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Biodiverzita ryb v oblasti soutoku Moravy a Dyje - podpora a stabilizace populací vzácných a ohrožených druhů
Ústav biologie obratlovců AV ČR, v.v.i., Brno ; Halačka, Karel
Cílem projektu je získat na základě výzkumu biologie, ekologie a rozšíření vzácných a chráněných druhů ryb vědecké podklady pro návrh systémových aktivních zásahů v rámci cíleného managementu, který by vyloučil případný pokles a vytvořil podmínky pro stabilizaci a obnovu biodiverzity ichtyofauny v hydrologickém systému dolních toků Moravy a Dyje na území Biosférické rezervace "Dolní Morava". V roce 2007 byl vyhotoven podrobný mapový digitální podklad. bylo započato se shromažďováním i zanášením dat do jednotlivých vrstev podkladu. Realizována byla série terénních výjezdů, v jejichž rámci proběhl sběr ichtyologických dat, materiálu na molekulárně genetické analýzy u druhů a odlov potenciálního pokusného reprodukčního materiálu.
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The fish ladder on the Dyje river at Bulhary: the first year of operation
Klíma, Ondřej ; Lusk, Stanislav ; Lusková, Věra
In the autumn of 2007 a fish ladder started operating on the river Dyje near Bulhary (river km 39.9). It is a near-natural fish ladder of the "bypass" type. The bypass is 210 m in length, its longitudinal slope is 1 : 56, there are 29 rock bars, the difference in water levels above and below a bar being 0.1 m, and the water discharge is round 2 m3.s-1. The function of the bypass was monitored throughout 2008. In all, 25 fish species were ascertained, indicating perfect permeability of the bypass. The occurrence of Leuciscus cephalus, Chondrostoma nasus, Barbus barbus and Alburnus alburnus in the bypass was connected with their marked spawning migrations. Some of the L. cephalus and B. barbus staed in the bypass for long periods, as indicated by the presence of marked individuals. In that locality, the function of the bypass is affected by water discharge, those exceeding 50 m3.s-1 increasing the water level below the weir, the water filling the lower part of the bypass.
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The round goby, a new alien species found in the confluence of the Morava and Dyje Rivers (Czech Republic)
Lusk, Stanislav ; Bartoňová, Eva ; Lusková, Věra ; Klíma, Ondřej
In 2008, the occurrence of the Round Goby (Neogobius melanostomus) was ascertained in the confluence area of the Morava and Dyje Rivers. This non-native species invaded the hydrographic network of the Czech Republic through its own migration activity from the Danube. In 2009, the species is already common in that area. Successful reproduction of this species has been evidenced by the occurrence of yearlings. Genetic analyses of mitochondrial gene cytochrome b ascertained high proximity hereof gene among populations from the Dyje and Dnieper Rivers. One haplotype only has been identified in the Dyje River which was as compared with the studies of Doherty et al. (1996) and Stepien & Tumeo (2006), closest to haplotype A. Analysis of the first intron of ribosomal protein has revealed five haplotypes, AM1 – AM5. The haplotypes AM1 – AM4 formed a separate group with haplotype AHC3 (Neilson & Stepien 2009) from the region of the Dnieper River near Kiev.
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Revitalization of the Morava River vs. business plans
Halačka, Karel ; Mendel, Jan ; Papoušek, Ivo ; Vetešník, Lukáš
The course of the Morava River is an important supranational biocorridor with significant biological potential. This is attested also by results of recent ichthyological surveys. There is a plan of revitalization projects aimed at making migration barriers passable and also at repatriation of indigenous animal species. At the same time, there is a number of business plans focusing on the area, while their realization would severely restrain or even disallow the revitalization efforts. Therefore, a complex biological survey of the whole Morava River course should be performed first, and a detail project of naturalization of the floodplain, including the still existing fragments of original river channel, should be elaborated subsequently. Such project would then constitute a qualified basis for centrally assessed potential business plans.
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The latest findings concerning the species diversity of gudgeon of the genera Gobio and Romanogobio in the territory of the Czech Republic and Slovakia
Mendel, Jan ; Lusk, Stanislav ; Lusková, Věra ; Koščo, J. ; Vetešník, Lukáš ; Halačka, Karel
During last 15 years the taxonomy of gudgeon have undergone extensive changes. The findings important for preservation of ichthyofauna of the Czech Republic and Slovakia include confirmation of generic differentiation of the original genus Gobio into two genera Gobio and Romanogobio. On the basis of genetic analyses, the originally accepted uniform structure of the species Gobio gobio was divided into the structures which can be assigned the level of species (G. gobio, G. obtusirostris, G. carpathicus, Gobio sp.). The original R. albipinnatus can be divided into the species R. vladykovi and R. belingi. The original species R. kesslerii can be divided into R. banaticus and apparently also Romanogobio sp. With regard to newly acquired knowledge it is necessary to revise the system of efficient preservation of the biodiversity found in the above mentioned taxa. The areas of sympatric occurrence of some species were localized and hybridization within both the genera was demonstrated.
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Factors affecting the species composition of fish communities inhabiting sections of the rivers Morava, Dyje, Odra and Lužnice and their adjacent floodplains
Lusk, Stanislav ; Lusková, Věra ; Lojkásek, B. ; Hartvich, P.
The species composition of fish communities was studied in sections of the rivers Morava and Dyje (Black S. basin), Odra (Baltic S.), Lužnice (North S.) with floodplains. The following factors appear to determine the species composition of the ichthyofaunae inhabiting the hydrological regions: Sea basin, location of the section in the longitudinal profile of a stream, absence of migration barriers, presence of fishponds, fishery management. As regards the origin of a community, the pertinence to a basin is of greatest importance and migration from the lower sections. As regards the species richness of ichthyofauna, the region of confluence of the rivers Morava and Dyje is the richest of the whole Czech Republic - 38 native species, 9 of which occur only in that region, 7 alien species was recorded in that region. The region of the Odra R. was found to harbour 29 native and 4 non-native species; that of the Lužnice R., 25 native and 5 non-native fish species and 1 lamprey species .
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Large-scale rehabilitation in the alluvial area along the lower reaches of the Dyje River
Lusk, Stanislav ; Pražák, O. ; Lusková, Věra ; Halačka, Karel ; Vetešník, Lukáš
The Dyje River between Lednice and Bulhary was straightened, canalised, and provided with levees. Most of the alluvial area near Podivin was transformed to arable land. Due to elimination of floods, save for exceptions, areas denoted as wetlands and reed beds were qute dry for most of the year. As a result, the native fish communities typical of alluvial habitats gradually vanished from their habitats. In recent years, some 470 hectares on the left bank of the Dyje River, owned by a single private person, were transformed into a deer sanctuary. In the past two years, the arable land in that area has been gradually turned into meadows and a floodplain forest, together with restoring and enlarging the area of permanently waterlogged parts denoted as wetlands. As a result, the conditions permitting permanent occurrence of fish have been significantly improved and for a purposeful restoration of their fish communities in which native species predominate (the Carassius-Misgurnus type).
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Floodplains: special measures needed for the development and stabilisation of fish biota
Lusk, Stanislav ; Hartvich, P. ; Lojkásek, B. ; Lusková, Věra ; Pražák, O. ; Halačka, Karel ; Sovíková, L.
The preserved extent of the initial floodplains along major rivers is limited and has been distinctly altered by hydrological dynamics. The results exert a negative impact on aquatic biota, above all, fishes (the floodplains of Odra, Dyje, Lužnice rivers). The most marked changes include construction of ponds, canalization of streams with levees, absence of meadow management. The consequences: absent landscape formation activity of streams, expansion of wetland vegetation, gradual silting and downfall of alluvial habitats, their total drying, destruction of elements such as channels, ditches, river arms and other habitats, a limitation or disappearance of populations of Misgurnus fossilis, Rhodeus amarus, Cobitis spp., Carassius carassius, Leucaspius delineatus. Retrieval: maintenance of optimum condition of aquatic habitats, creation of artificial wetlands, restoration populations of protected fish species. Passive protection of habitat and species is no solution any longer.
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