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Hodnocení vývoje ichtyofauny v dlouhodobě sledovaných úsecích pstruhových revírů jižních Čech
HALÁČEK, Josef
The work provides information regarding the current development of fish populations in 30 profiles located in 16 trout fishing grounds in South Bohemia, including possible connections with the method of fishing management, temperature, and flow conditions. The work also includes recommendations regarding changes in approaches to fishery management. It is recommended to open the question of the possibility of effectively regulating fish-eating predators as soon as possible. However, these recommendations can generally be applied to similar trout fishing grounds.
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Posouzení možnosti reintrodukce lipana podhorního vysazením uměle odchovaných generačních ryb v předvýtěrovém období
PASTEJŘÍK, Jan
My bachelor s thesis deals with the possibility of reintroduction of the European grayling (Thymallus thymallus) into open waters by stocking artificially bred generation fish in their pre-spawning period. 3-4-year-old broodfish, bred in the pond Hulák in Prachatice, were used for the experiment. Then in the spring the fish were marked and stocked in the parts of FROV JU fishing ground, where fish were previously caught with electric aggregates and the local composition of fish stocks was examined. In the same way, a control catch was carried out also in the autumn - this time there was a main focus on the presence of the European grayling and juveniles. In addition, a follow-up section of the river (outside the experimental sections) was fished out and most fish were caught here. Based on the results of the monitoring, it can be said that in the section of the river where artificially bred generation fish were stocked at least partially successful natural spawning took place. Although the number of caught fish in the autumn was low (11 fish), this approach might be considered as promising in terms of the possibility of supporting the occurrence of the European grayling in open waters and suitable for further testing. Only 6 % of stocked generation fish were caught out 7 months after stocking. The size of these fish was practically the same as when stocked. In case of using this approach within the fishery management, it is necessary to stock generation fish no more than a few weeks before the expected spawning.
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Hodnocení efektivity reintrodukce lipana podhorního (Thymallus thymallus L.) do vybraných lokalit jihočeských toků
KOLAŘÍK, Tomáš
The aim of this bachelor thesis is to evaluate the stocking efficiency and fishing records of European grayling in selected angling districts of South Bohemian Rivers based on the angling union data. Furthermore, additional aim is to evaluate the recent results of restoration/ enhancement of European grayling populations by stocking effort in sections of the Blanice Vodňanská River under the Husinec Reservoir and the Vltava River under the Lipno Reservoir. The European grayling was in the past abundant in both sections under study and natural reproduction was also recorded. However, this species almost disappeared in the recent years and its presence in these sites is rare these days.
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Zhodnocení rybářského managementu pstruhového revíru Svitava 5
Polívka, Lukáš
The main aim of this thesis is to evaluate the biological status of species populations of agriculturally important fish species in the district Svitava 5 and the evaluation of the evidence in the district's ten-year series. Ichthyological surveys were carried out in autumn 2015, on 20th and 21st November. At various locations were determined basic physicochemical parameters of the water and found topographical data. Catches were made by using electrical units. All fish were returned gently back to the territory after finding plastic signs. In all localities have been detected 3 fish species from two families. The total abundance ranged from 899 to 3634 ks.ha-1 and the biomass from 58.7 to 250.6 kg per ha -1. Big drop in the number of caught individuals was recorded at grayling, when it reduce the number of catches from 21 ks.ha -1 to 1 ks.ha -1 in the ten-year series.
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Comparison of ichtyofauna in morphologically similar parts of trout zone of two rivers with different kind of management
ČEJKA, Jakub
The topic of this bachelor´s paper is comparison of biodiversity of fish community in morphologically similar parts of two South Bohemian rivers the Malše and the Blanice, which vary in the kind of fish management. There were chosen four parts of both rivers in the trout to the grayling zone, which were fished with a power generator in spring and autumn 2015. Fished fish, which are important for the fish management, were measured and weighed individually and then all the fish were given back to the parts. Gained data were processed. The parts, which were compared, are CHRO (freshwater fish protected areas), areas, where only original species are handled (brown trout (Salmo trutta m. fario, Linnaeus, 1758) and european grayling (Thymallus thymallus, Linnaeus, 1758)) and areas, where apart of original species rainbow trout popular with sport fishermen (Oncorhynchus mykiss, Walbaum, 1792) is handled. A similar trend of higher stability and condition of original species population in higher located parts of monitored fish district of both rivers was found out. There is a probable dependence of brown trout´s and grayling´s presence on handling of fries, which are heavily influenced by the presence of unoriginal species and sport fishing in the lower parts of the Malše river. It is possible to assume the existence of natural reproduction and subsequent sustainability of both species populations in the above-lying areas. The population of brown trout in the Blanice river can be judged like sustainable by itself in all the parts and influenced by undesirable fish species only in the lower parts. The presence of grayling in all the parts is probably dependent on fish migration from the lower part of the district and there is grayling only sporadic in the higher located parts.
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Zhodnocení rybářského managementu pstruhového revíru Svitava 4
Mareš, Lukáš
Presented master thesis deals with the issue of assessment of management in salmonid fishing ground Svitava 4. The main aim was to compare the state of fish community with the state after the last survey from 2003-2004 and to evaluate the economic evidence (level of fishermen's pressure, level of reached catch and the stocking of economically important species) for ten years in a row. The ichthyological survey was carried out in summer season in 2014 at four localities within the fishing ground Svitava 4. The topographic data of particular localities were measured by the modern devices. Also basic physicochemical parameters of water were measured. The catching was realized by electric-fishing gear. After measuring of morphometric characteristics all the fish were returned back to the fishing ground. The survey established the presence of 8 fish species in 5 families. The abundance of fish community varied on particular localities in the range from 338 to 1633 pcs.ha-1, the biomass from 53,6 to 199,2 kg.ha-1. The fish community of concerned stream has gone through significant changes since the last survey. Considerable decrease in abundance was recorded mainly in the grayling population.
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Zhodnocení trendu vývoje úlovků lososovitých ryb a lipana podhorního ve vybraných pstruhových revírech řeky Svitavy
Polívka, Lukáš
Bachelor's work is targeted on factors affecting number of fish society on trout fishing areas, mainly of salmonids and grayling. Further more work is targeted on evaluation of anual catches of fish listed below on trout areas Svitava 3,4 and 5 in last 15 years. This results will be compared to fishing pressure on monitored areas with level of releasing of fis listed below. For evaluation of catches, fishing pressure and level of released fish was used evidence of trout kinds fish areas MRS in Brno. Results are showing, that the largem number of catches in last 15 years are in Svitava 3 area, which i also under the biggest fishing pressure. On the contrary the most fish released were in area Svitava 5. Enviromental factors in Svitava river are distictly better than in 1989. In this improvement are involved many closes of troubled facilities and also wastewater treatment plant.
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Zhodnocení rybářského managementu pstruhového revíru Svitava 2
Bromek, Petr
The main aim of the diploma thesis is to evaluate the fish management of a trout reserve Svitava 2 and to suggest a correction on the basis of results from the performed surveys and information from the Moravian Fisherman's associotion evidence. Field surveys were realized on 3rd and 4th September 2013. During these surveys 12 fish species out of 5 families were demonstrated by electrofishing. Caught fis were released back to the river measuring weight and lenght. The ichthyologic research was evaulated using indi-cators for fish populations. On account of acquired knowledge and data, I recommend following correction: advance quantity biennial brown trout on 200 fish per hectare, reduce rainbow trout 40 fish per hectare and advence quantity biennial qrayling on 200 fish per hectare.
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