Paper concerns show of laboratory experiment program of the electricelectronic barrier application ingoing to Electronic Deterrent Fish System to its protection against negative influence of hydrotechnical facilities. Investigations have been performed at Hydraulic Laboratory of Wrocław University of Environmental and Life Sciences, and will be tend towards determination of optimal technical parameters of the tested facilities for specified hydraulic conditions within the water plants. The Union Water Instruction and national controls determined requirements fish protection of inland waters. Free two-environment fish migration in canalized rivers can be realised by water plant modernization based on construction of fish passes friendly for environmental and assembly of electricelectronic facilities as barriers. In our opinion these barriers should be enable fish migration upwards and downwards, and its localization and construction should be secure simpler passage across fish passes. This publication has been coasted from the research project means No. 00029-61535-OR0100002/06 on “Efficiency studies of the facilities to control of fish behaviour at inlets to water intakes and fish passes”, realised by Wrocław University of Environmental and Life Sciences. This project is financed by European Union and national budget in frame of Sectorial Operating System on “Fishery and Fish processing 2004-2006”. ...
The essential element of presented research is a description of the changes induced in the aquatic system as a result of human intervention by building barrage. The main objective of this study is to determine the differences in the quantity and condition of fish at the upper and lower station of the reservoir with regard to infected fish with Posthodiplostomum cuticola. Overall assessment of the species composition of fish at the upper and lower station of the reservoir in Brzeg Dolny allowed the quantitative analysis of fish in the Odra River. In the relevant section of the watercourse, the biggest fish of the carp family originated e.g. 89% of the total population. The study determines the overall health condition of fish at the lower and upper station. Particular attention was paid to changes in shell fish caused by vermines such as worm (Posthodiplostomum cuticola). Preliminary analysis, testing and a review of the literature data show the heterogeneous nature of the river ecosystem above and below grade on the Brzeg Dolny Reservoir. The barrage is an obstacle in the river which forms two separate living environments for fish, due to a significant difficulty in migrating between the upper and lower station, ...
River monitoring for the status and species composition of ichthyofauna is one of the forms of open water fisheries management. Research conducted on 10 selected for maintenance works of small rivers was to determine the composition and density of native and invasive fish and estimating the European Fish Index (EFI +) to assess the ecological status of designated sites in these rivers located in the Vistula and Oder basin. A total of 1405 fish, belonging to 24 species, were captured. Native species predominated, however, 19% of the fish caught were invasive species. The most common species was roach (Rutilus rutilus), but the most numerous was the gudgeon (Gobio gobio). At the researched stations, the maximum value of the EFI+ amounted to 0.868. After division into classes according to the value of the EFI + index, the majority of investigated sites where fish were found (24 of 28 sites), the EFI + value was between 0.00 to 0.40. This relatively small value indicated a poor condition of fish habitats, which was confirmed by low classes of ecological status at individual sites. Only in the case of the 1st position in the Tywa river and the 3rd position in the Czarna-Cedron ...
