The Journal is published by the Nature Conservation Agency of the Czech Republic in cooperation with the Cave Administration of the Czech Republic, the Krkonoše Mts. National Park Administration, the Bohemian Forest Mts. National Park Administration, the Podyjí National Park Administration and the The Bohemian Switzerland National Park Administration. It has been published since 1946.
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Nature Conservation 2/2009 — 21. 4. 2009 — Research, Surveys and Data Management — Print article in pdf
The Bečva River is a large tributary of the Morava River flowing from the Beskydy Mountains. In the main watercourse of the former river the Thick Shelled River Mussel (Unio crassus) and also other unionids occur rarely but numerous populations of the Unio crassus were found in five mill races flowing concurrently with the Bečva River main watercourse. The total number of individuals was estimated between 12,000 and 40,000 at all the five sites and it is the most numerous population of this bivalve in Moravia (eastern part of the Czech Republic, mostly the Danube River basin). Potential threats from habitat fragmentation, channel maintenance works, water level manipulation and water pollution are discussed.