Mountain Ringlet Surveys in 2009
Introduction |
Distribution Map
(Click for bigger image) |
The Mountain Ringlet (Erebia epiphron) is a rare UK butterfly being confined to montane habitat between 350 & 900 m in the central highlands from Ben Lomond in the south to Creag Meagaidh /Glen Roy in the north and from Glasdrum/Glencoe, Argyll in the west to Schiehallion in central Perthshire in the east with two known colonies further east in the Cairngorms National Park: Glen Doll & Glen Feshie. This distribution amounts to just 50 10 km squares in Scotland which makes it much rarer than the iconic birds of the Scottish mountains such as the Ptarmigan & the Golden Eagle.
Given the presence of large areas of land from 350-900 m outside the known range, there must be a factor other than altitude which explains this limited distribution of Mountain Ringlet. This aspect of Mountain Ringlet ecology is being investigated as part of a research project into montane invertebrates being funded by Scottish Natural Heritage, the John Muir Trust, the National Trust for Scotland & Butterfly Conservation during 2008 & 2009. Previous research suggests that it is a combination of damp Mat-grass grassland and abundant nectaring plants which provides good habitat for Mountain Ringlet.
In 2008, committee member, Andrew Masterman, was contracted to do surveys of Mountain Ringlet and to encourage volunteer surveys on Scottish mountains. The main findings of these surveys are presented below.
|
 |
Findings of 2008 Survey | Observations in 2008
(Click for bigger image) |
Fifteen different mountains were surveyed for Mountain Ringlet and the abundance of nectaring plants recorded on them during the contract work. Volunteers recorded Mountain Ringlet on a further five mountains. Mountain Ringlet was found on thirteen mountains: Leana Mhor, Glen Roy; Meall Cuhahan, Ben Nevis; Meall nan Tarmachan; Ben Lui; Beinn Churalain/Glasdrum;Beinn Sguilard; Glencoe near the Devil’s staircase; Creag Meagaidh; Sgurr a Mhaim; Beinn Chaorach & Cam Chreag near Tyndrum; Ben Lawers; & Schiehallion. Mountain Ringlet was not found on the following six mountains: Ben Nevis around the tourist path; Ben Odhar, near Tyndrum; Stob Ghabhair nr Bridge of Orchy; Drumochter; Ben Lomond; & Beinn Heasgarnich in Glen Lochay. The map on the right shows the Mountain Ringlet records recorded with a GPS device during the contract survey in dark blue and a few records provided by volunteers in green. Click on the map for a bigger image and more detailed local maps.
Surveys of the abundance of nectaring plants of adult Mountain Ringlet and of the abundance of Mat-grass, the food-plant of the caterpillars, showed that Mat-grass was generally the dominant grass from 400 m upwards and that both Mat-grass and the nectaring plants increase in abundance from 400 m to 700 m and then decline above this, such that above 900m, Mat-grass is patchy and unhealthy looking and there are few nectaring plants. The following five nectaring plants are considered good indicators of Mountain Ringlet Habitat: Heath Bedstraw; Wild Thyme; Tormentil; Meadow Buttercup; & Alpine Lady's Mantle.
|
 |
Description
The Mountain Ringlet is a small dark brown butterfly with orange bands containing black spots on both upper and underwing surfaces. Distinctive features of this small butterfly are the white legs and antennae which contrast strongly with the dark body.
The Mountain Ringlet can be confused with the closely related Scotch Argus (Erebia aethiops) which is a somewhat larger dark butterfly which also has orange bands on the upperwings containing black eyespots and which is also found in the Scottish Highlands. A distinctive feature of the caledonia sub-species of the Scotch Argus which is the sub-species which occurs in Scotland is the narrowing of the orange band on the upper forewing between the two anterior eyespots and the single posterior eyespot. Also, the Scotch Argus flies somewhat later in the summer commencing about the 20 July but this overlaps with the latter part of the flight period of the Mountain Ringlet which can lead to mis-identification of the much rarer Mountain Ringlet.
Survey Aims
Building on experience gained in 2008, the survey methodology in 2009 has been modified and simplified which should make it less time-consuming. But until it has been tried and tested, it remains to be seen how easy it is to do. It is hoped that volunteers can get involved to survey different mountains and to contribute to this current research into the beautiful Mountain Ringlet. The survey work has two main aims.
- to record the number of Mountain Ringlet seen within 1 km squares which have south facing slopes with an altitude range of 400-900 m
- to record the incidence and abundance of five flowering plants and Mat-grass within 1 km squares which have south facing slopes with an altitude range of 400-900 m to produce a total score which represents the suitability of land within a 1 km square for Mountain Ringlet.
When & Where to Do?
As mentioned in the Introduction, previous research has shown that good habitat for Mountain Ringlet is provided by a combination of damp Mat-grass grassland and abundant nectaring plants. A major aim of survey work in 2009 is to collect vegetation data on mountains both within and outside the known range of Mountain Ringlet to verify this link between herb-rich Mat-grass grassland and Mountain Ringlet. So any mountain within Scotland with an accessible south-facing aspect in the altitude range of 400-900 m is suitable for surveying and data from mountains in the north-west of Scotland would be of particular interest as these mountains have more Mat-grass than those in the Grampians which are dominated by Heather and Bluberry. These vegetation surveys can be done anytime from early June to the end of August when the five species of nectaring plants are in flower. And sunny weather is not required.
If you want to record Mountain Ringlet, you need to do surveys on mountains within the central Highlands (see Introduction & Distribution map above) between 25 June to 20 July which is the peak flight period and which avoids the flight period of the similar Scotch Argus which commences about 20 July. A sunny day is required for Mountain Ringlet surveys as they don't fly in cloudy weather. One aspect of recording Mountain Ringlet is to ascertain whether colonies at lower altitudes are becoming extinct due to climate warming as suggested in two papers. To investigate this issue, surveys during late June and early July are required as this is early in the flight period when Mountain Ringlet is found at lower altitudes.
A 'hit list' of 1 km squares to be surveyed has been prepared which you can print out (click here to download): there are 303 suggested squares within the known range of Mountain Ringlet and 56 squares outside the known range.
Methodology for Recording Mountain Ringlet
Either, simply count all Mountain Ringlet seen within a 1 km square and provide six figure grid references to represent where you saw them and note this on the recording form or preferably use a GPS device and record each Mountain Ringlet seen with a waymark - this enables both a precise position and precise altitude to be determined. Some standard settings are required: set position to be recorded as British National Grid and altitude in metres. Once your track and waymarks are downloaded to your computer, please save as a text (TAB delimited) file or Excel worksheet without editing, and
. But the Mountain Ringlet Survey Forms should be completed too and sent to this email address or posted to the address on the form.
Methodology for Vegetation Surveys to produce a score for Mountain Ringlet Habitat
The aim of this survey work is to produce a score out of a maximum of 20 for each 1 km square on south facing aspects of mountains which measures the quality of the land for Mountain Ringlet. A GPS device would be very helpful for this work as you need to know where you are in relation to specific 1 km squares. To adequately survey a 1 km square, a walk 500 to 750 m long within a square should be done with the aim of surveying several squares on the south facing slope of a mountain by doing a circuit. A pair of binoculars would be helpful in scanning vegetation from a distance.
1) Score to determine extent of land with suitable altitude range and aspect within a 1 km square:
NB: ha = hectare and there are 100 hectares in a 1 km square.
- less than 10 ha S-facing slopes from 400-800 m = 0
- 10-30 ha S-facing slopes from 400-800 m = 1
- more than 30 ha S-facing slopes from 400-800 m = 2
2) Score to determine that Mat-grass grassland is present in the 400-800 m altitude range within a 1 km square (i.e in the area estimated in 1) above):
- less than 10 ha Mat-grass grassland with Mollinia/Heather/Blaeberry/Rock/Other dominant = 0 (most squares within the Grampians would probably have this score as Heather and Blueberry are dominant here).
- 10-30 ha with Mat-grass grassland = 1
- more than 30 ha with Mat-grass grassland = 2
3) Score to note presence/absence of sheep grazing: sheep grazing is known to favour a sward dominant in Mat-grass.
- no sheep grazing = 0
- sheep grazing = 1
4) Scores to record the abundance of the nectaring plants: Tormentil; Heath Bedstraw; Wild Thyme; Alpine Lady’s Mantle; & Meadow Buttercup. A minimum of five gullies (with or without streams) should be investigated and the grassland outside gullies also assessed. A higher density of flowering plants is usually found within gullies, especially gullies with streams but on south-facing slopes outside gullies, Wild Thyme, Heath Bedstraw and Alpine Ladys Mantle may form carpets of flowers above about 600 m and Tormentil and Meadow Buttercup may be scattered amongst Mat-grass grassland.
Score the abundance of each of the five nectaring plants by looking in dry gullies and gullies with streams and by looking at the vegetation outside gullies:
0 = absent 1 = present within gullies 2 = abundant within gullies 3 abundant within gullies and large areas outside gullies
The following pro-forma should be used to record the survey data Mountain Ringlet Survey Form., one for each 1 km square surveyed. A list of mountains and 1 km squares to survey will be posted here in due course.
The following are photographs of Mat-grass and four of the five nectaring plants (we all know what Meadow Buttercup looks like!) and this document enables you to print them out to take out into the field.
Mountain Safety
A moderate level of fitness is required for this survey which involves ascending and descending mountain slopes over a number of hours if several 1km squares are to be surveyed. Also, the standard mountain safety advice applies.
- TAKE map, compass/GPS, mobile phone and/or whistle, sun hat, watch & survival bag.
- DO let someone know your expected route and expected time back and what to do if late (ie a 'buddy' system).
- DO wear stout footwear, preferably walking boots
- DO take warm clothing and waterproofs as conditions are likely to be colder and windier up a mountain even on warm sunny days and because conditions can change
- DO take food and drink
- DON'T attempt to survey along waterfalls, scree slopes or above crags or steep slopes
- DON'T put yourself or anyone else at risk during this survey
If you prefer to send in more limited data by email, then please
with basic information including 6 figure OS map reference, date and counts of Mountain Ringlet.
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 hours you have worked, we can claim your time as match funding against our grants.
Survey Checklist
If you would like to participate in this Mountain Ringlet Survey, there are a few documents you need to print out which are listed below:
References
- Franco, Aldena M. A., Hill, Jane K., Kitschke, Claudia, Collingham, Yvonne C., Roy, David B., Fox, Richard; Huntley, Brian; Thomas, Chris D. 2006 Impacts of climate warming and habitat loss on
extinctions at species’ low-latitude range boundaries Global Change Biology, 12. 1545-1553
- 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)
- Hill, J. K., Thomas, C. D., Fox, R., Telfer, M. G., Willis, S. G., Asher, J. and Huntley, B. 2002. Responses of butterflies to twentieth century climate warming: implications for future ranges Proceedings of the Royal Society 269(1505): 2163–2171.
Written by Andrew Masterman
Homepage
