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Potrava okouna říčního (Perca fluviatilis) v průběhu napouštění důlní propadliny Chabařovice (SZ Čechy, ČR)
Adámek, Zdeněk ; Jurajda, Pavel ; Musil, J. ; Janáč, Michal ; Kabilka, P. ; Polačik, Matej ; Ťuk, J. ; Valová, Zdenka ; Zeman, J.
The Chabařovice coal mining pit (Chabařovice lake) is currently still under the process of continuous flooding and its area increased up to 174 ha since 2001. The inflow water originates from surface waterbodies and hence the penetration of fish species, undesirable with respect to biomanipulation efforts, makes a serious problem in fisheries management of the lake. Adult perch have been the most numerous fish of the lake until 2004. Current perch population consists of one cohort (7+ - 8+) originating from the recruitment of two subsequent year classes. The food bulk of adult perch consisted of benthic animals and zooplankton in both years under study, however their proportion differed significantly. In 2004, dragon fly nymphs were the dominant food items with 58.80% proportion, followed by cladocerans Daphnia sp., which made up 23.82% of food ingested. In 2005, chironomid larvae prevailed in the food bulk with 41.95% and the diversity of ingested food items was obviously wider.
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