Renewal of migration permeability in the fragmented river network of the Morava River drainage area

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