SMALL DARK YELLOW UNDERWING (Coranarta cordigera)
Small Dark Yellow Underwing can appear very similar to its close relative the much more common Beautiful Yellow Underwing. However, when at rest on rocks and posts, or when nectaring on moorland flowers, it is identifiable by the white markings on a dark background as well as the yellowy-orange underwings. Bearberry Arctostaphylos uva-ursi is the sole larval foodplant. Adults can be seen from mid-April until the first week of June, at altitudes of 200-650m. It occurs in the Cairngorms, eastwards to parts of Aberdeenshire and Angus and south to Highland Perthshire. The only record north of the Great Glen is from Glen Affric.
A survey weekend, based in Kingussie, was held in the spring of 2014 to target recording at known sites as the species had not been recorded in Scotland for three years. This resulted in over 50 attendees and Small Dark Yellow Underwing being recorded at three sites, one being a new location.
Pupa reared from eggs laid by a female caught in 2014 have been sent to Dr Joe Burman at Canterbury Christ Church University to identify the chemical composition of the moth’s pheromone.
Informal management advice given to a number of estates to promote the importance of arctostaphylos heath.
Continue to encourage visiting and local moth-ers to look for Small Dark Yellow Underwing by day-time searches for flying or resting adults. Trial the Small Dark Yellow Underwing pheromone if/when available.
Intend to work more closely with the Cairngorms National Park Authority to help deliver targeted management advice. Investigate the possibility of undertaking volunteer work parties to enhance habitat at sites where scrub is known to be an issue.
Continue to develop a useable pheromone to assist with survey and monitoring in collaboration with Dr Joe Burman at Canterbury Christ Church University.
DARK BORDERED BEAUTY (Epione vespertaria)
Annual surveys are conducted to help determine the extent of the population. This has resulted in a number of new sub-colonies being discovered in Deeside.
All occupied Scottish sites are monitored annually by Butterfly Conservation Scotland volunteers and, over the last three years, with the assistance of RSPB members of staff on sabbatical.
One site is being managed under SRDP, all other sites are managed with the assistance of Butterfly Conservation Scotland volunteer work parties clearing back scrub to encourage low-suckering aspen.
Butterfly Conservation Scotland is working closely with Highland Aspen Group and Coille Alba to propagate local aspen to help increase aspen connectivity, particularly within the cairngorms. This has included ground-truthing of aerial images specifically taken to help map the current aspen resource.
Surveys & Monitoring
Sites in Deeside and at Insh Marshes are deemed to be in suitable condition and management is not currently required. Habitat management is being focussed at the Grantown site where a combination of planting, protection and creating clearings are planned in order to increase the aspen resource, improve connectivity and enhance the habitat for Dark Bordered Beauty.
Dr Joe Burman is keen to develop a synthetic pheromone for Dark Bordered Beauty but this is reliant on rearing the species from eggs obtained from wild caught females or from larvae found in the field. Permission to collect this material from Insh Marshes is being sought from SNH
Links for more information
Butterfly Conservation UK Dark Bordered Beauty factsheet