Dipl. Biol. Jörn Geßner

IGB, Dept.4,
Biology and Ecology of Fishes 
12587 Berlin, Müggelseedamm 310

Fields of Interests:

Biology and Ecology of sturgeons, Fisheries Management, Aquaculture

Tel: (030) 64 181 626
Fax: (030) 64 181 626

sturgeon@igb-berlin.de

1. Remediation of Atlantic sturgeons in central European waters – establishment of broodstocks

The work is carried out in a cooperation with Fisch und Umwelt Mecklenburg-Vorpommern e.V. (Dipl. Biol. G. M. Arndt); Regional Research Institute for Agriculture and Fisheries Mecklenburg-Vorpommern (LFA-MV), Born/Darß (Dr. E. Anders), the CEMAGREF, Bordeaux (Dr. E. Rochard), Huntsman Marine Science Centre, St. Andrews, NB, Canada, Socièté de la Faune et des Parcs de Quebec, QC, Canada.

In German waters the Atlantic sturgeons are considered missing (Acipenser sturio, North Sea) or extinct (Acipenser oxyrinchus, Baltic Sea). The remediation efforts for Acipenser sturio are based on an ex-situ measure leading to the development of a broodstock. In a cooperation with the French CEMAGREF young of the year A. sturio have been transferred from France to Berlin in 1996. These fish have grown up to 1.4 m and 8-15 kg in weight. A first reproduction of these fish is anticipated in the upcoming years.

For Acipenser oxyrinchus a broodstock is established from wild caught fish as well as of fish originating from controlled reproduction in Canada. Subsequent reproduction and rearing of fingerlings is performed since 2001. In cooperation with S. Würtz and W. Kloas (Dept. V), the background for the reproduction of captive sturgeons is one focus of the current research. The in depth understanding of control mechanisms (endogenous and exogenous) for reproductive processes is vital.

2. Population genetics of Atlantic Sturgeons / Genetic diversity of broodstocks

In collaboration with the Institute of Biochemistry and Biology, Evolution Biology/Special Zoology, University of Potsdam (Prof. Dr. R. Tiedemann), the Institute for Zoo and Wildlife Research (Dr. A. Ludwig) and the CEMAGREF, Bordeaux (Dr. E. Rochard) population genetics of Atlantic sturgeons are investigated. The work by Dr. Ludwig (now IZW-Berlin) uncovered that the Baltic Sea was populated by the American Atlantic sturgeon rather than the European Atlantic sturgeon for more than 800 years. Since 2003, the work focuses on the mechanism of the replacement of A. sturio by the American Atlantic sturgeon. Furthermore, studies to characterize the broodstocks of both species are carried out as a prerequisite for the development of a genetic breeding plan, aiming at the conservation of genetic heterogeneity in the subsequent generations.

3. Rearing techniques and feed optimization for long term rearing

Long term rearing is required to allow sturgeons to reach maturity. Generation cycles of 8-15 years make it necessary to improve the rearing practice to avoid adverse impacts upon behaviour or physiological traits. Within the aquaculture programme of Dept. V optimization of rearing techniques is attempted to provide guidance for the future expansion of the stocks. Feed selectivity – being reported in both Atlantic sturgeons - is very pronounced in A. sturio, influencing the rearing attempts of the ex-situ stock. In order to promote growth and improve the wellbeing of the broodstock over long rearing periods, enhancing maturation, the optimization of the diet is one of the prime aims.In order to improve the fitness for survival in those fish designated for release in the wild, adaptation of rearing techniques and feeding regimes are an important key to reduce selection for intensive rearing and to facilitate adaptation upon release. The development of suitable techniques is considered to be of vital importance for the subsequent transfer of rearing tasks to commercial rearers in order to produce sufficient numbers of fish for stocking.

4. Habitat selectivity of sturgeon

Habitat availability plays a mayor role as a prerequisite for the development a self sustaining population of the species. Sturgeons are reported to have been the first species to respond to the anthropogenic changes of the river structure and water quality in the 19th century. Considering the diversity of habitats these fish utilize during their life cycle, as well as for their longevity they provide an ideal indicator for mainstem river ecosystems. In order to develop an understanding of the requirements, telemetry studies are currently conducted to outline the habitat preferences. Embedded in the Large River Program at IGB the underlying driving forces for the persistence of these habitat types are to be identified.

Provided that sturgeon reveal a strong homing behaviour, the selection of suitable river stretches allowing reproduction of the returning fish following their maturation is a key element of the preparation of the restoration measures. Investigations on the Odra River and its tributaries Wartha, Prosna and Drawa have been carried out based on the data of historic spawning sites. The criteria for the evaluation include abiotic parameters such as substrate characteristics, hydrological parameters, water quality criteria, and migration obstacles. Similar investigations are continued for the Elbe River focusing on the lower and middle part of the river as well as its tributaries Stör and Oste.

Associated with Department V experimental studies are performed to gain insight to the ecology, behaviour, and physiology of early ontogenetic stages initially of Atlantic sturgeons and in cooperation with Cemagref to be continued with A. sturio. Since these stages are considered the bottleneck for population development, characteristics such as substrate selectivity and their physiological effects are investigated.

European Atlantic sturgeon tagged for release in Elbe River (September 2008)

The first releases of A. oxyrinchus in the Odra river catchment were begun in 2006 as well as with A. sturio in the Elbe River in 2008. Repeated releases of tagged fish as well as individuals equipped with ultrasonic transmitters are utilized to identify the migration behaviour as well as habitat preferences and adverse impacts upon the released fish. The results are used to verify the habitat requirements of the species, thus leading to criteria for the assessment of recipient water bodies and their management. Thereby, the results are providing a major input on the development of a national Action Plan for sturgeon restoration as required by the Bern Convention since the amendment of the international Action Plan in November 2007.

The integration of the abiotic parameters in a model will be attempted as a second Step to allow a simulation of the conditions leading to the required structures. This would allow a more precise assessment of planned constructions and an early integration of the requirements of fish communities into such measures.

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Society to Save the Sturgeon e.V., Board of Directors since 1994

HELCOM Habitat PG Restoration of Baltic sturgeon, chairman since 1997

Malaspina University College Sturgeon Research Centre, Scientific Advisory Committee since 2005

Reviewed Journals

1. Arndt, G.M.; Gessner, J.; Bartel, R. 2006. Characteristics and availability of spawning habitat for Baltic sturgeon in the Odra river and its tributaries. J. Appl. Ichthyol.22 (Suppl. 1): 172-181.

2. Arndt, G.-M., Gessner, J., Raymakers, C. 2002. Trends in farming, trade and occurrence of native and exotic sturgeons in natural habitats in Central and Western Europe. J. Appl. Ichthyol., 18, 4-6, 444-449.

3. Fredrich, F., Kapusta, A., Ebert, M., Duda, A., Gessner, J. 2008. Migratory behaviour of young sturgeon, Acipenser oxyrinchus in the Oder River catchment - Preliminary results of a radio telemetric study in the Drawa River, Poland. Pol. Arch. Fish. Sci. in press.

4. Gessner, J. 2000. Restoration programmes for Acipenser sturio in Europe. In: Elvira, B. et al. (Eds). Proceedings of the 1st Symposium on Conservation of the Atlantic Sturgeon Acipenser sturio in Europe, 6-11 September, 1999, Madrid & Sevilla, Spain. Bol. Inst. Esp. Oceanogr. 16(4): 117-126.

5. Gessner, J.; Arndt, G.M. 2006. Modification of gill nets to minimize by-catch of sturgeons. J. Appl. Ichthyol. 22(Suppl. 1): 166-171.

6. Gessner, J.; Arndt, G.M; Ludwig, A.N.; Kirschbaum, F. 2007. Remediation of Atlantic sturgeon Acipenser oxyrinchus in the Baltic Sea - Background, Status, and Perspectives. American Fisheries Symposium 56: 301-317.

7. Gessner, J., Bartel, R. 2000. Is there still suitable habitat for sturgeons in the Odra River tributary? In: Elvira, B. et al. (Eds). Proceedings of the 1st Symposium on Conservation of the Atlantic Sturgeon Acipenser sturio in Europe, 6-11 September, 1999, Madrid & Sevilla, Spain. Bol. Inst. Esp. Oceanogr. 16(4): 127-139.

8. Gessner, J., Debus, L., Filipiak, J., Spratte, S., Skora, K.E. and G.M. Arndt. 1999. Catches of sturgeons in German and adjacent waters since 1980. Journal of Applied Ichthyology 15(4): 136-142

9. Gessner, J., Horvath, A., Arndt, G.-M., Urbányi, B., Anders, E., Hegyi, A., Wuertz, S. 2008. Intercontinental air transport of adult A. oxyrinchus – impact assessment of transport conditions and pressure changes on blood parameters. J. Appl. Ichthyol. In press.

10. Gessner, J., Kamerichs, C.M., Kloas, W., Wuertz, S. Submitted. Behavioural and physiological responses in early life phases of Atlantic sturgeon (Acipenser oxyrinchus Mitchill 1815) towards different substrates. J.. Appl. Ichthyol. Subm.

11. Gessner, J., Van Eenennaam, J. P. Doroshov, S. J. 2007. North American green and European Atlantic sturgeon: comparisons of life histories and human impacts. Env. Biol. Fish.

12. Kirschbaum, F., Gessner, J. 2002. Perspectives for the re-introduction of the European sturgeon, Acipenser sturio L., in the river Elbe system. Perspektiven der Wiedereinbürgerung des Europäischen Störs, Acipenser sturio L., im Einzugsgebiet der Elbe. Zeitschr. Fischkunde, Suppl. 1, 217-232.

13. Kirschbaum, F., Gessner, J. 2000. Re-establishment programme for Acipenser sturio: the German approach. In: Elvira, B. et al. (Eds). Proceedings of the 1st Symposium on Conservation of the Atlantic Sturgeon Acipenser sturio in Europe, 6-11 September, 1999, Madrid & Sevilla, Spain. Bol. Inst. Esp. Oceanogr. 16(4): 149-156.

14. Kirschbaum, F., Gessner, J., Hensel, E. & Williot, P. 2000. Broodstock management: The case Acipenser sturio. Symposium on Caviar Production Recent Developments & Future Trends in Breeding, Conservation and Product processing of Sturgeons, 12-15 March, 2000, Berlin, Germany.

15. Kirschbaum, F., A. Ludwig, E. Hensel, S. Würtz, W. Kloas, P. Williot, R. Tiedemann, G.-M. Arndt, E. Anders, H. von Nordheim, and J. Gessner. 2004. Status of the Project on Protection and Restoration of Atlantic Sturgeon in Germany: background, current situation, and perspectives. Pages 36-53 in J. Gessner and J. Ritterhoff, editors. Species differentiation and population identification in the sturgeons Acipenser sturio L. and Acipenser oxyrinchus. BfN Skripten 101: 122pp.

16. Ludwig, A.L., Gessner, J. 2007. What makes the difference – sea sturgeons on both sides of the Atlantic Ocean. American Fisheries Society Symposium 56: 285-300.

17. Ludwig, A., Pitra, C. Congiu, L., Gessner, J., Fickel, J., Fontana, F., Paternello, T., Zane, L. 2003 Conservation implications as indicated by the genetic structure of a critical endangered sturgeon species - the Adriatic sturgeon, Acipenser naccarii. Molecular Conservation 12(12): 3253-3264.

18. Tiedemann, R., Moll, K., Paulus, K., Scheer, M., Williot, P., Bartel, R., Gessner, J., Kirschbaum, F. 2007. Atlantic sturgeons: American females successful in Europe. Naturwissenschaften 3(2007): 5pp

19. Wirth, M., Kirschbaum, F., Gessner, J., Krüger, A., Patriche, N., Billard, R. 2000. Chemical and biochemical composition of caviar from different sturgeon species and origins. Nahrung/Food, 44 (4), 233-237.

20. Wirth, M., Kirschbaum, F, Gessner, J., Williot, P., Patriche, N., Billard, R. 2002. Fatty acid composition in Sturgeon caviar from different species: comparing wild and farmed origins. Internation. Rev. Hydrobiol. 87, 5-6, 629-636

21. Würtz, S., Gessner, J., Kirschbaum, F., Kloas, W. 2002. First identification of IGF-I mRNA in the Genus Acipenser and its quantification in maturing gonads. Proceedings of the 21st Conference of European Comparative Endocrinologists, Bonn, Germany, 26.-30.08.2002, Monduzzi Editore, 253-257.

22. Würtz, S., Nitsche, A., Gessner, J., Kirschbaum, F., Kloas, W. 2006. IGF-I system and its role in maturing gonads of female sterlet, Acipenser ruthenus Linneaus, 1758. J. Appl. Ichthyol. 22(Suppl. 1): 346-352.

23. Würtz, S., Gessner, J., Hogans, B., Löschau, P., Kirschbaum, F., Kloas, W. 2006. The influence of rearing density as environmental stressor on cortisol response of shortnose sturgeon (Acipenser brevirostrum). J. Appl. Ichthyol. 22(Suppl. 1): 269-273.

unreviewed

1. Arndt, G.-M., Gessner, J. 2005. Aufbau eines Elterntierbestandes als Grundlage für die Wiedereinbürgerung des Störs im Ostseeeinzugsgebiet. Jahresheft 2003/2004 des Vereins Fisch und Umwelt Mecklenburg-Vorpommern e.V.9-18.

2. Gessner, J., Arndt, G.M. 2003.Der Stör – ein Beispiel für die besondere Gefährdung von Wanderfischarten. In: Fische und Fischerei in Nord- und Ostsee. Meer und Museum 17: 167-175.

3. Gessner, J., Arndt, G.M., Anders, E. und Kirschbaum, F. 2004. Perspektive der Wiedereinbürgerung der Atlantischen Störe in Nord- und Ostsee. Mitteilungen des Bundesamtes für Seeschifffahrt und Hydrologie. 139-151

4. Gessner, J., Arndt, G.M., Kirschbaum, F., Anders, E., Ritterhoff, J., v. Nordheim, H. 2005. Wiedereinbürgerung der Störe (A.cipenser sturio L. 1758, und A. oxyrinchus, Mitchill, 1844) in Deutschland – aktueller Status. BfN Skripten 140: 150pp.

5. Gessner, J., Kirschbaum, F. 2005. Die Rückkehr der Störe – Wanderfische rücken in den Fokus der Umweltpolitik. Naturmagazin 2005

6. Gessner, J., Ludwig, A., Diekmann, M. (2006): Störe: Implikationen für Schutz und Management. Fischer und Teichwirt 2/2006:63-64

7. Gessner J., v. Nordheim H., 1998. Die Wiedereinbürgerung des gemeinen Störs (Acipenser sturio L.) in der Oder benötigt die bilaterale Kooperation in Forschung und Fischereimanagement. Ergebnisse des deutsch-polnischen Seminars zur fischereilichen Bewirtschaftung des Stettiner Haffs und der pommerschen Bucht. Rostock, 8-10.12.1997: 16-18. (In German and Polish)

8. Gessner, J., Wirth, M., Anders, E., Arndt, G.M., Würtz, S., Kirschbaum, F. 2003. Störaufzucht und Kaviarproduktion – wirtschaftlicher Stand und Perspektiven. Fischer und Teichwirt, 12/2003: 449-453.

9. Rosenthal, H., Gessner, J. 1993. Activity patterns of white sturgeon under aquaculture conditions. ICES Mariculture Committee, 7pp.

10. Rosenthal, H., Gessner, J. 1990. Ist die Einfuhr von A. transmontanus wirklich ohne Risiko? (Is the import of A. transmontanus without risk indeed?) Fischer und Teichwirt 90(4): 226-229

Books, Chapters of books and CD-ROMs

1. Gessner, J. 2005. 10.1 (*)Acipenser oxyrinchus oxyrinchus Mitchill, 1815. pp. 205-210. In: Petersen, B., Ellwanger, G., Bless, R., Boye, P., Schröder, E. und A. Ssymank (Bearb.): Das europäische Schutzsystem Natura 2000 Ökologie und Verbreitung von Arten der FFH-Richtlinie in Deutschland. Band 2 Schriftenreihe

2. Gessner, J., Ritterhoff, J. (Editors) 2004. Species Differentiation and Population Identification in the Sturgeons A. sturio and A. oxyrinchus. BfN-Skripten 101, 122 pp.

3. Hochleithner, M., Gessner, J., 1999. The sturgeons and paddlefishes (Acipenseriformes) of the world, their biology and aquaculture. Aqua Tech Publications, 206pp. ISBN 3-9500968-0-9

4. Hochleithner M., Gessner J., Podushka S. 2001. The Bibliography of Acipenseriformes. AquaTech Publishing, Kitzbuehel, Austria. 600 pp.

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