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Fish stock survey of Lake Piburg in 2023
Holubová, Michaela ; Draštík, Vladislav ; Peterka, Jiří
The report was prepared based on the results of complex survey of the fish stock of Lake Piburg in 2023. The aim of the ichthyological survey was to map the state of the fish populations in Lake Piburg, especially with an emphasis on estimating the abundance and biomass of individual fish species and recommending further management of the fish stock. A summary of the achieved results and a proposal for improvement of water quality via management of fish populations are included in the report.
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Ellimination of unwanted fish species from dam reservoirs - Possibilities, efficiency and economic evaluation.
Jůza, Tomáš ; Blabolil, Petr ; Čech, Martin ; Draštík, Vladislav ; Holubová, Michaela ; Hůda, J. ; Kočvara, Luboš ; Kolařík, Tomáš ; Muška, Milan ; Peterka, Jiří ; Prchalová, Marie ; Říha, Milan ; Sajdlová, Zuzana ; Tušer, Michal ; Vašek, Mojmír ; Vejřík, Lukáš ; Kubečka, Jan
spontaneous development of populations and the influence of human interventions. For situations where a certain part of the fish population needs to be caught, within the project 'Biomanipulation as a tool for improving the water quality of reservoirs', we tested the available approaches in terms of their effectiveness and difficulty. The target species of catches were mainly cyprinid fish (bream, bleak, roach, rudd, white bream), which feed mainly\non zooplankton and tend to form very large populations. Among the most effective methods of catch during spawning are catches using electrofishing boats and fyke nets. In the non-spawning period, it is possible to carry out mass catches using trawl nets. Catches are effective both before spawning (in April) and during the summer. However, with repeated catches in the same places, their effectiveness decreases as a result of the fish being spooked. The efficiency of the catches partially improves again if the catches are repeated with a break of approximately 1–2 weeks. Catches also vary according to the stocking density of a given water body. With effective catches, the cost of catching 1 kg of fish is in the range of CZK 15–50.
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Druhově specifické hejnové chování ryb ve sladkovodní nádrži.
HOLUBOVÁ, Michaela
This study handles the problematics of schooling behaviour in the pelagic habitat of a temperate freshwater reservoir by the means of underwater visual survey via underwater camera. UVC proved to be a great tool for obtaining behavioural patterns which are rather poorly studied in the pelagic zone. Four species were identified as school forming. Naturally, schooling tendency varied in between species mostly due to proneness to predation, increasing with vulnerability to a predator. Heterospecific schools were quite common, particularly in vulnerable species sharing a space and food niche with species less attractive to predators.
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Pozorování hejnového chování ryb v pelagickém habitatu umělé vodní nádrže prostřednictvím videokamery
HOLUBOVÁ, Michaela
The research presented in this thesis contributes to broadening of the knowledge on free-living adult fish schools and behavioural patterns in a temperate freshwater reservoir. The behaviour of fish in the pelagic zone is rather poorly studied. Naturally, schooling tendency varied between species mostly due to increasing vulnerability to predation. Heterospecificity in schools was not a rare phenomenon, mainly for vulnerable species that shared the same space and food niche with a predatory less attractive species. The individual needs fluctuate as factors might be reconsidered in short time periods and most probably are reflected in behavioural responses. Individual responses are also reflected in the distribution of the fish in the reservoir and density in particular habitat. There is a "critical density" that triggers the formation of fish schools, followed by a slowing increase in density of fish clusters (observed units). This corresponds to increasing proportion of fish in a school and declining proportion of singletons. The trend of count of clusters tended to have an upper limit that should result in constant count of fish clusters after reaching a particular fish density. In other words, fish in the habitat maintain maximal distances even when the density increases. During high density periods the distances are kept by school formation. Overall the usage of the visual census as presented, proved to be a convenient tool for observation and assessment of freshwater fish. It has been demonstrated that the method can obtain comparable results to hydroacoustic survey amounts as well as purse seining.
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Results of the autumn extended research of the ichthyofauna of the lakes Laka and Čertovo, including the adjacent streams.
Blabolil, Petr ; Bartoň, Daniel ; Draštík, Vladislav ; Jůza, Tomáš ; Hladík, Milan ; Holubová, Michaela ; Hůda, J. ; Kočvara, Luboš ; Muška, Milan ; Peterka, Jiří ; Vrba, Jaroslav
The report describes the results of a unique survey of the ichthyofauna in two areas of the Šumava National Park, where catches were made by an electric generator in the autumn of 2021.
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The influence of balance aids to better quality of handwriting of chidren with ADHD
Holubová, Michaela ; Kobesová, Alena (advisor) ; Štveráková, Tereza (referee)
The children from all over the world suffer from ADHD (Attention Deficit Hyperactivity Disorder) and this disorder is a great social, educational and medical problem at schools. This bachelor thesis focuses on the etiopathogenesis, symptoms, diagnosis and treatment. The pharmacological treatment is not the only way which effectively helps children with their problems at school and in personal life. Exercise and regular physical activity is very important for children and it can impact on symptoms of ADHD. The experimental section of this bachelor thesis deals with the influence of balance aids to handwriting of children with ADHD. The thesis compares their handwriting before and after three months, during which the children were using the aids for the dynamic sitting. The experimental section includes four casuistics of children with ADHD, the results of standardized test MABC-2 for the evaluation of children's fine and gross motor skills and balance and a detailed analysis of writing from the point of view of specific features. The effect of therapy was evaluated using the total score which was recalculated to percentiles in the test MABC-2, handwriting was evaluated using specific features in the script. The therapy revealed itself as effective. Keywords ADHD, test MABC-2, sensory processing,...
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