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The Chabarovice coal mining pit arose by flooding the former strip mine area for brown coal. After filling, the pit area should reach about 225 hectare, total volume of water 34.4 mil. m3, average depth 15,6 meters with maximum of 23,3meters. It is assumed that the pond and adjacent areas will be used for recreation usage after completion of recultivation and ground shaping. I have performed the investigations in June and in August 2004 - 2005, using basic ichthyological methods. The data about recruitment were collected by the littoral seine net and adult fish (older than one year) were investigated by gillnets nets. Fish was determinated to genus, individually measured by slide caliper (fry) and by measuring plate (adult fish). The lenght of fish body (SL-standart lenght) was measured in millimeters and fish were weighted separately (W v g). In the year 2005, also scales were taken from individual fish for the age assesment. Obtained data were processed with regard to performed biomanipulation measures in individual sectores. Nine fish species and one hybrid were recorded by the monitoring with gillnets nets. The most numerous fish were juveniles and adults of rudd with SL 74 {--} 300 mm and the weight up to 618 g. The fish species with the strongest impact upon the pit ecosystem function is conitnuously the perch with the dominance of individuals with SL 46 to 337 mm and weight zup to 850 g.

Master of Science / Department of Biology / Craig Paukert / I evaluated sampling strategies and the effects of dike structure modifications in the lower Missouri River to better develop sampling and mitigation strategies to protect and enhance native river fishes. Sampling occurred in the lower 1,212 km of the Missouri River during October-June (coldwater season) and June-October (warmwater season) with stationary gill nets (GN), drifted trammel nets (TN), towed otter trawls (OT), and mini fyke nets (MF) from 2003-2006. We compared probabilities of detection (p), variability (coefficient of variation; CV) in catch per unit effort, and lengths for 25 species. Over 80% of adult large-bodied fishes were collected in GN during coldwater, >90% of chub spp. (Macrhybopsis) were collected in OT, and >90% of nine small-bodied and juvenile fishes were collected in MF. Trammel nets never had the highest p during coldwater, but had the highest or equally high p for 85% of adult large-bodied fishes during warmwater. Mean CV was lowest with GN for adult large-bodied fishes; chub spp. had the lowest CV in OT. Mean lengths were typically greater in GN and TN. Large river monitoring programs might best achieve the highest p, lowest variability, and widest size range of fishes by employing GN and OT during coldwater and TN, OT, and MF during warmwater sampling periods. We also compared fish community composition and the probability an un-notched and notched dike structure and channel sand bar (referred to as channel structures) was occupied by various fish species. Few differences in species richness and diversity were evident among channel structures. Notching a dike structure had no effect on proportional abundance for any habitat guild. Catch per unit effort (CPUE) was greater at notched dikes for only three (lake sturgeon Acipenser fulvescens, paddlefish Polyodon spathula, and shovelnose sturgeon Scaphirhynchus platorynchus) of 12 great river species. Occupancy at notched dikes increased for blue catfish Ictalurus furcatus and decreased for blue sucker Cycleptus elongatus, but did not differ for 17 (81%) other species. No distinct increase in occupancy at natural channel sand bars compared to engineered dike structures was evident. Mean CPUE was higher in dike structures than channel sand bars for four great river species (goldeye Hiodon alosoides, lake sturgeon, paddlefish, and shortnose gar Lepisosteus platostomus), but did not differ for ten. Our results suggest dike structures may provide necessary habitats for many fluvial species when compared to channel sand bars, but notching did not increase abundance or occupancy of most native Missouri River fishes.