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Abundance and habitat use of reintroduced populations of the Hermit (Chazara briseis) in the Czech Republic
Pešová, Lucie ; Sedláček, Ondřej (advisor) ; Vrba, Pavel (referee)
The Hermit (Chazara briseis) belongs to the critically endangered species in the Czech Republic. Its last population survived until recently in the NPR Raná in the České středohoří Protected Landscape Area, but it has gradually declined. The specie's habitat is short-stemmed grasslands, which are maintained mainly by extensive grazing and management. Currently, these sites are declining, traditional management has changed and the sites are gradually becoming overgrown. Therefore, the reconstruction of the butterfly's habitats has been undertaken in selected localities that the butterfly used to inhabit in the past, in the České středohoří Protected Landscape Area (PR Číčov, Dlouhá hora, PP Radobýl) and in the Český kras Protected Landscape Area (Třesina, Radotín). Reintroduction of eggs and caterpillars took place in these sites in 2020-2021. The aim of the thesis was to evaluate the population abundance and habitat use of the Chazara briseis at these sites immediately after reintroduction. I estimated the size of the populations using the mark-capture-recapture method in 2020 and 2021. The size of the populations in the Lonské středohoří (Dlouhá hora and Číčov) was around 400-500 individuals with a fairly balanced sex ratio. Overflights were also recorded between these sites, which may indicate...
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Conservation of populations on the edge of geographical distribution
Pešová, Lucie ; Sedláček, Ondřej (advisor) ; Šípek, Petr (referee)
Populations on the edge of the range are often considered less valuable for conservation with regard to core populations of the species. These populations are often small, isolated and less genetically variable, and are therefore more prone to extinction. On the other hand, there are some studies claiming that some peripheral populations could have genetically unique allels which could help them adapt to changing environmental conditions. They thus have a big speciation potential. Peripheral populations could also occur behind state borders, where the species has conservation status, despite the fact that it is a common species somewhere else in its range. Due to this contradiction, peripheral populations are a delicate topic of discussion in the scientific community. In this paper I summarized the features of populations on the edge and also factors which limit them. Furthermore, population dynamics of these populations and summary of the main genetic processes taking place in small populations are outlined here. Next there are arguments for and against conservation of populations on the edge. In conclusion I give model examples of species on the periphery, demonstrating their features and reasons for their possible conservation. Key words: population, conservation, peripheral, marginal, range...
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