Heddon Valley is home to a large variety of butterfly species including one of the UK’s rarest butterflies, the High Brown Fritillary. This is one of only four sites in the country where they thrive in good numbers, thanks to careful habitat maintenance by our rangers. Look out for them resting on top of thistles in the riverside meadows or flying in the sunny bracken slopes between June and July.
Butterfly habitat conservation
Over many years now we have been working towards improvements for our butterfly habitats. There are complexes of bracken slopes which, when maintained correctly, provide perfect habitat for the rare high brown fritillary to thrive.
This involves lots of scrub clearance, small amounts of swailing (controlled burning of the heath) and two working groups a year to do surveys and make runnels (paths) through the bracken. Cutting pathways through the bracken allows the butterfly to move through the landscape, and also encourages the growth of dog violets. This flower is where the fritillaries lay their eggs and also forms the main food source for the caterpillars.
As well as the High Brown, the work is beneficial a lot of other butterflies. On his weekly surveys Ranger Dan has recorded up to 11 species on these sites. These include other fritillary species, such as the dark green, small pearl-bordered and silver-washed.
There are also lots of other butterflies in the Heddon Valley, which can usually be seen in the woodlands or meadows on the way to Heddon’s Mouth. Look out for the peacock, red admiral, large white, speckled wood and the elusive green hairstreak.
Key to spotting any of these butterflies is a good set of binoculars and creeping up on them without casting a shadow on a nice sunny day.