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The Lim River, Montenegro, near the town of Andrijevica. It harbors self-sustaining populations of huchen at the most southern edge of its natural range. Rafting and fly-fishing have become particularly popular and lucrative in recent years for the local community. 

The Lim River, Montenegro, near the town of Andrijevica. It harbors self-sustaining populations of huchen at the most southern edge of its natural range. Rafting and fly-fishing have become particularly popular and lucrative in recent years for the local community. 

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Technical Report
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Citations

... Taking the high number of planned HPPs into account, it is not surprising that 45% of them are planned or built in protected areas (Schwarz, 2020). Weiss et al. (2018) predicted that eleven of the 69 endemic fish species inhabiting the region will potentially suffer extinction, if most or all planned hydropower projects are carried out. Additionally, a review by Huđek et al. (2020) showed that the monitoring stations at HPP in the Balkans, insufficiently assess the impact on macroinvertebrates communities, if at all. ...
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Although a large number of rivers stretches in Southeast Europe (SEE) have a pristine status compared to the rest of Europe, these ecosystems and their freshwater biodiversity are perceptibly threatened. Since crayfish species are known to cover a wide spectrum of ecological functions they are considered as keystone species and ecosystem engineers. Therefore, their decline may substantially impair local biodiversity and ecosystem services. In this manuscript we present a brief overview of the status of the native freshwater crayfish and their habitats in SEE. Different forms of physical habitat degradation as well as invasive alien crayfish species and their pathogens ( e.g. , Aphanomyces astaci ) are simultaneously threatening endangered populations all over SEE. Even though all native crayfish species are listed in the IUCN Red List, so far none of the 33 LIFE rehabilitation projects performed in SEE, has crayfish as target species in their agenda. Furthermore, SEE countries rarely designated Natura 2000 sites for native crayfish. We propose future studies to assess the distribution and functional role of crayfish species in SEE, as well as to develop habitat suitability models for these species during future conservation projects.
... Studies show that the habitat of the Arctic grayling T. arcticus is restricted due to dam constructions and habitat management should be analyzed according to "the new fragmented distribution" (Clarke et al., 2007). Assessments on species sensitivity to hydropower constructions are well known, but too few measures are taken for protection purposes (Weiss et al., 2018). Dispersal by the current-mediated drift of fish larvae is another issue influencing migration (upstream-downstream migration) (Zitek et al., 2004;Lechner et al., 2014). ...
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... In contrast to most European rivers, a high number of Balkan rivers are still in an excellent hydromorphological state and are therefore recognized as biodiversity hotspots [18,30]. Many authors propose that historically the European eel could access all rivers along the Adriatic and Aegean coasts [10,31]. ...
... Many authors propose that historically the European eel could access all rivers along the Adriatic and Aegean coasts [10,31]. Important Balkan rivers for the European eel include the Neretva in Croatia and Bosnia-Herzegovina, the rivers Strymon and Evros in Greece, and the river Morača in Montenegro [18]. Further records are available from the rivers Jadro, Žrnovnica, Sutorina, Bojana [32], Crna [33] Cetina and Ljuta [34]. ...
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The European eel (Anquilla anquilla) has been declining throughout its area of distribution, is addressed in several pieces of legislation, and is the target of extensive restoration efforts. Therefore, investigating and conserving natural eel habitats is urgently needed. Large, near-natural rivers have become rare in Europe but the Balkans host some of the extant examples. However, several Balkan rivers-among them the transboundary river Vjosa/Aoos of Albania and Greece-are under threat from planned hydropower constructions. This study synthesizes European eel catch data from four institutions and the results of a recent electrofishing survey. Population density and structure as well as habitat choice were studied at different spatial scales. We calculated densities for each meso-habitat (0-1303 ind./ha) and extrapolated these values across three different hydromorphological channel sections (meandering: 70 ind./ha, braided: 131 ind./ha, constrained: 334 ind./ha), resulting in an overall mean density of 168 ind./ha. Proposed hydropower plants would cut off about 80% of the catchment currently accessible and impact river sections downstream of the dams by disturbing hydrological dynamics. By linking study results to relevant legislation and literature we provide evidence-based data for water management decisions. We call for the Vjosa/Aoos to be protected in order to secure its outstanding conservation value.
... In contrast to most European rivers, a high number of Balkan rivers are still in an excellent hydromorphological state and are therefore recognized as biodiversity hotspots [18,30]. Many authors propose that historically the European eel could access all rivers along the Adriatic and Aegean coasts [10,31]. ...
... Many authors propose that historically the European eel could access all rivers along the Adriatic and Aegean coasts [10,31]. Important Balkan rivers for the European eel include the Neretva in Croatia and Bosnia-Herzegovina, the rivers Strymon and Evros in Greece, and the river Morača in Montenegro [18]. Further records are available from the rivers Jadro, Žrnovnica, Sutorina, Bojana [32], Crna [33] Cetina and Ljuta [34]. ...
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