Historical Distribution, current Situation and future Potential of Sturgeons in Austrian Rivers

Thomas Friedrich Supervisor: O.Univ.Prof. Dr.phil. Mathias Jungwirth

812.084 Masterseminar BOKU - University of Natural Resources and Applied Life Sciences Institute of Hydrobiology and Aquatic Ecosystem Management Vienna, Austria Contents

- Current situation and objective

- Method - Historical distribution, current situation and potential in

Salzach & Inn system

Danube in upper Austria Danube in lower Austria Thaya & March system other tributaries Drava

Mur - Summary

- Conclusions & open questions

2 Current situation and objective

- Very little existing knowledge about actual historic distribution of various sturgeon species in Austrian waters.

- The last remaining sturgeon species in Austria is highly endangered.

- Increased stocking and catch reports of native and non-native sturgeon species in recent years.

- Further intensification of sturgeon aquaculture will increase this trend.

- Successrate of stocking is unknown.

- Little knowledge about habitat use in Austrian rivers.

Objective: A synopsis containing as much available data about sturgeons in Austria as possible

3 Method

- Analysis of historical texts, catch reports and sturgeon preparates of the NHM

- Search for recent reports of sturgeon catches and stocking through fishing shops, governmental institutions, fishing magazines, internet platforms, private fish ecologists, fishermen and scientific organizations

- Determination of species and origin of stocked/caught fish in the various catchments

- Interpretation of gained data

4 Inn & Salzach Historic records

- Reports of catches from A. ruthenus (1890 - 1952) in the Inn upstream to Rosenheim (MAIER, 1908; MARGREITER, 1927; FISCHER, 1952; BROD 1980; STREIBL). - A catch of A. gueldenstaedtii is reported for the area around Ering in the year 1746 (BROD, 1980).

- Around the year 1800 there are records for a specimen of H. huso near Reichersberg (FREUDLSPERGER, 1936).

- A. ruthenus is claimed by some authors to occur rarely in the Salzach (AIGNER, 1859; PEYRER, 1874), while others say it occured often (FREUDLSPERGER, 1936). There is one reported catch in the area around Laufen (SIEBOLD, 1863). - One reported catch of H. huso around Tittmonig and one questionable catch of A. gueldenstaedtii in the same area (FREUDLSPERGER, 1936; HOCHLEITHNER, 1996; RATSCHAN & SCHMALL, 2011).

5 Inn & Salzach Stocking & Catch

Inn above PP Stammham Inn below PP Stammham Mouth of Salzach A. transmontanus 2002 1 2003 1 A. baerii 2004 2 A. gueldenstaedtii 2004 1 species unknown 2003/2004 2

6 Inn & Salzach Potential

14,2km

12,6km 13km 44 + 14,3km 16,4km

- The lower Inn has many powerplants and is therefore very smallfragmented. - Rhithralization through hydromorphological changes in the Salzach downstream of Laufen. - All recent catches occured in the most upstream section of the Inn.

7 Danube Historic records

- A. nudiventris was said migrate up to Komorn and to only seldom enter the Austrian Danube (FITZINGER & HECKEL, 1836). There is a reported catch near Vienna in the year 1936 (ZAUNER, 1997) and another catch near Regensburg, Bavaria (F & H, 1836), however the exact species of this specimen remains doubtful (SIEBOLD, 1863).

- A. gueldenstaedtii is reported as rare in the Austrian Danube, the farthest upstream record being a specimen near Regensburg 1679 (F & H, 1836).

- A. stellatus seems to have been the rarest sturgeon species in Austria (F & H, 1836; MOHR, 1952). SIEBOLD (1863) mentions the only record of the species in Bavaria in the Isar.

8 Danube Historic records

- A. ruthenus is stated as frequent in the lower Austrian Danube (F & H, 1836) with many catches near Vienna 1831 – 1960. In upper Austria and Bavaria some authors claim that it was a common species (F & H, 1836; HECKEL & KNER, 1857; KINZELBACH, 1994) while others say it was rare (LORI, 1871; KERSCHNER, 1956). Reports from catches range up to Ulm, the earliest record being in 1430 (F & H, 1836; SIEBOLD, 1863; JÄCKEL, 1864; KERSCHNER, 1956; WACHA, 1956; KINZELBACH, 1994; STREIBL).

- H. huso was said to be rare in the Austrian Danube by F & H (1836), however they point out that there were plenty of them in the middle ages. GAMLITSCHEK (1897) mentions catches near Tulln, other reports of single specimen come from Straubing in 1692 (F & H, 1836) and Vilshofen in 1605 (WACHA, 1956).

9 Danube upper Austria Stocking & Catch

Aschach Ottensheim Abwinden-Asten Wallsee-Mitterkirchen Ybbs-Persenbeug A. gueldenstaedtii 1996 unknown qty.

1984 1 1997 4 2002 3 2005 1 A. ruthenus 2006 4 2007 4 2008 2 2011 8 unknown 1 hybrid 2003 1 2006/07 5 1999 1 A. baerii 2006/07 1 1993 1 Polyodon spathula 2003 1 2002 1 species unknown 2010 1 2011 1 1

10 Danube upper Austria Stocking & Catch

11 Danube upper Austria Potential

27 + 4km 26,9 + 3,2km 15,7km 23,5 + 3,1km 40,1km 33,8km

- The impoundment Aschach is the home of the only self-sustaining population of A. ruthenus in Austria, with most catches directly below the powerplant Jochenstein. - Hybridization with A. baerii poses a threat to autochthonous sterlet populations. - Only small fragments of the tributaries are still connected to the Danube. - Recent catch of 2 sterlet specimen stocked in Germany (Schwarze Laber ~150km upstream)

12 Danube lower Austria Stocking & Catch

Melk Altenwörth Greifenstein Freudenau National Park Area unknown unknown qty. 1994 700 1700 A. ruthenus 2001 1000 2002-2005 7000 3000 2010 5 A. gueldenstaedtii 2005 300

unknown 1 1980 1 1986 1 1888 1 A. ruthenus 1990 2 1999 2 2000 6 2003 1 2011 1 hybrid 2002 1 unknown 1? 2005 1 A. baerii 2008 1? 2011 1 A. gueldenstaedtii 2001 1 2002 1 2005 1 species unknown 2009/2010 1 1 9 2011 1 3

13 Danube lower Austria Stocking & Catch

14 Danube lower Austria Potential

30,3km

57,7km 27,8km

22,1 + 3km 98,6 + 104,8km

- Most reported catches below the powerplants Altenwörth (mostly alien species) and Freudenau (mostly sterlets). - No catch reports above Freudenau after intensive stocking. - Middle to late 80s catch of a few small specimen of A. ruthenus near Klosterneuburg (before construction of PP Freudenau). - No reports about sterlet catches from the Hungarian section upstream of Gabcikovo (GUTI, pers. comm.). - Still high potential in the National Park/March/Thaya system.

15 March & Thaya Historic records

- Both A. gueldenstaedtii, A. ruthenus and H. huso are reported in the March and Thaya upstream to Lundenburg/Landshut (HEINRICH, 1856; JEITTELES, 1864; KRAFT, 1874; REMES 1902).

- MAHEN (1927) states that H. huso was rare in the March.

- Catches of H. huso in the area around Landshut are recorded by REMES (1902) and ZBORIL & ABSOLON (1916).

16 March & Thaya Potential

31,5 + 73,3 + 98,6km

- Both epi- and metapotamal character offer a greater possibility of habitat- availability for all life stages. - Longest connected, freeflowing river system in Austria. - Relatively few human impacts on the hydromorphology.

17 Other Tributaries Historic records | Stocking & Catch | Potential

- A. ruthenus was stated to rarely occur in the mouth of the river Enns (ANONYMOUS, 1884).

- No reports of other rivers could be found except for a few stocked fish in the river Vienna (FRAUENFELD, 1871).

Aschach Enns 1996 1 Polyodon spathula unknown 1

- Only very small stretches of Traun, Enns and Ybbs are still connected to the Danube. - Many powerplants and other barriers in the lower sections of these rivers, therefore very small fragmented. - Rhithralization through hydromorphological changes.

18 Drava Historic records | Stocking & Catch

- A. ruthenus was stated to occur in the Drava by MOJSISOVICS (1897) and HECKEL & KNER (1857), although its exact distribution within the Drava remains unknown.

Rosegg Feistritz Ferlach Annabrücke Völkermarkt Schwabegg Lavamünd 1982 130 130 1983 150 1987 70 300 A. ruthenus 1991 111 1995 90 2005 50 2010 300 A. gueldenstaedtii 2010 unknown qty.

1982 - 1993 3 2 5 11 17 4 3 A. ruthenus 1994 - 2003 1 1 species unknown 1994 - 2008 1 8 58 2 3

- Various oral reports by fishermen about juveniles in the impoundment Annabrücke (HONSIG-ERLENBURG & FRIEDL, 1999). - Discovery of a head capsule of a 5cm specimen 1998 in the impoundment Völkermarkt (HONSIG-ERLENBURG & FRIEDL, 1999).

19 Drava Potential

16,3km 6,1km

9,6km 10km 23,8km 13,4km 14,2km

10,2km

- As the various stretches are very short and the existing free-flowing sections are even shorter the Austrian Drava is rather unlikely to support a self- sustaining population of sterlet. - Possible exceptions: impoundments Annabrücke, Völkermarkt and Lavamünd.

- It is not sure that A. ruthenus ever occured in the Austrian Drava.

20 Mur Historic records | Stocking & Catch

- A. ruthenus was stated by MOJSISOVICS (1897) to occur in the Mur as far upstream as Graz (one reported catch in the Andritzbach 1890).

- A. gueldenstaedtii was stated for the area around Legrad (GLOWACKI, 1885).

Murau Graz Spielfeld

species unknown 2001 unknown qty. (A. ruthenus?)

2005 1 A. baerii 2010 2

21 Mur Potential

6,7km 4,2km 7,5km 3,9km 5,3km 4,7km 5,5km 21 + 110km 2,6km 12,3km

- Many powerplants and other barriers therefore very smallfragmented. - Rhithralization through hydromorphological changes in the area around Graz. - High density of aquaculture and fishing lakes in catchment. - Last stretch on the Austrian - Slovenian border offers a total lenght of ~130km and is connected to the Drava.

22 Summary Historic catches

A. gueldenstaedtii A. nudiventris A. ruthenus A. stellatus H. huso species unknown

23 Summary Recent catches 1980 - 2011

Danube Total 80 ind. 221 ind.

24 Summary Fragmentation and hotspots

25 Summary Conclusions

- Caught fish are in very good condition - Most catches occur directly below or a few kilometers downstream of powerplants - Efforts for protection and reintroduction should be bilateral (Austria, Germany, Slovakia, Slovenia, Czech Republic, Hungary, Croatia) - The Jochenstein population is a key factor regarding sustained reintroduction into other river stretches - Management of alien and extinct sturgeon species in some form seems inevitable - Reintroduction and stocking has to be scientifically monitored

26 Summary Open questions

- Identification of spawning sites and migration patterns in Jochenstein?

- Identification of possible spawning sites in other stretches?

- Effectiveness of stocking adults? homing factor -> stocking of fry/juveniles on spawning grounds a better solution?

- Possibilty of establishment of alien sturgeon populations?

- Sensitization of fishermen? Long snout-> sterlet short snout-> sturgeon

27 Cites Anonym, 1884: Rechenschaftsbericht des oberösterreichischen Fischerei- Vereines über das Jahr 1883. Mitteilungendes oberösterreichischen Fischerei- Vereines Jg. 4, Nr. 14: 87-91 Aigner, J. 1859: Salzburg`s Fische. Jahresbericht des vaterländischen Museums Carolino- Augusteum der Landeshauptstadt Salzburg. Brod, W. M. 1980: Historische Streiflichter auf Fisch und Fischerei. Im Dienste der Bayrischen Fischerei- 125 Jahre Landesfischereiverband Bayern e. V.: 173 - 237 aus H& W 1997 Fisch und Fang, 2000: Sterlet im Traunsee. Nr. 12/2000, S. 14 Fischer, H. 1952: Die Störe. Österreichs Fischerei 5. 1952 Seite 251 Fitzinger, J. A. und J. Heckel 1836: Monographische Darstellung der Gattung Acipenser. Annalen des Wiener Museums der Naturgeschichte, 1. Band, Wien. Frauenfeld, G. R. v, 1871: Die Wirbeltierfauna Niederösterreichs, Blätter des Vereins für Landeskunde von Niederösterreich 5, 108- 123 Freudlsperger H. 1936: Kurze Fischereigeschichtedes Erzstiftes Salzburg, Mitteilungen der Gesellschaft für Salzburger Landeskunde. Jg. 76, 77, Teil1+2 Haidvogl, G. und H. Waidbacher 1997: Ehemalige Fischfauna an ausgewählten österreichischen Fließgewässern. Universität für Bodenkultur, Institut für Hydrobiologie, Wien. Heckel, J. & R. Kner 1857: Die Süßwasserfische der österreichischen Monarchie mit Rücksicht auf die angränzenden Länder. Verlag von Willhelm Engelmann, Leipzig. Heinrich, A. 1856: Mährens und k.k. Schlesiens Fische, Reptilien und Vögel. Brunn Gamlitschek, A. 1897: Die Stadt Tulln und ihre Fischwässer von ehegestern und heute, aus Mitteilungen des österreichischen Fischerei- Vereins 17: 26- 33 Glowacki, J. Ed. 1885: Die Fische der Drau und ihres Gebietes. 16. Jahresbericht des Steierm. Landes Untergymnasiums zu Pettau, Pettau. Honsig- Erlenburg, W. und M. Friedl 1999: Zum Vorkommen des Sterlets (A. ruthenus L.) in Kärnten. Österreichs Fischerei, 52:129-133 Honsig- Erlenburg, w. und W. Petutschnig, 2002: Fische, Neunauge, Flusskrebse, Grossmuscheln. Natur Kärnten, Sonderreihe des Naturwissenschaftlichen Vereins für Kärnten, Klagenfurt. Hugo, A. 1886: Jagdzeitung 29 Jäckel, A. J. 1864: Die Fische Bayerns. Ein Beitrag zur Kentniss deutscher Süßwasserfische, Regensburg. Jeitteles, L. H. 1864: Die Fische der March bei Olmütz, aus Jahresbericht über das kaiserlich.- königliche Gymnasium in Olmütz während des Schuljahres 1864 Jungwirth, M., Schmutz, S. und H. Waidbacher 1989: Fischökologische Fallstudie Inn- Fischerbiologische Untersuchung im Hinblick auf Bewirtschaftungsfragen. Fischerei- Revierausschuß Innsbruck Stadt und Land, Wien. Kerschner, T., 1956: Der Linzer Markt für Süßwasserfische insbesondere in seiner letzten Blüte vor dem ersten Weltkrieg Kinzelbach, R. 1994: Ein weiterer alter Nachweis des Sterlet in der Baden-württembergischen Donau. Biologie der Donau. Kiwek, F., 1995: Sterlet Programm. Österreichs Fischerei 48: 2-3 Kraft, C. 1874: Die neuesten Erhebungen über die Zustände der Fischerei in den im Reichsrate vertretenen Königreichen und Ländern. Mitt. a. d. Gebiete d. Statistik Jg. XX/IV, Wien. Lori 1871: Die Fische in der Umgegend von Passau. Beiträge zur Fauna Niederbayerns Mahen, J. 1927: Castecna revise ryb dunajske obiasti. Sbornik Klubu Pirodovedeckeho v Brne, Vol. 9. Margreiter, H., 1927: Ein Sterlet im Inn gefangen. der Tiroler Fischer 2, S.94 Mohr, E., 1952: Der Stör . WestarpWissenschafften- Verlagsgesellschaft, 65 S. Mojsisovics, A. v. M. 1897: Das Thierleben der österreichisch-ungarischen Tiefebenen. Alfred Hödler, Wien. Österreichs Fischereiwirtschaft, 1936: Fang eines großen Störes in Wien. IV Jahrgang; S. 69. OÖ Landesfischereiverband 1996:Mitteilungen des OÖ LFV. Juni 1996, Linz. OÖ Landesfischereiverband 1996:Mitteilungen des OÖ LFV. Dezember 1996, Linz. Peyrer, C. 1874: Fischereibetrieb und Fischereirecht in Oesterreich. Wien, Ackerbauministerium Reinartz, R. 2008: Artenhilfsprogramm Sterlet- Abschlussbericht 2004 - 2007. Landesfischereiverband Bayern, Münster. Remes, 1902: Die Fische der March Schmall B. und C. Ratschan 2011: Die historische und aktuelle Fischfauna der Salzach - ein Vergleich mit dem Inn. Beitrag Naturkunde Oberösterreichs 21, 55- 191 Siebold C. T. E., 1863: Die Süßwasserfische von Mitteleuropa. Verlag von Willhelm Engelmann, Leipzig. Spindler, T., 1997 : Fischfauna in Österreich. Bundesministeriumfür Umwelt, Jugend und Familie, Wien, 148 S. Streibl, D. (ohne Datum): Über den Sterlet. Privatarchiv Huber, vermutlich aus AFZ. Wacha, G., 1956: Fische und Fischhandel im alten Linz, Naturkundliches Jahrbuch der Stadt Linz Zauner, G., 1997: Acipenseriden in Österreich. Österreichs Fischerei, 50: 183-187. Zborˇil, J. & K. Absolon 1916: Zoologicka´ pozorova´nı´ z okolı´ hodonı´nske´ho (Zoological observation from the Hodonı´n region).Cˇ asopis moravske´ho musea zemske´ho 15: 3–12.

Additional Data: Hans-Peter Angerer, Josef Dellinger, Jürgen Eberstaller, Robert Elsbacher, Georg Fürnweger, Martin Hochleithner, Wolfgang Honsig-Erlenburg, Lucia Jirku, Mathias Jungwirth, Rudolf Kovarik, Harald Kromp, Heinz Machacek, Matthias Maier, Günther Parthl, Wolfgang Petrouschek, Alfred Pleyer, Siegfried Pilgerstorfer, Clemens Ratschan, Heinz Renner, Klaus-Jürgen Rudowsky, Walter Saltzmann, Ursula Scheiblechner, Bernhard Schmall, Herwig Waidbacher, Franz Wiesmayer, Christian Wiesner, Gerald Zauner, Bernhard Zens

Jänner 12 28 Thanks for your attention!

If you've ever had a chance to look into the eyes of a sturgeon, there are unfathomable depths there that take you back millennia; they take you back ages and ages ago. And having looked into the eyes of a sturgeon, you can fully understand that these animals swam practically unchanged from the way they are today when dinosaurs walked the earth Christopher Letts, Hudson River Educator

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