High Brown Fritillary made a bumper early appearance

High Brown Fritillary in the sun on a plant

The UK’s most endangered butterfly, the High Brown Fritillary, made a bumper early appearance at a remote British habitat in North Devon, despite serious worries about their population.

The High Brown Fritillary has been recorded as being spotted slightly earlier than usual in 2018 and these early counts reveal excellent numbers. 

Known as the UK’s most endangered butterfly,  this recent discovery is despite previous grim population numbers. The survey was undertaken in Heddon Valley in North Devon, and this rise in figures is because of - 

  • Excellent habitat management, the team at Heddon Valley in North Devon have introduced broad swathes created by using roboflail, and looking after the surrounding area to make it perfect for butterfly survival. 
  • Ideal weather conditions, a cold harsh winter has helped knock back braken on the coast path. Followed by good warm weather in May and June is ideal for catepillar development. 

UK butterfly expert, Matthew Oates has been in the Heddon Valley in North Devon taking part in an annual count of this rare butterfly along with the help of other volunteers.  He said: “The butterfly seems to be having a very good year with over 200 seen during the count.  As we are having some fairly dry weather, it’s now the perfect time for seeing this large and powerful butterfly”. 

High Brown Fritillary
High Brown Fritillary on a green leaf in the sun
High Brown Fritillary

Why was the High Brown Fritillary endangered? 

Over the last 50 years, the UK population of High Brown Fritillaries has declined rapidly, due a number of reasons- 

  • Woodland management and, more recently, the abandonment of marginal hill land. Butterflies need large areas of the countryside to survive in good numbers
  • Habitats being overwhelmed by pressures from agriculture and development
  • Climate change and nitrogen deposition from the atmosphere are almost certainly contributing to the High Brown’s demise.

Overall, the UK population has declined by 66% since the 1970s.


What's next?

The Trust is embarking on ambitious plans to develop 60 hectares of lowland heath and wood pasture – the butterfly’s principle habitat – to give it a fighting chance for the future. The project has been made possible thanks to a generous award of £100k made to the National Trust by Postcode Earth Trust, raised by players of People’s Postcode Lottery. This is part of an award of £750,000 this year towards several conservation projects and Heritage Open Days. 

This project  will focus on restoring parts of the natural landscape along the Exmoor and North Devon coast to make it more suitable for the butterfly and other wildlife including the Heath Fritillary, Nightjar and Dartford warbler will also benefit. 

Thanks to your support the National Trust is working with its tenants and partners including Butterfly Conservation to reverse the alarming decline in UK wildlife, aiming to restore 25,000 hectares of wildlife-rich habitat by 2025.