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Vliv hlaváče černoústého (Neogobius melanostomus) na potravní řetězec řeky Ploučnice
STANĚK, Pavel
Biological invasions are prominent factor affecting changes in invaded ecosystems. Invasive species can alter in food web of the indigenous community, which leads to changes in the community through ecological and economic effects. This work was focused on the effect of the Round goby (Neogobius melanostomus, Pallas 1814) food web of river Ploučnice. Round goby was first recorded recently in the Czech Republic (2015). Thus, it can still be considered a young invader into Czech inland waters. The main goals of this thesis were: I) to reveal Round goby food source preferences, II) to Competition between Round goby and European bullhead (Cottus gobio, L 1758), as this species is a native endangered species present at this locality. III) Possible preferences of Round goby as a putative food source of predatory fishes in sampled localities. For this purpose, River Ploučnice has been chosen. River Ploučnice flows into Elbe River, which is fully invaded by Round goby. Thus, the bottom part of the Ploučnice River is invaded by Round goby as well. However, thanks to the presence of migratory barriers between localities, Round goby has not yet been detected in localities upstream. To reveal mention goals all biota units in all localities were sampled. Later, stable isotope analysis (carbon and nitrogen) followed by Bayesian models were employed. In general, results suggest that this species had the highest abundance among other species in localities with an established Round goby population. In addition, results reveal Round goby as a true generalist regarding food source preferences. Comparing trophic niche width and overlap showed a significant overlap between some of the ontogenetic groups of round goby and European bullhead, reaching up to 67,8 %. Also, increased niche overlap between ontogenetic stages of European bullhead was observed when Round goby was present, in comparison to localities without the presence of Round goby. Additionally, predatory fish food preferences showed no specialization on round goby as a food source, although round goby was part of their diets. In conclusion, this was found round gobyas a consumer, competitor, and even as a food source for predatory fishes.
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Problematika invazních druhů raků na území České republiky
Čuprová, Veronika
The diploma thesis following the bachelor thesis "Invasive species in the Czech Republic" is focused on the issue of invasive species of crayfish. The aim of the thesis is to describe the legislation, the current method of monitoring these species and the possibilities of their regulation. The thesis deals with the monitoring of invasive crayfish species at two selected sites in the Czech Republic and the application of appropriate regulatory interventions. Along with the monitoring, water samples were taken and analyses for the presence of crayfish plague were carried out. The results show that at the Prostřední rybník site, where the marbled crayfish occurs and where eradication measures have been underway since 2020, it has still not been completely successfully eradicated. From the interview conducted with local respondents, it was found that about half of the respondents are aware of this issue, thanks to the actions carried out to eliminate this species and the information boards posted in the area. In addition to the signal crayfish, a small population of the native endangered river crayfish is also present at Besének. Regulatory measures have also been implemented at this site in order to eliminate this invasive species as much as possible and to prevent potential threats to the native crayfish. Based on the results obtained, further possible control measures were proposed at both sites. In the future, more focus should be placed on education of this highly topical issue, as public awareness and understanding is considered one of the most effective preventive measures.
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Aktivita raka signálního v podmínkách malého toku
DAVID, Jaroslav
The signal crayfish is one of the oldest invasive crayfish species in Europe, causing ecological and often economic damage in newly invaded locations. The invasion and associated problems can be monitored in real-time on the Křesanovský brook, where regular eradication measures have been carried out for six years. However, the detailed and comprehensive impact of these activities on the crayfish population as a whole and any changes in individual behaviour have not yet been studied in detail. To obtain relevant data for this purpose, this thesis video-recorded the situation in the stream in monthly cycles from May to September 2021, with recordings taken the night before and the night after thorough manual crayfish catching in the brook, evaluating the number and activity of observed crayfish. The results did not show that the trapping had changed the overall crayfish activity. Even with a high number of captured crayfish, the weakened crayfish population after trapping showed the same overall activity as the complete population before trapping (presumably due to an increase in individual activity in response to catching and accompanied habitat disturbance). Furthermore, the results underline the previously assumed low success rate of eradication efforts at the site and confirm that barriers in the stream are not sufficient to stop the signal crayfish spread. These findings will help to better understand the impact of eradication measures on signal crayfish populations. As this was the first research of its kind, this thesis opens up opportunities for methodological improvements and further development, as well as posing many new questions that need to be addressed. The ultimate goal of these efforts is to improve management interventions against invasive signal crayfish.
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Invasive pest species in fruit crops in the Czech Republic
Holý, Kamil ; Stará, Jitka ; Kocourek, František ; Ouředníčková, Jana ; Skalský, Michal ; Pultar, Oldřich
The publication summarizes the basic information about invasive pest species in fruit orchards, spreading to our country since 2000. Information about morphology, similar species, area of origin, distribution in Europe and Czechia, risk of introduction, life cycle, host plants, methods of monitoring and control, are provided for each pest species.
Fulltext:  PDF
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Population trends, threats and conservation of island endemic birds
Rohová, Kateřina ; Reif, Jiří (advisor) ; Sam, Kateřina (referee)
As endemics are considered plant and animal species including birds, which are in the focus of this thesis, that are found in a restricted geographic region and nowhere else in the world. Such endemics typically occur on the islands that are often recognized as important global biodiversity hotspots. However, many endemic species are very vulnerable due to numerous factors (mainly genetic and demographic) closely linked to the way of life on the islands. Huge effort is dedicated to their conservation, and it thus reasonable to ask whether such an effort made a significant contribution to prevent their loss. Here, I evaluate the overall success of island bird endemics conservation compared to continental conditions because such a global analysis has been lacking up to now. In addition, this thesis examines how three major threatening factors (namely habitat destruction, invasive species, and overexploitation) driven by anthropogenic activities affect population trends of continental and island bird species. Finally, I mapped and explained, using examples, which conservation tools are effective for supporting the populations of island endemic species. The results of statistical analyses, based on a global dataset containing almost 8000 avian species, showed that island endemic species are more...
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Legal regulation of alien species of plants and animals
Tisovská, Pavla ; Stejskal, Vojtěch (advisor) ; Damohorský, Milan (referee)
Legal regulation of alien species of plants and animals Abstract This thesis deals with the legal regulation of invasive non-native species of plants and animals, i.e., preventing their spread and minimizing the negative consequences that these species cause on individual ecosystems and biodiversity in general. The aim of this work is to analyse the related effective international, EU and Czech national legislation and to define the most significant changes concerning the relevant Czech laws in connection with the implementation of Regulation (EU) No. 1143/2014 and Regulation (EC) No. 708/2007. At the beginning, the work deals with the history of the spread of non-native species, as identifying the critical pathways of their spread is also an important knowledge necessary for creating effective legislation and also the definition of fundamental terms - non-native species, invasive non-native species, and biodiversity. Furthermore, the work deals with the most important international treaties in this area, i.e., the Convention on Biological Diversity, the Convention on the Conservation of Migratory Species of Wild Animals, the Convention on the Conservation of European Fauna and Flora and Habitats and the Madrid Protocol to the Antarctic Treaty, with the relevant European Union legislation, i.e., a network...
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Factors influencing diurnal activity of crayfish and its seasonality
Plasová, Kateřina ; Petrusek, Adam (advisor) ; Buřič, Miloš (referee)
Crayfish is mainly but not exclusively a nocturnal animal. The crayfish aktivity is taxon specific and can be further affected by various factors. The aim of this thesis is to create an overview of factors affecting the activity and to summarize their impact. Factors can be divided into those influencing daily activity and those influencing seasonal behaviour. This thesis focuses on discussing different reactions to the factors and its intensity by individual species. Insufficient data covering activity during the winter season offers an opportunity for further research. Key words: crayfish; daily activity; abiotic factors; biotic factors; seasonality
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Péče o travní porosty v rámci soustavy Natura 2000
Výletová, Lenka
Bachelor thesis was conceived in its first part as a general literature review describing history, significance and characteristic of grasslands within the system Natura 2000. Not only pastures are considered as a grassland, but also continuous vegetation with domination of grasses intended for feeding purposes and technical use, which perform production and non-production function. Grazing cattle is an essential element of protected areas. In a second part of the thesis I focuses on Natura 2000, its origin, directives and goals description. In separate chapters is mentioned the care of grasslands within the system Natura 2000 and description and destruction methods of invasive species. The third part is about selected Sites of Community Importance in Hodonín district. I chose and described five sites into Natura 2000 system around my home. These sites are described geologically, pedologically and botanically. I focused on a significant and vulnerable species in this areas. I focused on the recommended care for selected areas in the last part.
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