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The Drawa, a tributary to the Noteć River located in the Pomerania Lakeland, runs across the Drawska Primeval Forest, a large forest complex. In the past it was a natural transport route for trees cut in forested areas. The binduga was a place, where tree logs were transported, stored, thrown to the river and then logs were tied into rafts, and carried down the river. This practice was abandoned after the Second World War. The authors describe the way the logs were transported, system of bindugas along the Drawa and also refer to the artifacts of the ancient humans in the area where at present the Drawa National Park is located.
The Kamienna Hydropower Station on the Drawa River, located 32 km from its mouth, is the first barrage upstream from the sea. This obstacle prevents the further migration of anadromous fishes in this river system despite the fish pass that was installed when the dam was constructed a hundred years ago. The aim of the present study was to determine the effectiveness of the fish pass. Two methods were applied: occasional catches made at the fish pass excluding those from upstream waters (1997-1998); a Riverwatcher (VAKI Aquaculture Systems Ltd.) automatic fish counter that operated between September 2008 and June 2010. There was no significant fish migration through the pass, and only individuals of different species were noted at higher frequencies in late spring. Most offish were small, and the few large fish noted migrating in fall were identified as sea trout. Substantial differentiation in the ichthyofauna upstream and downstream from the dam suggests that exchange between these two areas is impossible. The results of this study confirm the inefficacy of the fish pass.
Part of the lower Drawa River between Dubie Lake and the Płociczna River mouth, stretching for a distance of 38.8 km, belongs to the Drawieński National Park, established in 1990. Electrofishing conducted on the 8 river stretches within the park limits yielded a total of 26 fish species and one cyclostomate species. The leading species appeared to be the roach, with the domination level reaching 56.16%. The other abundant species were: burbot (D = 7.81%), silver bream (D = 6.88%), and perch (D = 5.95%). The remaining species occurred in smaller numbers. The Drawa River within the Park limits is inhabited by 3 species of the family Cyprinidae: minnow-Phoxinus phoxinus, schneider-Alburnoides bipunctatus, and bitterling-Rhodeus sericeus amarus, all under strict protection and one cyclostomate species of the family Petromyzonidae-river lamprey-Lampetra fluviatilis, protected at the stage of larval development.
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