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Changes in distributional range and ecology of bats realated to climate change
Pavlíková, Barbara ; Lučan, Radek (advisor) ; Bartonička, Tomáš (referee)
In the last few decades bats are affected by climate change. Changes in average temperatures affect their morphology, phenology, diversity and distribution. Changes in biotopes caused by anthropogenic influences are responsible for the loss of shelters and connectivity of habitats. Empirical data show us that the range expansion of many bat species are gradually shifting to higher latitudes or altitudes. Mathematical models predict that the bat diversity and richness around the world will decline. Some species will shift their ranges and some will shrink their range or even become extinct. Key words: chiroptera, bats, range shift, bioindicators, climate change
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Genus Neomys (Mammalia, Eulipotyphla, Soricomorpha): history and range dynamics.
Pažitková, Barbora ; Horáček, Ivan (advisor) ; Vohralík, Vladimír (referee)
Based on numerous literary sources, the thesis reviews current knowledge of history and range dynamics of the genus Neomys, an indexing element of the west Palearctic mammal fauna. It provides a list of fossil records attributed to the extant genus Neomys and extinct clades composing the European records of tribe Nectogalini, and a survey of hypotheses on their phylogenetic relations. Particular attention is given to the genus Asoriculus which is generally considered as an ancestor of the Quaternary radiation of the clade represented in Europe with genera Nesiotites, Neomys and Macroneomys. The transition from Asoriculus to Neomys is expected to appear during the Q1 stage of the Early Pleistocene, more records identified as fossil species of the latter genus are reported from terminal stage of the Early Pleistocene (Q2). Nevertheless, their relations to extant species were not analysed and past history of the extant European taxa (fodiens, anomalus, milleri) and their range dynamics is despite of molecular data generally unclear. This fact reflects both scarcity of the fossil record and uncertainties regarding patterns of phenotype variation in particular species, their discrimination criteria and orientation of corresponding phylogenetic morphoclines. In these regards, the thesis pays special...
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Abundance trends and range dynamics in European bats.
Žabková, Klára ; Horáček, Ivan (advisor) ; Lučan, Radek (referee)
Bachelor thesis sumarizes available data about bat abundance in middle Europe, especially in the Czech republic. Populations of bats are usually dynamic, which is given by their high sensitivity to environmental changes. Many of these changes are man made, for instance landscape management, agricultural intensification or disturbing bats during hibernation. Impact of global warming on bat abundance and range distribution is also discussed, because it could explain the occurance of mediterranean species Hypsugo savii in Moravia In my thesis, I focus on possible causes of strong population decrease of Rhinolophus hipposideros in 70's in the middle Europe, which led to establishement of monitoring programms accross Europe. Project "Monitoring bats in underground hibernacula" has started in Czechoslovakia in 1969, and it has provided valuable and relevant data. I also compare methods for monitoring bats, because there isn't any effective universal method for censusing all species under all circumstances, due to their specific behavioral habits. Counting bats in underground hibernacula appears to be the most efficient, especially for species such as Rhinolophus hipposideros, Myotis myotis and Plecotus spp. Statistic methods are used to estimate colony size, Lincoln-Peterson method seems to be the most suitable...
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