Dr. René Gergs

Research Interests

My main research area is the ecology of freshwater systems (Limnology) with a special focus on the impact of invasive species on macroinvertebrate communities and the food web structure. Additionally I am also interested in the phylogeography of invasive invertebrates and their limits in range extension. In doing so I use a wide range of methods to consider different point of views, including:

• genetic analyses
• stable isotope analyses (see SI lab)
• micro- and mesososm experiments
• field surveys

Academic History

• Research Assistant (since May 2010):
  Institute of Environmental Science, University of Koblenz-Landau

• Post doc (2009 until 2010)
  Research fellowship at the University of Konstanz

• PhD (2009):
  "Dreissena polymorpha in Lake Constance: An example of a keystone engineer?"
  At the Limnological Institute of the Universität of Konstanz

• Diploma (M. Sc.) (2004):
  "Quantitative analysis of the seasonal development of grazers and periphyton in a small midland stream"
  At the Limnological River Station Schlitz of the Max-Planck-Institute for Limnology

• Study of Biology (1998 until 2004):
  University of Freiburg

Teaching

• Limnoecology

• Aquatic-terrestrial ecology

• Ornithology

• Indicator organisms

Click here to download pdfs from single lectures.

Current Research Projects

• Invasive amphipods - Trophic interactions between native and invasive amphipod species in aquatic systems. (DFG-project; PhD thesis Meike Koester) more Info

• Genetic analyses of populations of brown trout [Salmo trutta (L.)] in the Palatinate Forest. (PhD thesis Thomas Schmidt) more Info

• Studies on the reestablishment of populations of the anadromous alice shad (Alosa alosa) in River Rhine. (PhD thesis Matthias Hundt) more Info

• Niche partitioning of the invasive amphipod Dikerogammarus villosus and the indigenous Gammarus roeselii.

• Conservation program for threatend freshwater fish species, crayfish and mussels (more Info)

Former Research Projects

• Zebra mussel (Dreissena polymorpha) biodeposition based food web - Implication of the filtration activity of the mussel on the benthic macroinvertebrate community and food web structure. more Info

Offered studies (Case study, diploma or master thesis)

• Comparison of the functional response and size-dependent feeding rates of the invasive amphipod Dikerogammarus villosus and the indigenous Gammarus roeselii.

• Changes in genetic diversity of a native amphipod (Gammarus roeselii) as consequence of an invasion process - analyses of a longterm dataset.

• Genetic and autecological studies on juvenile European weather loach (Misgurnus fossilis) for protection purposes.

• Substance-specific analyses of food quality effects in Daphnia (in cooperation with the Limnological Institute of the University of Konstanz).

• Impact of invertebrate invasive predators on the subsidisation of riparian arthropods.

If you are interested in working on one the suggested theses, contact me via email or come around to my office. The listed projects are examples for a study under my supervision. Based on own ideas, we also can develop new projects.

Supervised studies

Current studies

• Genetische Charakterisierung verschiedener Bachforellenpopulationen, Salmo trutta (L.), des Pfälzerwalds (Diploma thesis Kathrin Metzner)

• Food quality related growth of the amphipod Gammarus roeselii (Diploma thesis Nicole Steinberger)

Former studies

• Development of group-specific primer for genetic gut content analyses (Diploma thesis Meike Koester)

• Impact of temperature and invertebrate predation on the population of Limnomysis benedeni in Lake Constance. (Diploma thesis Almut J. Hanselmann)

• Ammonium- and pH- tolerance of two amphipod species in Lake Constance. (Bachelor thesis Lena Schlag)

Recent Publications

for a paper request please contact Dr. René Gergs

Peer-reviewed articles

2011

2010

2009

2008

Other publications

2008

Awards

Young scientist award of the German Limnological Society (DGL) 2011

Conference contributions

• Gergs. R. (2011). Interspezifische Auswirkungen von invasiven Invertebraten: Verdrängung, Koexistenz oder positiver Einfluss? DGL–Tagung 2011 (Freising, Germany), invited talk, Young Scientist Award.

• Gergs, R. & Schulz, R. (2011). System-übergreifende trophische Effekte – Beeinflusst Dikerogammarus villosus terrestrische Nahrungsnetze? DGL–Tagung 2011 (Freising, Germany), poster presentation

• Metzner, K., Gergs, R. & Schmidt, T. (2011). Genetische Charakterisierung verschiedener Bachforellenpopulationen, Salmo trutta (L.), des Pfälzerwalds. DGL–Tagung 2011 (Freising, Germany), oral presentation

• Heimann, W., Futterer, D., Schulz, H., Gergs, R. & Schulz, R. (2011). Der Einfluss von Uferstrukturen auf die Erfassung der Fischfauna mittels Elektrofischerei. DGL–Tagung 2011 (Freising, Germany), oral presentation

• Gergs, R., Schlag, L. & Rothhaupt, K.-O. (2010). Koexistenz zwischen den Amphipoden Gammarus roeselii und Dikerogammarus villosus im Bodensee – Ammoniak als Mediator? DGL–Tagung 2010 (Bayreuth, Germany), oral presentation

• Basen, T., Gergs, R. & Martin-Creuzburg, D. (2010). Benthisch-pelagische Kopplung durch die invasive Süßwassermuschel Corbicula fluminea. DGL–Tagung 2010 (Bayreuth, Germany), oral presentation

• Gergs, R. & Rothhaupt, K.-O. (2010). Zebra mussels couple the pelagic primary production to the benthic food web. Symposium “The Role of Littoral Processes in Lake Ecology” (Konstanz, Germany), oral presentation

• Hanselmann, A.J., Gergs, R. & Rothhaupt, K.-O. (2010). Life-cycle shifts of Limnomysis benedeni – caused by fish?. Symposium “The Role of Littoral Processes in Lake Ecology” (Konstanz, Germany), poster presentation

• Gergs, R. & Rothhaupt, K.-O. (2009). Dreissena polymorpha als Keystone Art für einheimische und invasive Amphipoden im benthische Nahrungsnetz. DGL–Tagung 2009 (Oldenburg, Germany), oral presentation

• Rothhaupt, K.-O., Gergs, R., Werner, S., Hesselschwerdt, J. & Mörtl, M. (2009). Invasive benthic invertebrates in Lake Constance - Impacts on littoral communities. 2nd European Large Lakes Syposium, (Norrtälje, Sweden), oral presentation

• Gergs, R., Hanselmann, A.J., Aßmann, C. & Rothhaupt, K.-O. (2008). Syn- und autökologische Untersuchungen an Limnomysis benedeni im Bodensee. DGL–Tagung 2008 (Konstanz, Germany), oral presentation

• Hanselmann, A.J., Gergs, R. & Rothhaupt, K.-O. (2008). Saisonale Änderungen der Life-Cycle-Parameter von Limnomysis benedeni im Bodensee. DGL–Tagung 2008 (Konstanz, Germany), oral presentation

• Schlag, L., Gergs, R. & Rothhaupt, K.-O. (2008). Ammonium und pH-Toleranz zweier Amphipodenarten im Bodensee. DGL–Tagung 2008 (Konstanz, Germany), oral presentation

• Gergs, R. & Rothhaupt, K.-O. (2008). Biodeposition by Dreissena polymorpha: A food source for native and invasive amphipod species. ASLO Summer Meeting 2008 (St. Johns, Newfoundland), oral presentation

• Gergs, R. & Rothhaupt, K.-O. (2007). Trophische Interaktionen zwischen Zebramuscheln und einheimischen bzw. invasiven Amphipoden im Litoral des Bodensees. DGL–Tagung 2007 (Münster, Germany), oral presentation

• Gergs, R., Hesselschwerdt, J. & Rothhaupt, K.-O. (2006). Stabile Isotopen - Signatur und Verteilung einheimischer und invasiver Gammariden in verschiedenen Habitattypen des Bodensees. DGL–Tagung 2006 (Dresden, Germany), oral presentation

• Hesselschwerdt, J., Gergs, R. & Wantzen, K.M. (2006). Mögliche Refugialhabitatevon Gammarus roeselii nach der Invasion  durch den räuberischen Neozoen Dikerogammarus villosus im Bodensee. DGL–Tagung 2006 (Dresden, Germany), oral presentation

• Gergs, R. & Rothhaupt, K.-O. (2006). Quantification and characterisation of biodeposition of the zebramussel (Dreissena polymorpha): A field study and a laboratory approach. Annual NABS Meeting 2006 (Anchorage, Alaska), poster presentation

• Gergs, R. & Rothhaupt, K.-O. (2005). Quantifizierung der Biodeposition von Dreissena polymorpha mittels modifizierter Sedimentfallen. DGL–Tagung 2005 (Karlsruhe, Germany), poster presentation

• Gergs, R. & Becker, G. (2004). Quantitative Analyse der saisonalen Entwicklung von Weidegängern & Periphyton im Längsverlauf eines Mittelgebirgsbaches. DGL–Tagung 2004 (Potsdam, Germany), oral presentation

Contact Details

Dr. rer. nat. René Gergs
Institute of Environmental Science
University of Koblenz-Landau
Fortstrasse 7
Room I 3.28
76829 Landau
Germany