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Telestes perspective on the karstic poljes of eastern Herzegovina
Doulíková, Tereza ; Vukićová, Jasna (advisor) ; Choleva, Lukáš (referee)
The Dinaric karst region in the Balkans is one of the hot spots of biodiversity with a high number of endemic freshwater fish. The major cause of the high degree of endemism are numerous paleoclimatic and geological events that have affected the formation of the entire area. Flows of karst poljes represent a specific ecosystem to which some fishes have adapted. The poljes have been periodically flooded and these floods may activate different underground channels, which lead to interconnection of poljes. These fish species spend a part of the year in surface water and a part in groundwater and they may use the underground flows between poljes for migration. The aim of this thesis is to evaluate the genetic variability of two endemic fish species of the genus Telestes living in karst poljes in the region of eastern Herzegovina, and to detect a possible current gene flow between populations of these species due to the connection of underground flows. For this purpose, the DNA from 102 individuals from five different localities was isolated. The mitochondrial marker cytochrom b and 16 microsatellite loci were used for the analyses. The results point to very low variability between species and populations. Based on mitochondrial marker analysis, no link between populations of the species was detected,...
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Development of endemic freshwater ichthyofauna of Greece
Kyralová, Eva ; Vukićová, Jasna (advisor) ; Švátora, Miroslav (referee)
The Balkans is one of the hot spots of biodiversity, and is known for a high diversity and endemism of freshwater fishes. The development of Greece was significantly affected by the climatic, geologic and orogenetic events resulting in high concentration of freshwater fish endemism. Some of the important historical events were the emergence of land bridges during the early Oligocene and Miocene, through which freshwater fishes dispersed to the Balkans from Asia and subsequently to Africa, the freshwater phase of the Paratethys sea or Alpine orogeny, which began 65 million years ago, and which gradually formed the Greek mountain systems, leading to a long-term isolation of local freshwater ichthyofauna and subsequent speciation. Other major events include Messinian salinity crisis and Pleistocene climate oscillations. Most of the freshwater fish families occurring in Greece most probably originated in the Southeast Asia, from where they colonized the Balkans by several routes. These colonizations took place repeatedly at different times and by different routes. The dispersion of freshwater fishes from Asia to Europe through Siberia started before the uplift of the Ural Mountains about 33 million years ago and continued until Pliocene. Another important colonization route from Asia was via the...
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Aquatic fauna of karstic fields in the Balkans
Doulíková, Tereza ; Vukićová, Jasna (advisor) ; Kalous, Lukáš (referee)
Dinaric Karst region of the Balkan Peninsula is one of the hot spots of biodiversity, and it is characterized by a high degree of endemism of freshwater fishes. Numerous geological and climatic events have influenced the formation of the area and speciation. Karst poljes are the specific features of Dinaric Karst. They represent a specific ecosystem full of endemic species, where hydrogeological processes play an important role. The periodic flooding appears on poljes. It leads to activation of various underground channels and their interconnection. Twenty two endemic fish species have adapted to this regime. They live in underground waters or in surface waters part of the year and they can migrate between poljes through karst channels. They show significant reduction in size and change in complexity of scaliness. Scales are small and they are barely visible in some species. All these species and abundant underground karst fauna are threatened primarily by pollution, habitat destruction, and drainage of poljes.
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Non-indigenous freshwater fish species of the Mediterranean basin of the Balkans
Balog, Štefan ; Vukićová, Jasna (advisor) ; Švátora, Miroslav (referee)
Mediterranean basin of the Balkan Peninsula is one of the hot-spots of biodiversity, with a high diversity of freshwater fishes and high degree of endemism. Introduction of non-native species greatly affects ecosystems and native species of fish. There were many reasons for introductions in the past. Aquaculture, sport fishing and ornamental fish belong to the most important reasons for introduction of non-native fish species. Altogether, 39 species belonging to 12 families were introduced in the Mediterranean basin of the Balkan Peninsula. Most of them belong to the families Cyprinidae and Salmonidae. Introduction of fishes was known since the Roman era. Although the first recorded introduction in this area was in the 13th century, most species were introduced in 20th century. The fishes were introduced from North America, Europe and Asia. Many translocations occurred in this area, too. Translocation is a relocation of particular species within one area. The most widespread introduced species in the Mediterranean basin of the Balkans are common carp (Cyprinus carpio), stone moroko (Pseudorasbora parva), rainbow trout (Onchorhynchus mykiss), mosquitofish (Gambusia holbrooki), goldfish (Carassius auratus) and sunfish (Lepomis gibbosus). Hybridization, competition, pathogen transmission and predation...
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Methods of study habitats and microhabitats preferences of freshwater fishes of Central Europe
Žák, Jakub ; Švátora, Miroslav (advisor) ; Drozd, Bořek (referee)
Small streams are a common habitat in Central Europe with unstable, rapidly-changing conditions. We can examine habitats on three different scales: microhabitat, mesohabitat and macrohabitat. Habitat preferences were among the fields of interest of Antonín Frič as he tried to describe the changing gradient of fish assemblages from source to the river's mouth on the macrohabitat scale. Habitat preferences are examined from a spatial point of view (substrate, depth, shelter), temporal point of view (season, day/night), biotic point of view (interspecies and intraspecies competition) and abiotic point of view (dissolved chemicals, velocity). For obtaining data of good quality, it is necessary to choose the right location and select the opti- mal strategy of examining fish assemblages (e.g. electrofishing, radiotelemetry, cameras). All variables which can affect habitat preferences in fish are measured. Multivariate statistical methods (e.g. PCA, RDA, CCA, CA) are used for evaluation of obtained datasets. Currently, we live in a fast developing period of this scientific area because of the need of evaluation of the human impact on freshwater biotope. The aim of this bachelor thesis is to introduce variables which influence habitat pref- erences of fish, to propose a modern review of methods commonly...
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The marketing fish research in the Czech Republic
LEVÁ, Lenka
The marketing fish research in the Czech Republic is directed to the sale of the fresh water fish, which are typical for our country. The consummation of fresh water fish has a long tradition in the Czech Republic, by contrast the marine fish are of the business in the modern life, which made possible to import this raw from the seaside country. In spite of the long term of the being fish in our market its consummation has got a low level. I directed above all to the young people and their board custums considering to the fish consummation in my dissertation. More than two third of inhabitants consumms fish, that means that it is a big chance for the motivation directed to the higher consummation of the fresh water fish. The Czech people eat much more salt water fish than fresh one. The reason is the wider choise of the salt water fish in the market , its better preparation for cooking purposes and lower prices than by the fresh water fish products. There is a low or almost no choice of the fresh water fish meals in the restaurants. With the boarder fish advertisiment by chefs and education it is possible to reach the more frequent using of fresh water fish in the reastaurant´s menus, which the young generation likes.
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