Wednesday 7 August 2019

Full immersion into Lepidopteras

Last week I (Sara) took part on a 6-day long camp for biology students (Biocamp), organised by the Association of Conservation Biologists from Koper. This year the camp took place in the Vipava valley and in the village of Čepovan near the Trnovo forest. This time I was given the leadership of the study group for butterflies. The wider area of the Vipava valley is known as one of the richest regions for butterflies in Slovenia. Our group visited different environments such as lowland wet meadows, dry meadows at the edge of the Trnovo plateau and various forest environments. In 6 days we visited 14 different locations and found 56 different species of butterflies. Below you'll find photos and descriptions of some of the most interesting species we found during the camp, as well as some pics that Domen took during two trips in the wider area of the Vipava valley, during the same week.

Wet meadows of Vipava valley
There are very few natural wet meadows left in the Vipava valley. These habitats were largely destroyed, dried up and converted into arable fields. The only two wet areas left in the valley are set in the vicinity of the village of Ajševica and in Mlake military area near Vipava. The latter was even recognised as a hotspot of butterfly diversity in Slovenia (see article).
Large Copper Lycaena dispar, south of the village of Potoče. The species is confined to humid grasslands but in this case it was found in quite intensive farmland on the only field of uncut vegetation. It seems that this provided sufficient habitat for the species.
Common Glider Neptis sappho, Ajševica. The species reaches the western edge of its distribution in the Vipava valley. The larvae feed on Black Pea Lathyrus niger, but also on the non-native and invasive Black Locust or False Acacia Robinia pseudoacacia. The very similar shape of the leaf of both species is presumably the reason of such a choice.
Scarce Large Blue Phengaris (Maculinea) teleius, Ajševica. The habitat of the species is characterised by the presence of the Great Burnet Sanguisorba officinalis - the larval feeding plant. A red listed and Natura 2000 species.
Gatekeeper Pyronia tithonus, Podnanos (Vipava).
Short-tailed Blue Everes argiades, Vipava valley.
Small Copper Lycaena phlaeas, Vipava valley.
Sooty Copper Lycaena tityrus, Vipava valley.
Oberthür's Grizzled Skipper Pyrgus armoricanus, Podnanos (Vipava).
Knapweed Fritillary Melitaea phoebe, Vipava valley.
Short-toed Eagle Circaetus gallicus (left) and Raven Corvus corax (right), Vipava valley.

Dry meadows of Trnovo forest's edge
The dry karstic meadows we visited are located at an elevation of about 1000 m a.s.l., on the edge of the Trnovo forest, rising above the Vipava valley. The area hosts a very rich flora, as well as a very high invertebrate diversity. Along the karstic ridge lies the boundary of different biogeographical regions where elements (species) from Continental, Mediterranean and even Alpine regions can be found. Up to 123 species of butterflies have been recorded in a 5x5 km square during previous censuses by keen Lepidopterologists. 
During our trips we could enjoy some of the typical species of mountain dry grasslands.
Meleager's Blue Meleageria daphnis, Mt. Kucelj. This was one of the most wanted species to see during the camp. It has a very fragmentated distribution in Slovenia and in the Karstic region its habitat is characterised by dry rocky terrain and steep dry grasslands.
Mountain Alcon Blue Phengaris alcon rebeli, Otlica. The end of July is a perfect time for the observation of Phengaris (ex Maculinea) blues. All 4 species of this genus found in Slovenia are red-listed. They have an extremely complex life cicle, as they are usually dependant on a very particular plant species and part of their development includes the parasitizing of ants.
Cross-leaved Gentian Gentiana cruciata, Otlica. The larval feeding plant of Mountain Alcon Blue, where the tiny white eggs can be sometimes found.
Great Sooty Satyr Satyrus ferula, southern edge of Trnovski gozd.
Dryad Minois dryas, Vipava valley.
Owlfly Libelloides macaronius, Nanos plateau.
Carniolan Burnet Zygaena carniolica, southern edge of Trnovski gozd.
Holly Blue Celastrina argiolus, southern edge of Trnovski gozd.
Common Swallowtail Papilio machaon, southern edge of Trnovski gozd.
Solitary wasp sp. Scolia hirta, southern edge of Trnovski gozd. A rather large parasitic wasp, typical of Mediterranean regions that lays its eggs in the larvae of Rose Chafers (Cetoniidae).
Three-veined Hare's-ear Bupleurum ranunculoides, Nanos plateau.
Common Houseleek Sempervivum tectorum, southern edge of Trnovski gozd.

Forest environments
Even if the forest environment is usually less productive in the terms of butterfly diversity, we still managed to encounter some interesting species. In the mountain forests of Trnovski gozd the highlights were a magnificent (and very cooperative) Purple Emperor Apatura iris and a White Admiral Limenitis camilla. Several ringlets were also found, including the localised Styrian Ringlet Erebia stirius, Arran Brown Erebia ligea and Scotch Argus Erebia aethiops. A common woodland species was Woodland Grayling Hipparchia fagi.
Purple Emperor Apatura iris, Trnovo forest.
Woodland Grayling Hipparchia fagi, Trnovo forest.

Earlier this week, even after the end of the summer camp, we were again in the field looking for butterflies. While passing through Ljubljana we made a short session in the wet meadows of Ljubljansko barje, where we found some interesting species including Map Butterfly Araschnia levana, several Large Coppers Lycaena dispar, as well as an interesting longhorn beetle: the Musk Beetle Aromia moschata. However we were unsuccessful in our quest to find the localised Small Pearl-bordered Fritillary Clossiana selene, which at Ljubljansko barje has an isolated population. Next time lucky...
Map Butterfly Araschnia levana, Ljubljansko barje.
Musk Beetle Aromia moschata, Ljubljansko barje.
Mouse Garlic Allium angulosum, Ljubljansko barje.

Meanwhile in the Karst close to home the Amethyst Eryngo Eryngium amethystinum is in bloom all over the limestone grasslands and is attracting good numbers of butterflies, like the typical late-summer False Grayling Arethusana arethusa.
False Grayling Arethusana arethusa, Karst.
Red-underwing Skipper Spialia sertorius, Karst.
Small Heath Coenonympha pamphilus, Karst.
Honey Buzzard Pernis apivorus, Karst.