Impact of Management for Pearl-bordered Fritillary in the Wyre Forest

Following close partnership working in the Wyre Forest through a series of projects, the total area occupied by Pearl-bordered Fritillary in the landscape has now increased.

Pearl-bordered Fritillary is one of the fastest declining butterflies in the UK, having suffered a 66% decline in abundance between 1977 and 2004. The Wyre Forest is one of the English strongholds for the butterfly.

Pearl-bordered Fritillary requires abundant violets, usually Common Dog-violet viola riviniana, growing in short, sparse vegetation with abundant leaf litter or dead Bracken. Pearl-bordered Fritillary in the Wyre Forest mainly occurs in woodland clearings created by coppicing or clear-fells but can also occur in other areas of open space such as; deer lawns and disused railway lines with a grassland/Bracken mosaic. 

The Wyre Forest consists of 2,634 ha of ancient woodland and is one of the most ecologically diverse in England.  In 1997 Pearl-bordered Fritillary was recorded on 41 Wyre Forest sites, by 2002 it was recorded on 32 sites and declines in abundance since 1997 meant 76% of the sites only supported small colonies.

Project Aim

Between 2003 and 2012, through a series of funded projects, Butterfly Conservation worked closely with partner organisations co-ordinating surveys and monitoring as well as providing management advice.  The project aimed to conserve Pearl-bordered Fritillary by maintaining and expanding existing breeding habitat throughout the forest and by identifying new sites.

Methods

• 41% of occupied sites were managed through clear-fells and coppicing and 22% by ride and track work.

• 29% are areas of permanent open space managed by; Bracken rolling, annual cut and collect programmes, grazing and site enlargement.

• 21 sites were managed by opening up south-facing slopes, improving linkages, liming trials, scalloping and stump removal.

• Since 2002 a Pearl-bordered Fritillary monitoring programme has been set up and includes monitoring by transects and timed counts, monitoring data can help to target management.

Results

• Pearl-bordered Fritillary has occupied or continued to occupy at least 68 sites in the Wyre Forest from 2002-11.

• Total number of occupied sites monitored by timed counts increased from 15 in 2002 to 30 in 2011.

• The number of large colonies on sites monitored by timed counts increased from no large colonies from 2002-09, to 11 large colonies in 2011.

• The total area occupied by Pearl-bordered Fritillary increased from 27.07 ha in 2002 to 52.11 ha in 2011.

• Over half of the new colonisations were in habitat adjacent to or within 0.25 km of an existing population.

• The butterfly benefited from a variety of management and is successfully managed in the long-term by maintaining open space.

• Management was found to benefit other Lepidoptera species including; Wood White, Grizzled Skipper, Silver-washed Fritillary and Drab Looper.

• Volunteer efforts were vital and through the project there have been a number of work parties and the Wyre Forest Butterfly Recorder’s Group has been established following butterfly ID courses.

Success!

This project demonstrates that Pearl-bordered Fritillary can benefit from a variety of targeted management with open space and ride/track management being just as important as coppicing and clear-fell.  Close partnership working (especially with Natural England and the Forestry Commission) has also been important in the successful conservation of Pearl-bordered Fritillary in the Wyre Forest and future management will focus on improving connectivity and providing more long-term sustainable coppice.

Funders

The Heritage Lottery Fund, SITA Trust, The Tubney Charitable Trust, Countdown 2010, Forestry Commission England and Butterfly Conservation Members and Donors.