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The influences of biotic interactions on population biology of Sanguisorba officinalis
Větvičková, Anna ; Janovský, Zdeněk (advisor) ; Jičínská, Jana (referee)
Plants can interact with many different organisms on many trophic levels in their life. In this thesis I investigated how three biotic inertactions, powdery mildew infection, caused by Podosphaera ferruginea, predispersal seed predation by Dusky Large Blue (Phengaris nausithous) and Scarce Large Blue (P. teleius) and deer grazing affect life cycle and population biology of the Great Burnet (Sanguisorba officinalis L.). I also analysed their preferences of environmental conditions. Most of studied plant populations growth rates (λ) were lower than 1 and population decreased, but quite surprisingly for more populations vegetative reproduction was more important than reproduction by seeds. All intraction mentioned above affects more generative reproduction, and thus their influence on Great Burnet population dynamics is low, even with modelled maximal possible effect. Environment conditions analysis showed that powdery mildew occurs on sites with more flowering individuals, where spreading is very easy, butterflies preferred high, well noticeable flower heads grown high above other vegetation and host ant presence. For host ants' presence model locality was only significant variable.
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The status of Phengaris nausithous population on selected meadows in Broumovsko region
Štěpánková, Anežka ; Vrabec, Vladimír (advisor) ; Kamil, Kamil (referee)
The purpose of this thesis entitled Population Status checkered blue butterfly Phengaris nausithous (Bergsträsser, 1779) on selected meadows in Broumov area was to find and evaluate the situation regarding the size and structure of populations of the butterfly Phengaris nausithous, on a recently selected location within the territory of the Czech Republic. A used monitoring method was a Capture-Recapture method at 13 locations in the PLA Broumovsko, where the occurrence of the food plant Sanguisorba officinalis, which is an integral part of the species evolution, was the key for choosing the location. The ant of the genus Myrmica is also important for the evolution of the P. nausithous. The results were evaluated using the program MARK and Statistika and then transferred into graphs and tables. In 2016 it was marked 687 of the P. nausithous and the sum for the overall metapopulation totaled 1,487 individuals. Most of the P. nausithous occurence with the number of (fixed catches) 149 was registered at the Hynčice 2 (H2) area, which was the third largest area of all studied habitats. The least number of 15 of the P. nausithous has been marked at the Hynčice 1 (H1) area. Maximum estimates of numbersfor patches were determined with the program MARK with the highest number of 367 individuals in the H2 area, whereas the lowest number of 38 individuals at the H1 area.The numbers of P. nausithous determined by the application MARK were significantly higher than those of fixed catches, indicating good aplication of methodology. It was captured a total of 49 migrations. Overall 31 % of individuals migrated and 18 % of individuals migrated within assumed total number. Most flyovers were between the areas H2 and H4 (11 flyovers) and between areas V1 and H4 was recorded flyover at a distance of 5.3 km, which can be considered as one of the longest flyovers. The average distance of migration of P. nausithous was 1.46 km. The number of immigrants for solid flyovers was set to 49 individuals and the number of immigrants to 58 individuals. The hypothesis of this work was: All the examined areas communicates using flyovers of butterflies and the system can be considered as a single metapopulation and was confirmed given on the basis of the results. Target species dependence on the density of host plant vegetation was not crucial according to the graphic representation. The first T-test found that there is no association between P. nausithous abundance and between the length of the migration between particular areas. The second T-test found that with increasing number of flyovers the length of those flyovers gradually decreased.
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Influence of meadow management on the migration behavior of selected species of butterflies
Bubová, Terezie ; Langrová, Iva (advisor) ; Farkač, Jan (referee)
Migrations are the key process and one of the basic biological features, which allow survival of endangered species in fragmented landscape. In the last decades, agriculture intensification, industry and urbanization caused that number of natural butterfly habitats has significantly decreased. The localities originally suitable for butterflies are currnetly converted to farmland or building plots. This PhD thesis aimed to find a compromise solution of meadow management, which should allow a commercial use and concurrently do not jeopardize the continued existence of endangered or threatened species. The main idea of this study was in the intentional emigration causing in the middle of flight period, which should lead into resettlement of the population to another (potentially more suitable) locality. Possibility of aimed manipulation with butterfly emigrations would be considered as a major breakthrough in their protection.
The investigated species Phengaris nausithous (Bergsträsser, 1779) and Phengaris teleius (Bergsträsser, 1779) are both considered to be flagship species for protection of European butterflies at open meadows. This study is based on research, which was carried out in 2013-2015 at 17 patch in localities Dolní Labe, Czech Republic. In above mentioned years, one selected meadow was mowed in the middle of flight season and the emigrations were then monitored using mark-release-recapture method. Results of population and migration characteristics were calculated in MARK 8.1 software. Subsequently, the effect of mowing on emigration (comparison of emigrations from the meadow before and after mowing) was evaluated using Statistica 13.
The hypotheses of this study were based on the assumption, that the loss of resources after well-timed mowing should increase the activity of adult butterflies. During the monitoring, number of emigrations was increased only in flight season 2015. Unfortunately, the statistical evaluation did not show significant effect of mowing on migrations. On the other hand, the hypothesis dealing with colonization of nearest meadows was confirmed.
Effect of intentional emigration caused by management interventions was unfortunately not proved. However, we found out, that even though the population at one mowed meadow decreased clearly, the metapopulation size at the locality remained more or less stable.
At investigated (mowed) meadow, there was observed a sharp decline of P. nausithous abundance. On the other hand, P. teleius population was only slightly reduced. It is therefore conceivable, that P. teleius are not as susceptible to innapropriate term of mowing. The results obtained in our research conclusively displayed no possible positive effect of mowing in the middle of flight season and a necessity of suitable management maintenance at localities inhabited by Phengaris butterflies.
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