Erschienen in: Aquatic Conservation : Marine and Freshwater Ecosystems ; 28 (2018), 3. - S. 587-599 https://dx.doi.org/10.1002/aqc.2878 River damming drives population fragmentation and habitat loss of the threatened Danube streber (Zingel streber): Implications for conservation Alexander Brinker1,2 | Christoph Chucholl3 | Jasminca Behrmann‐Godel2 | Michaela Matzinger4 | Timo Basen1 | Jan Baer1 1 Fisheries Research Station of Baden‐Württemberg, Langenargen, Germany Abstract ‐ 2 University of Konstanz, Konstanz, Germany 1. The Danube streber, Zingel streber, is a threatened and data deficient percid fish endemic to 3 EcoSurv, Schnaitsee, Germany the Danube catchment. The study provides the first data on distribution, life history, and ‐ 4 Office of the State Government of Upper genetic structure of the species at the upstream limit of its historic distribution (south western Austria, Linz, Austria Germany). Correspondence 2. A 3‐year survey effort with 143 fishing events identified several small, fragmentary popula- Alexander Brinker, Fisheries Research Station tions covering only 7% of the historical range of the species. Census population sizes (N )of of Baden‐Württemberg, Argenweg 50/1, c 88085 Langenargen, Germany. these subpopulations were estimated from mark–recapture data at <200 individuals. Effective Email:
[email protected] population sizes (Ne), calculated from genetic data (microsatellite genotyping), were much Funding information smaller still, at <15 individuals, resulting in an Nc/Ne ratio of <0.25, strongly indicating that Fischereiabgabe Baden‐Württemberg populations are seriously affected by genetic drift and inbreeding, and are thus facing a severe extinction risk. 3. Life‐history parameters recorded during the study indicate a rapid life cycle, with both sexes probably attaining sexual maturity at the age of 1 year or older.