Martin Kulma

Land management impacts on European butterflies of conservation concern: a review

Recent land use changes, namely the intensification of agriculture and forestry as well as the abandonment of traditional grassland management methods, have resulted in the decline of butterfly diversity in Europe. Appropriate management of butterfly habitats is thus required in order to reverse this negative trend. The aim of our study was to review the available literary information concerning the effects of various types of management on European butterflies of conservation concern, and to provide practical recommendations for the management of butterfly habitats. Since vegetation succession is a major threat to butterfly populations, there is a need for activities to suppress this process. Extensive grazing and rotational mowing, which imitate the traditional way of meadow use, appear to be the most suitable management in this respect. Both grazing and mowing should optimally be of low intensity and follow a mosaic design, with different land fragments being successively used at different times. Habitat disturbance through trampling, either associated with grazing or various sporting activities (hiking, biking, horse riding), or through occasional small-area burning, also prove to be beneficial for many butterflies. In the case of woodland species, maintaining open habitats within forests (glades, clearings, wide road verges) and thinning forest stands is recommended. Among the unfavourable management activities identified, the most harmful are afforestation of open lands and drainage works. Therefore, such activities must be stopped at butterfly sites in order to ensure the effective conservation of species of conservation concern.

Adult longevity and its relationship with conservation status in European butterflies

Many European butterfly species are currently experiencing serious declines, and may be threatened with extinction. Nevertheless, due to limited knowledge on the species biology and ecology, detailed assessments of endangerment level are not possible, and instead identifying species of conservation concern has to rely on proxies. Earlier studies suggested several characteristics, including host plant specificity, overwintering stage, patch size requirements or mobility, as potentially useful indicators of butterfly species vulnerability, but the usefulness of adult longevity in this respect has not been considered so far. Based on the information gathered through an extensive literature search we investigated the relationship between adult life span, flight period length or the temporal fragmentation index calculated as the ratio of the two parameters, and conservation status of European butterflies. We found that the species classified in one of the IUCN conservation concern categories (i.e. Endangered, Near Threatened, or Vulnerable) lived shorter as adults and were characterised by higher values of the temporal fragmentation index, while there was no particular pattern concerning flight period length. We believe that the apparent effects detected reflect the fact that shorter adult life span, and thus increased temporal fragmentation, in combination with protandry, i.e. earlier emergence of males, decrease individual chances of finding mating partners. Such a situation leads to lower effective population size and reduced viability, especially in the case of small populations. All concerned, the investigated parameters reflecting adult longevity may serve as ‘early warning’ indicators, helping to flag-up butterfly species possibly at risk.

Long-term monitoring of Phengaris (Lepidoptera: Lycaenidae) butterflies in the Přelouč surroundings (Czech Republic): is the waterway construction a serious threat?

The monitoring of sympatrically occurring Phengaris teleius and P. nausithous metapopulations in the surroundings of Přelouč, Czech Republic, was launched over a decade ago in connection with the planned waterway construction on the Elbe river. The mark-recapture surveys were initially restricted to 10 habitat patches on the right river bank, but in 2010 three new patches were discovered on the opposite bank. We use the monitoring results for 2011–2015 to assess how the discovery of additional populations alters the impact evaluation of the prospective construction. The overall abundance of P. teleius in the recently discovered populations was about twice as high as on the right bank (ca. 2,800 vs. 1,400 adults on average), while the numbers of P. nausithous on both banks proved to be balanced (at ca. 600 adults on average). Furthermore, we confirmed a substantial exchange of butterflies between population representing both banks, which indicates a well-integrated metapopulation in both species. Since the waterway would partly destroy the two largest populations on the right bank, the potential loss due to its construction is estimated at 40.1–64.3% P. teleius individuals and 20.2–47.4% P. nausithous individuals occurring there. Nevertheless, concerning the entire metapopulation, the predicted decline is considerably smaller, reaching 13.9–25.7% in P. teleius and 8.5–20.0% in P. nausithous. Consequently, a long-term survival of the species is likely even in the case of the waterway construction, as long as appropriate management is applied on the unaffected habitat patches.

Effect of sex on the nutritional value of house cricket, Acheta domestica L.

Since January 2018, insects have been recognised as novel foods in the EU, but their nutritional value varies, and factors affecting their nutritional composition have been debated. We investigated the effect of sex on the nutritional value and chemical composition of the house cricket (Acheta domestica L.). Both sexes were rich in protein and lipids. The proximate composition was partly influenced by sex; females contained a significantly higher amount of lipids (18.3-21.7 vs 12.9-16.1 g/100 g dry matter, p = 0.0001) and fewer proteins than males (61.2-64.9 vs 66.3-69.6 g/100 g dry matter, p = 0.0001). Males contained more chitin (p = 0.0015) and nitrogen chains (p = 0.0003) than females. Only the ash (p = 0.4314) and nitrogen-free extract (p = 0.4871) were uninfluenced by sex. Furthermore, nutrient quality expressed as essential amino acid (72.3-77.1), thrombogenicity (1.22-1.45), and atherogenicity indices (0.53-0.58) did not differ between sexes (p > 0.05).

Intensive Mowing Effect of One Patch on the Metapopulations of Two Phengaris Species

Abstract In the second half of the 20th century, change of land use in the name of intensive agriculture was one of the most important factors caused significant loss of butterfly diversity in Europe. Phengaris nausithous and Phengaris teleius belong among the flagship species associated with wet meadows and are directly threatened by the intensive agriculture practises or management abandonment. Due to their very specific lifecycle, they are closely linked to their habitats and appropriate mowing management on their patches is thus crucial for their survival. Our research took place in Dolní Labe, Děčín, Czech Republic, on 16 patches and has been performed using Mark-Release-Recapture since 2009. This paper will illustrate how intensive mowing management, applied on only one of the patches, which forms only 9.4% of total locality size, can influence the entire local Phengaris metapopulation. The selected patch was intentionally mowed in the middle of flight season annually for four years. Even though, no significant effect was identified after the first year of study, after the second and third seasons, there was evidence of population decline of both studied species.

Lavender, Eucalyptus, and Orange Essential Oils as Repellents Against Ixodes Ricinus Females

Abstract This study evaluated the repellent effect of three essential oils against females of Ixodes ricinus, which is considered to be the main arthropod disease vector in Europe. The essential oils could be regarded as user- and environment-friendly alternatives to synthetic repellents. As a comparison sample, the most widely used synthetic repellent DEET was used. All the tested oils exhibited moderate to high initial repellency of 65-85% 5 min after application. The testing was terminated after 80 min, when lavender and eucalyptus repelled 45% and 15% of ticks, respectively. No effect of orange oil was observed after a 20-min mark. The effect of DEET was found to be high and stable (95-100%) throughout the experiment. This study thus revealed that the investigated oils are not as effective as DEET. On the other hand, especially lavender showed an interesting potential as an alternative repellent for outdoor activities of shorter duration.

Evaluation of Active Management Applied to Meadows with Phengaris Butterflies Occurrence

Abstract In recent decades, changes in meadows maintenance have reduced the populations of endangered butterfly species Phengaris nausithous (Bergsträsser, 1779) and P. teleius (Bergsträsser, 1779). Currently, meadows are either abandoned or intensively used. Unfortunately, both these managements are considered unfavourable for grassland butterfly species. In this study, the effect of suitable meadow management on population sizes of both the above mentioned Phengaris species was investigated. The experiment was performed at the locality Dolní Labe (Děčín, Czech Republic). The most suitable models, based on the lowest values of Akaike’s information criterion corrected for small sample sizes, were selected using MARK statistical software. The results were subsequently compared with data obtained from this locality prior to the management application. Unexpectedly, no significant positive effects were found. To reach the desirable status, suitable management practices should be applied for long-term. To verify the management effect on the population size, the meadows were divided into three groups: (i) application of favourable management, (ii) mowing in inappropriate term, (iii) without management. Based on the statistical evaluation, the management application proved to be the most favourable option for both studied butterflies species.