The Blackdowns Butterfly Project
BC Somerset and Bristol branch, in collaboration with the BC Devon branch are funding ‘The Blackdowns Butterfly Project’ which is looking at four species of butterfly.
We are keen to try to prevent any further decline or loss to the Duke of Burgundy and the Small Pearl-bordered Fritillary and to see if it is possible to re-establish the Marsh Fritillary and the Wood White in the Blackdown Hills.
Somerset & Bristol Butterfly Conservation branch committee are particularly concerned about the decline of four species of butterfly from our region.
The Marsh Fritillary and Wood White have already gone, the Duke of Burgundy is on the verge of disappearing and the Small Pearl-bordered Fritillary has already been lost from some sites, including our own Mount Fancy Farm BC Reserve.
As a branch, we are keen to try to prevent any further decline, or loss of these species and to see if it is possible to re-establish the Marsh Fritillary and the Wood White in the Blackdown Hills. John Andrews, the Chair of Somerset & Bristol branch put a proposal forward to Butterfly Conservation head office and we are pleased to say that it was approved.
Somerset and Bristol BC branch, in collaboration with the Devon BC branch will be funding this project, which will initially be referred to as ‘The Blackdowns Butterfly Project’.
The focus in the first year will be on the Marsh Fritillary and the Small Pearl-bordered Fritillary when we are employing a specialist to carry out an inventory of sites previously populated by these two species and also look at the habitat of potential sites. It will be followed by surveying and recording of butterflies during the flight season. This part of the project will need help from volunteers.
We hope that the results from the initial research & surveys will provide the foundation for a future conservation project to reverse the decline of these butterfly species in the Blackdown Hills AONB.
An update given at the AGM (Nov 2019)
2019 saw the start of our Blackdowns project. With some financial support from Devon Branch we employed consultants to identify all sites with records of Marsh Fritillary and Small Pearl-borderd Fritillary and where possible arrange access.
In all, eleven sites in Somerset and seven in Devon had a total of 31 survey visits to seek foodplants, adults or larvae. Marsh Fritillary was recorded at one site while eight sites appeared suitable for them. Small Pearls were also confirmed from one site while 13 sites had potential.
These will be resurveyed in 2020 and in 2021 we will search for Wood White and Duke of Burgundy.
Much time also went into monitoring habitat for Duke of Burgundy at Quants where the species has not been recorded since 2016. With the consultant’s advice, a new grazing exclosure was set up to compare vegetation responses to two different grazing regimes and a no-grazing area through the season.
In the light of this and after discussion with Forestry England, which is the landowner, and with the Grazing Group we have negotiated a different regime for next year; grazing will start later, with fewer cattle, and we will monitor its effects on vegetation and foodplants.
A lot of folk were involved in these two projects and particular thanks are due to Nigel Cottle, John Marshall, John Connolly and Tony and Anna Speiss for the considerable field time they have put in.
November 2020 (Report at online AGM)
Due to Covid-19 restrictions, the Blackdowns Project was put on hold apart from a successful Marsh Fritillary web-search at the one known Somerset site. Two large and apparently suitable sites were exhaustively searched in the flight season and also for webs but with no success, though there was a report from a site just in Devon.
We have engaged Wessex Environmental Associates, who did the planning of the first stage of the project, to help us carry the project forward in 2022 with the aim of deciding whether and how Marsh Fritillary and Small Pearl-bordered Fritillary populations can be recovered and sustained in the landscape.
At the Quants site, searches again found no evidence of Duke of Burgundy. The effect on vegetation and food plant condition under a different grazing regime was monitored and we hope we are approaching a point where we may be able to plan a reintroduction with a realistic prospect of success.