Conference Proceedings - IAD

Topic 3: Changes in biodiversity
Historical Distribution, current Situation and future
Potential of Sturgeons in Austrian Rivers
FRIEDRICH THOMAS
Institute of Hydrobiology and Aquatic Ecosystem Management, Max Emanuel Straße 17,
A-1180 Wien, phone +43 (1) 47 654 5200; fax +43 (1) 47 654 5217
thomas.friedrich@boku.ac.at
Keywords: sturgeons, sterlet, Austria, alien, Danube
Abstract
Worldwide, the family of sturgeons is near extinction. Reasons are different
human factors like energy production in rivers with the interruption of the river
continuum, the pollution of water bodies and overfishing because of the valuable
caviar.
The Danube has five native sturgeon species which partially used to migrate up
to the Bavarian Danube for spawning. The exact distribution of the various
species within the Danube remains still unclear. In the Austrian part of the
Danube only small quantities of the sterlet (A. ruthenus) can be found, which are
threatened with extinction. In the last years sturgeon stocking (accidentally and
on purpose) and catches increased throughout Austria. Unfortunately many of
these fish are of allochthonous sturgeon species. It is imminent to undertake
steps for protection and support of the remaining population of sterlet and to
evaluate other stretches regarding their potential of supporting a viable sterlet
population. Measures for reintroduction have to be closely monitored as stocking
programmes in the past didn’t have a significant impact on catches.
The objective of this study was to summarize all available data about sturgeons
in Austrian waters to get a picture of their historical and current distribution and
to use the gained data to evaluate the potential of Austrian rivers for sturgeons.
Materials and Method
For the historical distribution various texts books and sturgeon preparations of
the Museum of Natural History of Vienna have been analyzed concerning their
species and the location of their catch. With the gained information a database
and maps for the different sturgeon species were created, distinguishing actual
catch reports and general statements.
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