The Alun Valley Project
The Alun Valley in the Vale of Glamorgan supports what is
thought to be the last population in Wales of the high brown
fritillary. Two other species of fritillary are also found there:
dark green and small pearl-bordered.
In 1999 the population of the high brown fritillary in the Alun
Valley had declined to a dangerous low (see Old Castle Down and
Alun Valley High Brown Transects graph).
In 2003, Butterfly Conservation applied for funding from the
Aggregates Levy Sustainability Fund on behalf of the Vale
Biodiversity Partnership to undertake a habitat management and
restoration programme.
With the help of the Glamorgan Heritage Coast project and a
dedicated team of volunteers, scrub clearance and coppicing has
taken place every winter since 2003 to try to restore breeding
habitat.
Since the work began, the high brown fritillary has undergone
population increases each year and has appeared on all the managed
patches. In May 2006, habitat quality assessment was carried out to
give a “before and after” comparison which showed that:
- The coverage of violets (the larval food plant) had
increased
- Bracken litter, grass/moss and sward height had all
improved
- Both high brown fritillary and dark green fritillary were
breeding on the site as caterpillars were found
Annual transect counts of adult butterflies have shown that the
population has made a dramatic recovery (see the results graph)
The next steps and how to get involved