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Should there be fishes in the water? - Ecological Educational program on the importance of water bodies without fish
BEČKOVÁ, Andrea
Water reservoir can be found anywhere in the nature. Small ponds without fish are difficult to be found. Biology students, members of biologically interested societies or wider public who is interested in environment can benefit out of these waters to learn more about relations between particular species, water and littoral plants and interactions between ranges of organisms. Fishing and fish farming do not have negligible impact on nutrition and relaxation of humans, but also they do not have negligible impact on life in waters Nowadays, the overly extended fish population is becoming the main problem that is causing fis predation which decimates pond environment. Fishless ponds are very important to provide environment for other aquatic insects and other organisms. It would be beneficial to devote more attention to the fresh water organisms at the school education through education programs or interest workshops and to have sufficient amount of suitable education resources. In this thesis, I describe relationships between organisms in fresh water reservoir, their relations with surroundings, which factors are influencing them and have impact on their occurrence.
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Exploatation characteristic of barbel, nase, chub and ide in the riverine and lake ecosystems
Prokeš, Miroslav ; Baruš, Vlastimil ; Peňáz, Milan
The exploatation characteristics of four potamodromous fish species, barbel (Barbus barbus), nase (Chondrostoma nasus), chub (Leuciscus cephalus) and ide (L. idus) obtained in the riverine and so-called lacustrine (man-made lake) ecosystem, exemplified on the fishing ground Dyje 7 on the river Dyje, is documented. Based on the analyse of many-year catch data of mentioned fish species, the influence of stream fragmentation was revealed upon the abundance reduction of natural populations of rheophilic fish species of concerning Dyje river sectin (located at the Mušov reservoir), as well as a necessity of strengthening these populations in the adjacent stream sections, especially by stocking of artificially produced fry, and in near future also by the construction of the new functional fish ladders.
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Alien fish species in the Odra basin on Moravien and Silesian
Lojkásek, B. ; Lusk, Stanislav ; Papoušek, Ivo
In the territory of Moravian and Silesian, the upper part of basin of the River Odra is found, where the riverine net is formed by smaller streams. The original ichthyofauna species structure is therefore, relative poor, representing 2 lamprey and 33 fish species, from which at present, 1 lamprey and 3 fish species are considered to be extinct. During the 19th and 20th centuries within human activities, 8 alien exotic species were introduced and 5 non-native species for this area were dislocated. All introduced and dislocated species are subject to fishery management. Regards to the fact that the species Carassius carassius and Pseudorasbora parva reproduce naturally, their relationships and influence are negative to the native species, they are assessed as invasive alien species.
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