Regional structure despite limited mtDNA sequence diversity found in the endangered Huchen, Hucho hucho (Linnaeus, 1758)
We evaluate the hypothesis of no geographic structure in the Huchen (Hucho hucho), a large, predatory salmonid endemic to the Danube basin. Forty-seven individuals sampled from throughout the Huchen’s native range were genetically characterized. Extremely limited sequence diversity across 1,800 bases of mtDNA (the complete control region and partial NADH-1 subunit) evidenced by four closely related mtDNA haplotypes was found. Nonetheless, the geographic distribution of mtDNA repeats (5–10, 82-bp long copies per individual) as well as allelic diversity across two microsatellite loci indicated large-scale geographic structure between the north-western (Austria and Slovenia) distribution area and eastern (Slovakia and Ukraine) or southern (Bosnia-Herzegovina and Montenegro) sample sites. An extremely slow rate of substitution for the H. hucho mtDNA is considered along with the alternative hypotheses to explain the limited mtDNA diversity. Considering the regional genetic structure implied by our data, we advocate restrictions on the transport of brood fish or yearlings across the range of the species distribution and sale of Huchen across international boundaries. Future genetic analysis to support local conservation and monitoring efforts must focus on developing a high-resolution screen that may be applied to identify hatchery versus naturally reproduced individuals in the wild.
KeywordsDanube salmon Danubian basin Phylogeography Microsatellites mtDNA
Thanks go to Fisheries Research Institute of Slovenia, I. Bogut, M. Červek, D. Mrdak, R. Šanda, M. Živković, G. Unfer, Institute of Hydrobiology and Aquatic Ecosystem Management, and Thomas Friedl and W. Honsig-Ehrlenburg, Environmental Department of the Provincial Government of Carinthia. This work was supported by the Slovenian Research Agency and Ministry of Science and Technological Development of the Republic of Serbia (Grant No. 173025) and the Institute of Zoology, Karl-Franzens University of Graz.
- Berg, L. S., 1949. Freshwater Fishes of the USSR and Neighbouring Countries (Vol. 3). Academy of Sciences of USSR, Moscow, Leningrad (in Russian).Google Scholar
- Bernatchez, L. & R. G. Danzmann, 1993. Congruence in control-region sequence and restriction-site variation in mitochondrial DNA of brook charr (Salvelinus fontinalis Mithcill). Molecular Biology and Evolution 10: 1002–1014.Google Scholar
- Casgrain, P. & P. Legendre, 2001. The R package for multivariate and spatial analysis version 4.0. Université de Montréal. http://www.fas.unmontreal.ca/BIOL/legendre.
- Groombridge, B., 1994. IUCN Red List of Threatened Animals. IUCN, Gland.Google Scholar
- Hauer, W., 2003. Fazination Huchen. Vorkommen, Fang, Anekdoten. Stocker Verlag, Graz. (in German).Google Scholar
- Holčik, J., 1990. Conservation of the huchen, Hucho hucho (L.), (Salmonidae) with special reference to Slovakian rivers. Journal of Fish Biology 37(Suppl. A): 113–121.Google Scholar
- Holčik, J., K. Hensel, J. Nieslanik & L. Skacel, 1988. The Eurasian huchen, Hucho hucho: largest salmon of the world. Perspectives in Vertebrate Science 5: 239.Google Scholar
- Karaman, S., 1926. Salmonidi Balkana. Bulletein de la Societé Scientifique de Skoplje 2: 253–268.Google Scholar
- Langella, O., 2002. Populations, 1.2.28 (12/5/2002) Copyright (C) 1999, Olivier Langella, CNRS UPR9034.Google Scholar
- Schmutz, S., A. Zitek, S. Zobl, M. Jungwirth, N. Knopf, E. Kraus, T. Bauer & T. Kaufmann, 2002. Integrated approach to the conservation and restoration of Danube salmonid, Hucho hucho, popualtions in Austria. In Collares-Pereira, M. J., M. M. Coelho & I. G. Cowx (eds), Freshwater Fish Conservation: Options for the Future. Fishing News Books. Blackwell Science, Oxford: 157–173.Google Scholar
- Vasil’eva, E. D., 2003. Main alterations in ichthyofauna of the largest rivers of the northern coast of the Black Sea in the last 50 years: a review. Folia Zoologica 52: 337–358.Google Scholar