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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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Renewal of migration permeability in the fragmented river network of the Morava River drainage area
Lusk, Stanislav ; Lusková, Věra ; Klíma, Ondřej
The migration permeability of weirs for fishes is considered one of the strategic revitalisation measures which can significantly contribute to the restoration and stabilisation of fish biodiversity. It is inevitable to define priorities for the preparation and realisation of successive steps in this respect. In principle, the migration permeability should be renewed systematically, starting from the lowest lying migration barriers and proceeding upstream. Highest priority should be given to measures and constructions that are vital in renewing the occurrence and dispersion of native and mostly protected and rare species (Zingel zingel, Z. streber, Pelecus cultratus, Gymnocephalus schraetser, G. baloni, among others). High priority should be given to fish ladders which permit reproduction migrations (Chondrostoma nasus, Leuciscus idus, Lota lota, Vimba vimba, etc.), in which this is an important part of biology, and the condition of restoring stability of their populations.
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