Northern Brown Argus Project

The Northern Brown Argus (NBA) is one of the few butterflies in our region which occurs as a sub-species in the North East of England and very few other localities in the UK.  Differentiated from its much more common, southern cousin, the Brown Argus by a pale spot on the fore-wing, it is also rather more fussy with its larval food and is not understood to eat anything other than Common Rock-rose.  Its distribution is restricted to the limestone outcrops where Rock-rose occurs in County Durham and its most northerly, known, location is in Wearside on the edge of Sunderland. 

The butterfly and its habitat were comprehensively surveyed in 2006 by Butterfly Conservation staff Dave Wainwright and Sam Ellis.  At this time, the NBA was known to be in decline and absent from some of the 42 previously known locations, with some of its habitat in relatively poor condition due to rank vegetation encroachment.  It is understood that some of the landowners on which NBA occurs implemented the habitat management advice included in the 2006 Wainwright and Ellis report.  However, there has been no follow-up survey done and the North East England Branch Committee of BC would like to undertake and expand the original survey with the assistance and support of the NE branch members.

To start the project, Dave Wainwright has agreed to run an initial training session on the 4th January 2013.  Anyone interested in becoming involved (no expertise required) is welcome to join in.  We are meeting at 10am at Rainton Meadows (Durham Wildlife Trust HQ off the A690, Sunderland to Durham Road).  This initial session will last approximately 3-4 hours.  We intend visiting one or two sites close by to understand how to assess the quality of the NBA habitat and what habiatat management is required to make it more suitable for the butterfly.  In the summer, we will survey as many of the 42 sites as possible for the presence or absence of the adult butterfly and its eggs and then in the winter, begin an annual programme of vegetation management which may include growing and planting Rock-rose where appropriate.  The ultimate intention of this project will be to greatly enhance the butterfly's habitat and survival prospects.  We very much hope that as many of our members will want to get involved in some way (large or small) with what will be an important conservation project in the region.

If you would like further details, please email, michaelsharris@talktalk.net voluntary Conservation Officer, for the branch in County Durham.  As the project develops, updates will be posted on this page.

Photo: Mating Northern Brown Argus. Copyright Tim Nelson.