Northern Brown Argus

Northern Brown Argus (Aricia artaxerxces)

 

The Northern Brown Argus is a nationally scarce species and one of Scotland’s most threatened butterflies.

The butterfly mostly inhabits flower-rich grasslands either at the coast or in the uplands. The presence of Common Rock-rose is essential as this is the sole foodplant of the butterfly’s caterpillar. Sadly species-rich grasslands are under threat, having declined nationwide by over 97% in the last century.

Surveys in Scotland 2024

BC Scotland are carrying on with an extensive survey of Northern Brown Argus sites in Scotland. With 564 known or suspected colonies, it is a big and ongoing task! However, excellent progress has been made over the last few years with 339 colonies now visited or mapped.  

The surveys began in Borders back in 2016, with the survey expanding in recent years to other parts of Scotland.  Recent data from the State of Butterflies 2022 report suggests there has been a decline in distribution of  Northern Brown Argus in Scotland so these surveys will help to show if the decline is real or linked to recorder effort. Surveys in the Borders have highlighted the threat from inappropriate new woodland creation schemes and we’re concerned that this issue may be affecting Northern Brown Argus colonies elsewhere in Scotland too.  

Efforts last year were boosted by the Species on the Edge project which is coordinating surveys efforts for Northern Brown Argus in three coastal areas (Solway, Aberdeenshire and Easter Ross/Sutherland) supported by local project officers.  

Training workshops

We are looking for willing volunteers to take on a local site to survey for Northern Brown Argus.

To help encourage surveys this we will be offering a free zoom training workshop followed by some optional field workshops.

The online training workshop will be held via Zoom on Wednesday 19th June at 7pm. A recording of the workshop will be available for anyone who can not attend. 

Register for the online workshop here

There will also be several organised field trips and walks to see Northern Brown Argus - see details below.

Thursday 20th June: Old Shandwick - Date TBC. Field training on identification and survey techniques for the elusive Northern Brown Argus and how best to record butterflies and moths along the coast. Leader name and further information: Tracy Munro Email: @email 

Friday 21st June: Borgue & Brighouse Bay - Indoor morning session with a focus on NBA identification and survey techniques. Afternoon field trip to Brighouse Bay to see a range of species in the field and practice survey skills.

Sunday 30th June: St Abbs Head NNR - A walk round St. Abbs Head NNR to see Northern Brown Argus and perhaps Grayling butterfly. 

Friday 5th July: Tummel Shingle, near Pitlochry -  Join us for this event where we will learn how to identify and record the butterfly adults, and look for their eggs.

Saturday 6th July: Rosemarkie Cliffs - A walk along the shore at the base of the cliffs. There is a path most of the way, but the terrain is uneven. In 2014, twelve species of butterflies were seen on this walk. Leader name and further information: Pete Moore  Email: [email protected]

Survey locations map

The Google map below shows Northern Brown Argus sites that we have identified as survey priorities for 2024.

If you zoom in and then click on the marker, information on that site will appear in a box. It is also possible to navigate to different parts of the country.

If you are willing to survey any of these sites please contact David Hill via dhill@butterfly-conservation.org to receive further information on the site.

Surveys are best undertaken between late-June and the end of July. Surveys can take place in dull weather as presence of the butterfly is most easily confirmed by searching for the conspicuous eggs. 

For sites along the Moray, Aberdeenshire and Solway Coasts, a Species on the Edge project officer will be available to support survey efforts. 

Links for more information

Butterfly Conservation UK

Northern Brown Argus