Endangered Fish Species in Balkan Rivers: Their Distributions and Threats from Hydropower Development
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Balkan Rivers Endangered Fish Species Distributions and threats from hydropower development 1 Balkan Rivers Endangered Fish Species Distributions and threats from hydropower development 1 Project Coordination & Writing Assoc. Prof. Dr. Steven Weiss, University of Graz, Institute of Zoology Universitätsplatz 2, A-8010 Contributions from Assoc. Prof. Dr. Apostolos Apostolou, Bulgarian Academy of Sciences Univ. Prof. Dr. Samir Đug, University of Sarajevo Dr. Zoran Marčić, University of Zagreb Dr. Anthi Oikonomou, Hellenic Centre for Marine Research Dr. Spase Shumka, Agricultural University of Tirana Univ. Prof. Dr. Predrag Simonović, University of Belgrade Dr. Daša Zabric, Hydrological Institute, Slovenia Technical Work (Preparation, Mapping, Layout, Artwork) M.Sc. Laura Pabst M.Sc. Peter Mehlmauer M.Sc. Sandra Bračun B.Sc. Ariane Droin Cover Page The upper Neretva River (A. Vorauer); marble trout (Salmo marmoratus) & Neretva spined loach (Cobitis narentana) (Perica Mustafić); map of distribution of the endangered softmouth trout (Salmo obtusirostris) Photo Credits Each photo is credited with the photographer’s name in the photo. For the following photographers, we additionally credit shutterstock.com: hdesislava, Dennis Jacobsen, Vladimir Wrangel, Rostislav Stefanek, Georgios Alexandris, Ollirg, Jasmin Mesic, Mirsad Selimovic, paradox_bilzanaca, Alberto Loyo, Alexandar Todorovic, bezdan, balkanyrudej, evronphoto, phant, nomadFra, Nikiforov Alexander, Irina Papoyan, Torgnoskaya Tatiana, Fesenko, Brankical, Sergey Lyashenko, Zeljko Radojko. Imprint This study is a part of the „Save the Blue Heart of Europe“ campaign (www.balkanrivers.net) organized by Riverwatch – Society for the Protection of Rivers (www.riverwatch.eu/en/) and EuroNatur – European Nature Heritage Foundation(www.euronatur.org). Supported by MAVA Foundation and Manfred-Hermsen-Stiftung. Proposed citation Proposed citation Weiss S, Apostolou A, Đug S, Marčić Z, Mušović M, Oikonomou A, Shumka S, Škrijelj R, Simonović P, Vesnić A, Zabric D. (2018). Endangered Fish Species in Balkan Rivers: their distributions and threats from hydropower development. Riverwatch & EuroNatur, 162 pp. February 2018 2 Contents EXECUTIVE SUMMARY ........................................................................... 4 Introduction .............................................................................................. 5 Background ............................................................................................... 5 Project scope .......................................................................................... 5 Legislation ............................................................................................ 7 Hydropower Sensitivity .......................................................................... 8 Distribution Data .................................................................................... 9 Hydropower impacts ................................................................................ 10 Environmental Impacts of Hydropower ................................................. 10 Types of facilities .................................................................................. 11 Fish passage .......................................................................................... 19 Karst systems ........................................................................................... 22 Species maps and fact sheets .................................................................... 23 Species Table ........................................................................................ 23 Non-Endangered Species of Importance ................................................. 109 Endangered Fish Hotspots ..................................................................... 118 Neretva Basin ..................................................................................... 118 Morača Basin (incl. Lake Skadar) ......................................................... 124 Drina-Tara Rivers ................................................................................ 131 Results and Discussion ............................................................................ 137 Recommendations .............................................................................. 140 List of abbreviations .............................................................................. 145 References ............................................................................................ 146 3 EXECUTIVE SUMMARY We reviewed the potential impact of large-scale hydropower expansion on the conservation status and extinction threat of 113 freshwater fish species on the Balkan Peninsula. Each of these species is listed in one of three IUCN threat categories and/or listed in one or more annexes of the European Habitats Directive or Bern Convention. For 81 of these species, GIS-based distribution maps have been overlaid with distributions of existing hydropower facilities (ca. 1,000), those in construction (ca. 180), or those planned (ca. 2,800) to explicitly demonstrate the spatial dimension of potential habitat loss. Based on these plans, we predict that up to 49 freshwater fish species are faced with either the threat of extinction or loss of between 50 and 100% of their Balkan distribution. Of these, eleven endemic species are threatened with extinction, seven will become critically endangered, and the number of endangered species will double to twenty-four. For 68 of 69 endemic species, habitat losses are estimated between 30 and 100%, resulting in increased levels of endangerment for essentially the entire endemic fauna. Additionally, the four migratory sturgeon species would essentially lose their potential for rehabilitation in the lower Danube if additional dams were constructed there. Three exemplary hotspots of biodiversity and threat were further described: The Neretva basin in Bosnia-Herzegovina and Croatia with fourteen listed species, the Morača/Skadar system in Montenegro and Albania with eleven listed species, and the Tara/upper Drina system in Montenegro and Bosnia-Herzegovina with nearly 200 kilometers of free-flowing riverine habitat. An additional six rivers of strategic conservation interest (the Sava in Slovenia and Croatia; the Kolpa on the Croatian-Slovenian border; the Una on the Croatian-Bosnian- Herzegovinian border, the Lim in Montenegro; and the Sana in Bosnia-Herzegovina) are described with respect to their length and value in conserving self-sustaining populations of key species, such as the endangered huchen. Several smaller rivers (Cetina River, Croatia; Kalamas River, Greece; Treska River, Republic of Macedonia) are discussed as critical habitat for species, whose global existence is endangered. 4 Introduction Background The Balkan Peninsula is a sub-region of the Mediterranean region, and as such, in the center of the world’s original 25 designated biodiversity hotspots (Myers 2000). For freshwater biodiversity, the Balkan region is the most important hotspot for both mollusks and fishes in Europe (Freyhof 2012). It also harbors Europe’s highest concentration of endemic fish species (Freyhof & Brooks 2011), whereby both species diversity and endemism can be further allocated into natural biogeographic units within the region (Oikonomou et al. 2014). Stretching from Slovenia to northern Greece (see Fig 1), the Balkan region contains 35,000 km of rivers (catchments > 500 km2), 80% of which are categorized to be either in pristine (ca. 30%) or good (ca. 50%) hydromorphological condition (Schwarz 2012). This is in stark contrast to the state of rivers in the rest of continental Europe, where, for example, a country like Austria reported only 6% of its river kilometers in pristine condition and 15% in good condition (Muhar et al. 1998). Despite the fact that the Balkan region has some of Europe’s most pristine rivers and is a global hotspot of biodiversity, the region is the target of one of the most ambitious hydropower expansion plans in the world, with currently up to 2,800 projects planned, over one third of which are located in protected areas, such as national parks (Schwarz 2017). As a building block for the Save-the-Blue-Heart-of-Europe campaign, this report aims to provide an exhaustive list of endangered freshwater fishes, their distributions and their level of vulnerability to hydropower expansion. The report builds upon a similar species-specific study on the vulnerability of Danube salmon (Hucho hucho) to hydropower expansion in the region (Freyhof et al. 2015) as well as a broader evaluation of endangered mollusks and fishes (Freyhof 2012). Project scope Geographically, the study considers the same region covered in Freyhof (2012) and Schwarz (2012), an area of ca. 450,000 km2 from Slovenia to northern Greece, including river basins south (i.e. right tributaries) of the Danube from Hungary to Bulgaria as well as Aegean Sea drainages of estern Turkey (see Fig 1., as well as http://www.balkanrivers.net/en/map). 5 Fig. 1. Area of investigation from Slovenia south to northern Greece and east along the Danube River including all right tributaries of the Danube along the Bulgarian border to the Black Sea, as well as the Aegean Sea coast along southern Greece and Turkey up to Istanbul. Taxonomically, obligate freshwater fishes including anadromous and catadromous species are considered, with an emphasis on riverine fishes, including lacustrine species that either require rivers for spawning, or whose