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Molecular demography of brown bear in the Western Carpathians
Tkáčová, Nikola ; Hulva, Pavel (advisor) ; Tkadlec, Emil (referee)
Reliable estimates of population size are an essential tool for effective species conservation and management. The aim of this master thesis was to estimate the census population size and describe genetic variability and structure of the brown bear (Ursus arctos) using non-invasive genetics in Slovakia, which includes the majority of the West Carpathian population. A total of 2,172 samples were obtained during 2019-2021. The majority of the samples were non-invasive, mainly stool samples, which were complemented with tissue samples from roadkills or legally culled animals. Subsequently, DNA was purified and 12 microsatellite loci and the SRY sex marker were amplified. 1036 genotypes were successfully determined, of which 632 were unique. The Slovak population of bears posses a relatively high genetic diversity and similar values of heterozygosity as populations in areas with good state of conservation and relatively intact landscape. Based on Bayesian clustering analysis, population was divided into four clusters, with a certain level of gene flow. Only one cluster was detected in the eastern part of Slovakia (Eastern Carpathians). In the central part of Slovakia (Western Carpathians) all clusters were represented. Observed male to female ratio was 1.006. In males, a higher recapture rate was...
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Distribution of predators, predation risk and antipredation strategies in waterfowl
Kreisinger, Jakub ; Albrecht, Tomáš (advisor) ; Bureš, Stanislav (referee) ; Tkadlec, Emil (referee)
Jakub Kreisinger - summary of the Ph.D. thesis: Predation is an important selective force affecting many evolutionary and ecological process. Anthropogenic landscape changes often alter these processes due to qualitative and quantitative changes in the predator comunity. This thesis contains four papers that are focused on various aspects of the nest predation, antipredation strategies and distribution of predators in the landscape modified by human activities. The first contribution "Nest protection in mallards (Anas plathyrhynchos): Untangling the role of crypsis and parental behaviour" (Kreisinger & Albrecht 2008) focus on the effect of antipredation strategies on the reproductive success in a ground nesting bird, mallard. Our data are consistent with the hypothesis that multiple antipredation strategies including nest site selection parental antipredation behavior and crypsis due to clutch concealment by the nest material during incubation recesses reduce sumultaniousely the risk of the clutch predation in birds. Contrary to some previous studies, the relative effects of crypsis and parental anti-predation behaviour on nest survival did not differ with respect to antipredation effect of the nest concealment by surrounding vegetation. The hypothesis that linear strips of shrubby vegetation and high grass...
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Strategie mateřské investice u modelového monotokního a polytokního savce z pohledu životní historie
Dušek, Adam ; Stopka, Pavel (advisor) ; Šumbera, Radim (referee) ; Tkadlec, Emil (referee)
The litter size is one of the most important determinants of mammalian life-histories. Depending on the size of the litter, the mammals can be divided into two main groups: (1) the monotocous mammals, producing only one offspring per litter; and (2) the polytocous mammals, producing more than one offspring per litter. This life-history dichotomy entails different strategies whereby the mammalian females may optimize their maternal investment. The aim of this Ph.D. thesis is to show variation in the maternal investment strategies of monotocous and polytocous mammals from a life-history perspective. In order to address this issue, I investigated the strategy of maternal investment in the red deer (Cervus elaphus), representing a typical monotocous mammal, and the house mouse (Mus musculus), representing a typical polytocous mammal. From a life-history perspective, the red deer, producing no more than one litter per year, can be viewed as a model of "K-selected species", while the house mouse, producing up to ten litters per year, can be viewed as a model of "r- selected species". The red deer and the house mouse are ideal model organisms for this type of research also because they both are representatives of the most common mammalian mating system - the simultaneous polygyny. A general assumption of...
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