identifies a network of areas to protect for wildlife; enlarging, improving and joining them up across the UK.