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.