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Taubmann J.,Johannes Gutenberg University Mainz | Taubmann J.,Senckenberg Institute | Theissinger K.,Johannes Gutenberg University Mainz | Theissinger K.,Senckenberg Institute | And 8 more authors.
Conservation Genetics

Genetic diversity is one of the most important criteria to identify unique populations for conservation purposes. In this study we analyze the genetic population structure of the endangered montane mayfly Ameletus inopinatus in its European range. The species is restricted to unpolluted cold-water streams, and exhibits an insular distribution across highlands of Central Europe and a more continuous distribution across Fennoscandia and Northern Euro-Siberia. We genotyped 389 individuals from 31 populations for eight highly polymorphic microsatellite loci to investigate genetic diversity and population structure within and among European mountain ranges. Genetic diversity of A. inopinatus decreases along an east-west gradient in Central Europe and along a north-south gradient in Fennoscandia, respectively. Centres of exceptionally high genetic diversity are located in the Eastern Alps (Andertal Moor, Austria), the High Tatra, the Beskides, the Sudety Mountains and the Eastern German Highlands. Species distribution modelling for 2080 projects major regional habitat loss, particularly in Central Europe mountain ranges. By relating these range shifts to our population genetic results, we identify conservation units primarily in Eastern Europe, that if preserved would maintain high levels of the present-day genetic diversity and continue to provide long-term suitable habitat under future climate warming scenarios. © 2010 Springer Science+Business Media B.V. Source

Meraner A.,Research and Innovation Center | Unfer G.,Institute of Hydrobiology and Aquatic Ecosystem Management | Gandolfi A.,Research and Innovation Center
Knowledge and Management of Aquatic Ecosystems

In the last few decades, numerous populations of European grayling, Thymallus thymallus, have been suffering from stocking-induced genetic admixture of foreign strains into wild populations. Concordantly, genetic introgression was also reportedfor grayling stocks inhabiting the Upper Drava River, but all published genetic data based on specimens caught at least a decade ago, when stocking load was strong. Here, we applied mitochondrial control region sequencing and nuclear microsatellite genotyping to Upper Drava grayling fry collections and reference samples to update patterns and extent of human-mediated introgression. In contrast to previous data, we highlighted an almost genetic integrity of Drava grayling, evidencing limited genetic signatures of trans-basin stocking for grayling of Northern Alpine Danubian origin. Recent hybridisation was detected only twice among sixty-nine samples, while several cases of later-generation hybrids were disclosed by linking mitochondrial sequence to nuclear genetic data. The observed past, but very limited recent genetic introgression in grayling from Upper Drava seems to reflect shifting stocking trends, changing from massive introduction of trans-basin fish to more conservation-oriented strategies during the last 27 years. In a conservation context, we encourage pursuing the use of local wild grayling for supportive- and captive-breeding, but underline the need for genetic approaches in brood-stock selection programs. Finally, our integrated results from sibship reconstruction validate our strictly fry-based sampling scheme, thus offering a reasonable alternative also for other rheophilic fish species with similar life-history characteristics. © ONEMA, 2013. Source

Unfer G.,Institute of Hydrobiology and Aquatic Ecosystem Management | Hauer C.,Institute of Water Management | Lautsch E.,Institute of Hydrobiology and Aquatic Ecosystem Management
Ecology of Freshwater Fish

We monitored yearly recruitment (1997-2008) of brown trout (Salmo trutta) in a fourth-order Austrian Alpine river. The relative proportion of recruits to adult fish varied strongly among years (5.6-66.4%). These proportions were strongly correlated with specific flow patterns. High flows before and during the spawning period were positively correlated with recruitment, whereas high flows during incubation and emergence were negatively correlated with recruitment success. Unsteady flow modelling supported a causal hypothesis for these relationships in demonstrating that discharges >30m 3·s -1 resulted in substantial sediment motion (erosion and deposition) in suitable spawning areas within the study stretch. © 2010 John Wiley & Sons A/S. Source

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