MOTHS OF THE BURREN – Philip Strickland
The Burren is a karst limestone region in north Co. Clare which is renowned for its remarkable assemblage of plants and animals. The region has long been known as an area that supports many rare Irish plants however it is only in comparatively recent years that The Burren has attracted the interest of lepidopterists. It is now known as a very important area for many of our rare butterfly species including Pearl-bordered Fritillary (Boloria euphrosyne), Brown Hairstreak (Thecla betulae) and Wood White (Leptidea sinapis).
The study of moths of the Burren really only began after the discovery in 1949 by Capt. W. S. Wright of the Burren Green (Calamia tridens), a distinctive green moth. This discovery created a lot of interest from British lepidopterists and resulted in many visits to the area. The Burren then became known as an important site which resulted in many subsequent exciting discoveries in this field of study. In 1991 another UK lepidopterist Peter Forder recorded the Irish Annulet (Odontognophos dumetata ssp hibernica) for the first time in Ireland while trapping for the Burren Green.
The Burren is now regularly surveyed by Irish and UK lepidopterists with exciting discoveries continually being made. Moth trapping using mercury vapour and portable actinic traps allows more extensive coverage especially in areas that were previously difficult to survey. In recent times there has also been an upsurge in interest in the study of moths and this has resulted in many more amateur naturalists recording their sightings. Many of these records are now digitised and are accessible over the internet thus allowing for easy access to anyone who is interested.
So why is the Burren so special?
It basically boils down to quality of habitat and to sympathetic management. The limestone pavement is intermixed with calcareous grassland and hazel scrub and this allows for a vast array of plants to grow. Suitable grazing methods and the lack of fertilizers allow these plants and the insects associated with them to thrive. So whether walking through The Burren during the day or examining the contents of a moth trap left out overnight the sheer numbers of moths and the variety of species is astounding.
There follows some images and a brief description of some of the Burren Specialities. Let’s start with the iconic species of the Burren, the Burren Green.
Burren Green (Calamia tridens). Although highly distinctive with its bright green colour this moth is nocturnal and rarely encountered during the day. It is attracted to light and is commonly found in moth traps in any suitable habitat throughout the Burren region from Mid-July to the end of August. The larvae feed on Blue Moor-grass.
Speckled Yellow (Pseudopanthera macularia). This aptly named pretty day flier can be seen in May and June flitting in and around the Hazel scrub and may be mistaken for a butterfly. It is found in the southern half of Ireland and is common locally in the Burren.
Transparent Burnet (Zygaena purpuralis). Confined to the limestone areas in the west of Ireland with The Burren its stronghold. It is day-flying species and it can be easily encountered in June during warm weather, particularly in sunshine. During dull or wet spells they can often be seen sitting on flowerheads or surrounding vegetation and can easily be approached and photographed.
Least Minor (Phothedes captiuncula). Found only in the Burren and similar limestone areas in neighbouring Galway, this Irish subspecies is named tincta and is brighter and more strongly marked than the nominate race. It has an extended flight period from late May until the end of August. It can be seen in sunshine, flying wildly and erratically and diving deep into vegetation though it is not commonly found. Its larval food plant is Glaucous Sedge.
Dew Moth (Setina irrorella). This moth is only found in Clare and Galway but can be fairly common in rocky areas of the Burren from mid-May to mid-July. Usually the male flies both during the day and night while the female is strictly nocturnal. The larvae feed on lichens found on the limestone.
Juniper Carpet (Thera juniperata). This rare moth has only been recorded in a few different sites in Ireland including The Burren though its flight time of October probably means that it under recorded. It is best looked for as a caterpillar on the food plant Common Juniper which occurs in its prostrate form in this region.
Irish Annulet (Odonthognophos dumetata). This moth is extremely rare and has only been found in a couple of 10k squares in the Burren and nowhere else in Ireland or Britain. Sub species hibernica is distinct from ssp. dumetata, from mainland Europe, which is much browner. It flies at night in August around its larval food plant Purging Buckthorn.
Small Eggar (Eriogaster lanestris). The adult moth flies at night during late February and March so it is seldom seen. Most records for this species are of the larval webs which are fairly conspicuous in Blackthorn and Hawthorn during mid-summer.
Lackey (Malacosoma Neustria). This species is usually seen in larval form between April and June when the webs are conspicuous in many Hawthorn hedges and bushes throughout the Burren. The caterpillars openly bask in groups and are easily identified by the attractive blue colour. The adult moth, which flies at night during July and August is not nearly as brightly coloured.
Heath Rivulet (Perizoma minorata). This species is confined to the Burren where it is still fairly rare. It flies in August and it is usually nocturnal though it has been recorded flying on hot, sunny afternoons. The larval foodplant is eyebright.
Straw Belle (Aspitates gilvaria). This is another moth that is well established in the Burren with very few records outside this region. The Irish race has been given the subspecies name burrensis. While it is a night flier it can easily be disturbed while walking through calcareous grassland during the day. It has a range of food plants which are common in this type of habitat including trefoils, thyme, Creeping Cinquefoil and Wild Parsnip.
Small Argent and Sable (Epirrhoe tristata). This attractive day flier can be seen around its foodplant Heath Bedstraw. Care must be taken as it resembles the more common Common Carpet which can also be active during the day. It can be seen right throughout the summer having a second generation on the wing in August.
Wood Tiger (Parasemia plantaginis). While this attractive species can be found throughout Ireland it can be regularly encountered by day in June and July throughout the Burren. It cannot be confused with any other species as it is seen flying erratically in low vegetation. It has a range of herbaceous food plants including Salad Burnet, Common Rock-rose, Greater and Ribwort Plantain and Goundsel.
Beautiful Brocade (Hadena contigua). While this moth occurs throughout Ireland, it is seldom seen in such numbers as when opening a trap in the Burren, given the right conditions. As its name suggest it is a very attractive species with variable colouring from grey brown to bright pink. It has a wide range of larval food plants and the adult is on the wing from May until July.
Small Elephant Hawk-moth (Deilephila porcellus). This species occurs all around the coast of Ireland however in The Burren it appears to penetrate further inland and is found throughout the region. It is an impressive creature being more brightly coloured than its larger relative the Elephant Hawk-moth and can occur in large number in the moth trap. It flies from May until July with the caterpillars feeding on a range of bedstraws.
The smaller (micro) moths are less well known and less studied than their larger (macro) counterparts so there is huge scope for further study of micro moths throughout Ireland but especially in the Burren. Species new to Ireland are still being regularly discovered from this region as a direct result of additional fieldwork. Many micro moths are known by their scientific names. Some more notable micro moth species are as follows:
Lampronia pubicornis. This is a rare species with very few Irish records. It feeds on Burnet Rose and is on the wing in late May and early June.
Hypercallia citrinalis. This stunning little pink and yellow moth is confined to this region. Larvae feed on milkworts.
Pancalia schwarzella. While nearly all records for this rare species are from the Burren a single specimen has been recorded at our Crabtree reserve in Lullybeg in 2014. It flies early in the year from late April until mid-June and the larvae feed on violets.
Clepsis rurinana. There have only been eight records of this moth in Ireland with all but one occurring in the Burren. That single record outside the region was also from the Crabtree reserve in Lullybeg. The moth is on the wing from mid-June to mid-July and the larvae feed on a number of different trees and shrubs.
Anania funebris. This small moth is instantly recognisable with its large white spots on a dark background. It is fairly common in the region and flies by day where its larval food plant, Goldenrod is found.
Catoptria pinella. This is one of the Crambids or grass moths and it quite attractive with its russet and white markings. It is found along the western seaboard in damp habitat where the larvae feed on a range of grasses.
Pyrausta sanguinalis. With its bright purple and yellow markings this species is easily recognisable. It is common in the Burren and flies by day while also attracted to light at night. The larvae feed on Wild Thyme.
Acleris permutana. This rare species is only found in the Burren in Ireland where it has been recorded from just two 10K squares. It closely resembles the Garden Rose (Tortrix acleris variegana) which is commonly found throughout Ireland. The moths fly in August and September and are nocturnal. The larvae feed on Burnet Rose.
Merrifieldia tridactyla. Plume moths are very distinctive with their unusual ‘T’ shape and the Burren is home to several species from this family. This moth is another Wild Thyme feeder and is quite scarce and local.
Finally, as described above some moths found in The Burren have a different appearance from populations found elsewhere. The Least Minor, Straw Belle and Galium Carpet are examples of this phenomenon. These distinctions create much interest and offer scope for further study. While these differences do not always confer sub-species status they underscore the uniqueness of both these moths and The Burren because the variations arise from the interaction of the moths’ genetic character with features of this exceptional environment.
All moth photographs copyright of Philip Strickland.