Dingy Skipper Surveys 2009

Introduction

The Dingy Skipper is currently the rarest of the 34 butterfly species found in South West Scotland. It is classed as a national BAP priority species and is one of 6 butterflies listed on the Scottish Biodiversity List. The Dingy Skipper has suffered significant declines throughout the UK and in Scotland is confined to just two areas: predominantly coastal sites in the South West and around the Moray Firth. The reasons for the decline of this species are not entirely clear as the food plant Bird's Foot Trefoil (Lotus corniculatus) is pretty widespread. Changes in land use such as agricultural intensification, the cessation of coppicing in woodlands, habitat succession, and the recent policy of developing brownfield sites appear to be major factors in the loss of this species. At the present we have very little information concerning the status of this important species in South West Scotland.

A number of sites have been identified where the butterfly was recorded in the past (see table below). In order to conserve the species we first need to know its current distribution and the size of existing colonies. At some sites only one to two individuals have been seen, so it is important to confirm that these sites contain breeding colonies rather than just vagrants passing through. This will require further visits and habitat assessment. For detailed conservation planning and action, it is important to identify where on these sites the dingy skipper is breeding. It is hoped that data collected in this survey can be used to establish suitable conservation strategies to protect this little butterfly.

Credit: Jim Black

Credit: Jim Black

Credit: Keith Warmington

Field Trip Safety

A moderate level of fitness is required for this survey.

• Ideally TAKE a map of the area to be surveyed, a compass/GPS, mobile phone and/or whistle.
• DO wear stout footwear, preferably walking boots
• DO wear suitable clothing, a hat and sun block in sunny weather
• DO take food and drink

Methodology

If you see any Dingy Skippers, it would be appreciated if you could complete a Dingy Skipper survey form which records habitat characteristics including the abundance of larval food plants and nectar plant species, whether bracken or scrub is invading the site, as well as numbers of butterflies. And of course, record any other butterflies that you come across.

Photographs and/ or a sketch of the site showing where you searched and features of interest would be fantastic.

Description & Ecology

The Dingy skipper is a small (wingspan 27-34 mm) well camouflaged butterfly with grey and brown wavy-patterned wings. Both sexes are similar, although females tend to have a darker background colour. The adults are short lived and quickly begin to look quite worn.

During sunny weather it can often found basking on bare patches of ground with wings wide open, while in the evening it may be found perching on the tops of dead flower heads with its wings curved back in a very distinctive posture. The dingy skipper is a fast flyer and the males will interrupt sunbathing to chase any potential mates or intruding rivals with a rapid buzzing flight.

After emerging during May/June males set about defending temporary territories within their colony and await passing females. Adults tend to be very sedentary and rarely move very far from existing colonies. Females search for plants of Bird's Foot Trefoil (Lotus corniculatus) growing in warm sheltered nooks or spreading over bare soil/stones on which to lay their round greenish-white eggs. The eggs are generally laid singly on the upper surface of young leaves within 2.5 cm of the shoot tip, but occasionally two or more eggs may be found on the same plant. The female generally chooses shoots growing away from the main plant especially those spreading over bare ground or rocks, or dead fine-leaved grasses. Rocks and bare ground will absorb and hold more warmth than surrounding vegetation, which may enhance development of the egg and larvae. Plants in sheltered hollows will be chosen over exposed plants. The surrounding vegetation tends to be short (under 15cm in height). Eggs and larvae are very occasionally found on Greater Bird's Foot Trefoil (Lotus pendunculatus) and Horseshoe Vetch (Hippocrepis comosa).

Credit: Scott Shanks

Credit: Keith Warmington

Credit: Keith Warmington

After approximately 5 days the eggs turn orange and hatch after about 2 weeks (9-12 days) depending on the weather. The newly hatched caterpillar is green with a dark green line down its back and a dark head and hides within a silk tent made by spinning leaves of the food plant together. The larvae are slow growing and normally only one brood is produced each year (very occasionally a partial second brood is reported during hot summers). They feed until fully grown in August/September, when they spin more leaves together to form a hibernaculum in which to spend the winter months. Pupation occurs the following April in the hibernaculum without further feeding.

Colonies tend to exist on south-facing warm sheltered sites with abundant Bird’s-Foot Trefoil (or occasionally Greater Bird’s-Foot Trefoil) and sparse sward/grass covering and plenty of bare patches for basking in the sun. Patches of taller vegetation or light scrub may be used by the adults as roosting sites. Sites often have bare ground resulting from grazing or landslips, footpaths or rocky out-croppings .

When To Do Survey

In South West Scotland adults can be found on the wing during May and June in one protracted brood, with numbers peaking at the start of June. Following warm spring weather individuals may emerge at the end of April. In 2007 and 2008 the first sightings of the year were on the 28th of April and the 14th of May respectively.

The best dates for this survey are from the 9th of May through to the 21st of June, but a week earlier or later may also prove fruitful. If possible warm sunny days should be chosen for the survey when adults will be most active. In overcast conditions adults may be found roosting on grass stems in a head-down position. On dull days it is still possible to survey for breeding habitat at the sites and to look for eggs and young larvae. The ideal time to search for eggs would be the first 3 weeks of June.

It would also be appreciated if a volunteer timesheet could be completed if you participate in this survey. If you let Butterfly Conservation know about the volunteer hours you have worked, we can claim your time as match funding against our grants.

Taking photographs of sites with a digital camera is a great way of providing information on the state of a site. A photograph must be linked to a grid reference, site and date, so please record these data in a long descriptive file name and

Sites in Ayrshire and Dumfries & Galloway to be surveyed for Dingy Skipper

The map below shows the 19 sites requiring visits in May/June 2009. If you place your mouse over the site name, a little window with the site name will appear and if you click on the site name, a 2 x 2km OS map will appear in a new window. Click here for a Word document containing the map and table below which you can print out and take out into the field.

 

Site Name	Description	Grid Reference (Click for OS map)
Pinbain Burn, Lendalfoot	Steep flower-rich hillside on basic rock next to burn and coastal path north to Kennedy's pass. Park at layby on A77 north of Lendalfoot. OS Maps 76 or 317	NX138916
Bennane Head, Ballantrae	Bennane Lea to Balcreuchan Port. Steep coastal path, undercliff and coastal grassland. Park on old A77 at NX092859. OS Maps 76 or 317	NX091868
Currarie Port,South Ayrshire	Herb-rich grassland on basic rocks and gully with oaks. Park at side of farm track at NX063770. OS Maps 76 or 317	NX057780
West Tarbet, Mull of Galloway	Coastal grassland path along cliffs on West side of Mull of Galloway. Carpark at RSPB reserve at NX155304. OS Maps 82 or 309	NX135309
Torrs Warren, Luce Bay	Coastal forest plantation next to dune grasslands and heath. Beware of venturing out onto mudflats. Car park at NX143563. OS Maps 82 or 309.	NX157558
Elrig, Luce Bay	Area around Elrig Loch about 1 mile north of Elrig. OS Maps 82 or 311	NX327492
St Ninians Cave, Port Castle Bay	Coastal habitat and cliffs. Park in Kidsdale (near St Ninians Cave) at NX432366. OS Map 83 or 311	NX432366
Garlieston Bay	Coastal habitat. Rocky shore and woodland on north-side of the bay. Park at Garlieston villiage. OS Maps 83 or 311	NX487467
Kilsture Forest, Sorbie	Forest Walks in woodland north of Sorbie. Carpark at NX441484. OS Maps 83 or 311	NX440490
Carrick, Gatehouse of Fleet	Rocky Coastal habitat arround Carrick and Sandgreen,facing Fleet Bay and the Islands of Fleet. OS Maps 84 and 312	NX576504
Dalbeattie Forest	Forest Roads through Mature Coniferous plantation.Lovers Loup on South face of Barscraig hill is good site.Also try Forest roads on Fairgirth Hill above Sandyhills Bay at NX891562.OS Maps 84 and 313	NX865569
Burrow Head, Isle of Whithorn	Coastal cliffs and grassland. Pathway from Isle of Whithorn down to Burrow Head. Parking at Isle of Whithorn NX479361. OS Maps 83 and 311	NX448343
Rascarrel Bay	Coastal footpath from Balcary Bay to Rascarrel Bay. Park at NX820494. OS Maps 84 or 313	NX809483
Rockcliffe to Portling	Coastal walk from Rockcliffe to Castle hill Point. Scenic footpath carries on towards Portling. Good habitat along here. Park off Colvend to Rockcliffe Rd at NX851535. OS Maps 84 and 313	NX854526
Auchenfad Hill, Mabie Forest	Conifer plantation hillside with forestry Road. Park either at Mabie Forest carpark at NX949711 or possibly on Forest track. OS Maps 84 or 313	NX950696
Mabie Forest	Forest Roads through coniferous woodland of Mabie Forest.Butterfly Conservation reserve.Carpark at NX949711. OS Map 84 or 313	NX927704
Stroan Loch	Grasslands and paths near Stroan Viaduct and Loch. Park at picnick site NX649700 or Mossdale NX660705. OS Maps 77 or 320	NX644701
Craig Forest, near New Galloway	Forest Roads through Craig Forest Plantation, east of Corse, near New Galloway. OS Maps 77 or 320	NX683763
SWT Feoch Meadows	SWT reserve.Grasslands and small rocky gorges. Turn left off A714 about 1.5 miles after Barrhill Villiage into the Killantringan Farm track and take the left fork up to the car park.OS Maps 76 or 317.	NX268821

Written by Scott Shanks

References

• Futter, K., Sutcliffe, R., Welham, D., Welham, A., Rostron, A., MacKay, J., Gregory, N., McCleary, J., Tait, T., Black, J. & Kirkland, P. 2006. Butterflies of South West Scotland. Argyll Publishing. (see Atlas page)
• Asher, J., Warren, M, Fox, R., Harding, P., Jeffcoate, G., Jeffcoate, S. 2001. The Millennium Atlas of Butterflies in Britain & Ireland. Oxford University Press.
• Fox, R., Asher, J., Brereton, T., Roy, D., Warren, M. 2006. The State of Butterflies in Britain and Ireland. Pisces Publications.
• Tomlinson, D. & Still, R. 2002. Britain’s Butterflies. WILDGuides
• Bourn, N.A.D, Jeffcoate, G. E. and Warren, M. S. 2000. Dingy Skipper Erynnis tages species action plan. Butterfly Conservation
• Slater, M., February 2008. Warwickshire butterfly conservation newsletter.