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The Grayling Hipparchia semele L. belongs to rapidly vanishing butterfly species in its central and western European range. We studied larval microhabitat preferences of two last viable populations of the Grayling in the Czech Republic. The field study was carried out at two types of human-influenced habitats: a fly ash deposit — a postindustrial site partly left under natural succession processes, and a semi-natural extensively grazed xeric calcareous grassland in May and June 2012 and 2013. During five nights, 89 caterpillars were found (fly ash deposit: 8, xeric grassland: 81). The caterpillars were found on steeper slopes covered with sparse shrubs and shorter herbaceous vegetation with high amount of bare soil or rocks. The most frequently observed behaviour was feeding on fine-leaf fescue grasses with varied size of tufts and rather smaller height up to 20 cm. Usage of larval preferences in a way of active conservation management application is discussed.
Post-industrial sites, including fly ash deposits, are common landscape components in many Central European regions. Their effective restoration is thus crucial because such habitats have been recognised as critical secondary refuges for many endangered and declining species. Controversially, the overwhelming majority of restoration projects consider vegetation units as the restoration target and thus ignore various habitat resources of many endangered species. Our study details habitat-use of the grayling Hipparchia semele, a European endemic xerothermophilous specialist and one of the most rapidly declining butterflies in Central Europe, inhabiting a fly ash deposit in the Kadaň region, western Czech Republic. We estimated its population to 510 males and 346 females by the capture-mark-recapture method during its whole flight period. By detailed recording of all observed specimens' behaviour, we show that this species uses resources from distinct vegetation units, such as exposed and disturbed spots, ruderal regrowths, solitary trees and shrubs, rocks and artificial concrete structures. Because the studied population can act as a source for the whole region, the grayling's ecological needs should be considered in any restoration project. Oppositely, the originally planned restoration of dry grasslands based on plant species composition of vegetation would very probably threaten one of the last two metapopulations in the whole country. Using the grayling's case, we thus warn against the vegetation-based habitat approach in restoration ecology; the resource-based habitat approach should be prioritised, especially when considering needs of the most threatened and/or umbrella species.
To test the hypothesis of random oviposition by Maculinea butterflies we investigated the oviposition patterns of M. alcon Denis & Schiffermüller in wet meadows in the Vistula valley, southern Poland, in relation to the stem length and flower number of Gentiana pneumonanthe Linnaeus foodplants as well as to their spatial distribution, the height of the surrounding vegetation and the presence of potential ant hosts. Analysis conducted for 403 gentians recorded within the 0.96 ha study plot indicated that plants with M. alcon eggs present were significantly higher and had more flowers. On the other hand, neither the local density of gentians nor the presence of ant hosts had any apparent effect on oviposition preferences of M. alcon. Our conclusion is that females of the butterfly select visually conspicuous plants as the oviposition sites regardless of their clumping or ant presence. As a consequence, the two factors do not need to be included in computer models developed to study the population dynamics of the species and its trophic interactions with foodplants and ant hosts.
The study was carried out in 1999–2000 in midfield shelterbelts located in mosaic agricultural landscape near village Turew (West Poland) with the aid of transect method (total length amounted to 4520 m). Five shelterbelts (transect length – 3070 m) have been planted in 1993 and one shelterbelt (transect length – 1450 m) in 1998. All the shelterbelts have been planted on arable land. Twenty seven species of butterflies (imagines) were recorded during the study period. Pieris napi and P.rapae dominated in all shelterbelts. Their dominance in 6–7 years old shelterbelts amounted to 30 and 24%, respectively, while in younger one (1–2 years old) – 34 and 32%. Total mean density of butterflies in older shelterbelts was equal to 91.9 ind. km⁻¹ of transect (width 5 m) – and was about 40% higher than in the younger one. Lower dominance of Aphantopus hyperantus (8%) observed in 6–7 years shelterbelts (when compared to several tens years ones) was most likely caused by small share of grasses and perennial dicotyledons, which are important for this species. The butterflies recorded in shelterbelts may be assigned to four ecological groups: ubiquistic species (7 spp.), species typical for open area (10 spp.), species linked to afforestations (3 spp.) and woodland (7 spp.). In all studied shelterbelts most abundant were ubiquistic species and open areas species (Pieris rapae and P. napi) with no respect to age of shelterbelt. Also some rare species with higher environmental demands were recorded, i.e., Polyommatus amandus and Carterocephalus palaeon, which have not been previously observed in the study area.
79 butterfly species have been recorded from the Roztocze National Park; localities are listed for all of them.
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