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Research Topics

Fish Ecology

The early piscivory of juvenile European perch was first discovered in 1999 in Lake Speldrop and revealed that in the presence of large food items (e.g. cyprinid larvae, large invertebrate larvae) a bimodal size distribution of fast-growing piscivores and slow-growing zooplanktivores can develop. The large sized piscivorous cohort can grow up to 180 mm TL in their first summer. A combination of field studies, pond experiments, mesocosm experiments and behavioural experiments in the laboratory was used to understand the role and consequences of early piscivory. Feeding, growth, behaviour, morphology, physiology, swimming performance, lipid storage and over-winter mortality of perch are some aspects that were analysed in detail, and the success depended to a large extent on the national and international co-operations (Nils Bunnefeld, Imperial College London; Don DeAngelis, University of Miami; Reiner Eckmann, University of Konstanz; Lars-Ove Eriksson, SLU Umeå; Philipp Fischer, University of Konstanz; Carin Magnhagen, SLU Umeå; Lennart Persson, University of Umeå; Gerard van der Velde, Radboud University Nijmegen). The results revealed that if the piscivorous large size-class within the YOY age cohort is able to use its growth advantages compared to their smaller conspecifics long enough, then size differences may become so large as to create a bimodal length-frequency-distribution and even intra-cohort cannibalism, which may have important and long-lasting effects on the whole fish-community

Heermann, L., Scharf, W.R., Van der Velde, G. & Borcherding, J. (2014): Does the use of alternative food resources induce cannibalism in a size-structured fish population? Ecology of Freshwater Fish 23: 129-140 (pdf)

Huss, M., Persson, L., Borcherding, J. & Heermann, L. (2013): Timing of the diet shift from zooplankton to macroinvertebrates and size at maturity determine whether normally piscivorous fish can persist in otherwise fishless lakes. Freshwater Biology 58: 1416-1424 (pdf)

Magnhagen, C., Hellström, G., Borcherding, J., Heynen, M. (2012): Boldness in two perch populations – long-term differences and the effect of predation pressure. J. Anim. Ecol. 81: 1311-1318 (pdf)

Borcherding, J., Beeck, P., DeAngelis, D. L., Scharf, W. R. (2010): Match or mismatch: the influence of phenology on size-dependent life history and divergence in population structure. Journal of Animal Ecology 79(5): 1101-1112  (pdf)

Borcherding, J., Beeck, P., DeAngelis, D. L., Scharf, W. R. (2010): Match or mismatch: the influence of phenology on size-dependent life history and divergence in population structure. Journal of Animal Ecology 79(5): 1101-1112 (pdf)

Urbatzka, R., Beeck, P., van der Velde, G. & Borcherding, J. (2008): Alternative use of food resources causes intra-cohort variation in the size distribution of young-of-the-year perch  (Perca fluviatilis). Ecology of Freshwater Fish, 17(3): 475-480  (pdf)

Borcherding J., Hermasch B., P. Murawski (2007): Field observations and laboratory experiments on growth and lipid content of young-of-the-year perch. Ecology of Freshwater Fish 16: 198-209  (pdf)
Beeck, P.; Tauber, S.; Kiel, S.; Borcherding, J. (2002). 0+ perch (Perca fluviatilis) predating on 0+ bream (Abramis brama): A case study on a eutrophic gravel pit lake at the lower Rhine, Germany. Freshwater Biology 47: 2359-2369  (pdf)

Beeck, P.; Tauber, S.; Kiel, S.; Borcherding, J. (2002): 0+ perch (Perca fluviatilis) predating on 0+ bream (Abramis brama): A case study on a eutrophic gravel pit lake at the lower Rhine, Germany. Freshwater Biology 47: 2359-2369 (pdf)




After the opening of the Rhine-Main-Danube-canal, several Ponto-Caspian gobiid fishes invaded the Lower Rhine. Starting in 1999 with the tubenose goby (Proterorhinus semilunaris), invasion succeeded with bighead goby (Ponticola kessleri) in 2006, the round goby (Neogobius melanostomus) and the monkey goby (Neogobius fluviatilis) in 2008, and was completed with the racer goby (Babka gymnotrachelus) in 2010. P. semilunaris is actually found mainly in the more lentic backwaters of the Rhine, while P. kessleri, N. melanostomus and N. fluviatilis are widespread along the whole section of the Rhine in North-Rhine-Westphalia. Actually, the latter three species even dominate the entire fish communities tremendously in increasing densities. As general species descriptions are rather similar concerning used ecological niches, the aims of our studies focus on mechanisms that separate these species with respect to the competitive exclusion principle. Diet, habitat preference, behaviour, competition and predator-prey relationships are actually studied especially with respect to differences on temporal scales (diel, seasonal), which are often underestimated considering the ecological niche of a species in competition. Our studies are in close co-operation to the Institute of Vertebrate Biology of the Academy of Sciences of the Czech Republic (Department of Fish Ecology, Pavel Jurajda, Markéta Ondračková) and with the University of Basel (Programm Mensch-Gesellschaft-Umwelt) with Patricia Holm, Irene Adrian-Kalchhauser and Philipp Hirsch.

Adrian-Kalchhauser, I., Hirsch, P.E., N'Guyen, A., Watzlawczyk, S., Gertzen, S., Borcherding, J., Burkhardt-Holm, P. (2016): The invasive bighead goby Ponticola kessleri displays small scale genetic differentiation and large scale genetic homogeneity in relation with shipping patterns. Mol. Ecol. 25: 1925-1943 (pdf)

Borcherding, J., Arndt, H., Breiden, S., Brenner, K., Heermann, L., Höfer, S., Leistenschneider, C., Lindner, J., Staas, S., Gertzen, S. (2016): Drift of fish larvae and juveniles in the Lower Rhine before and after the goby invasion. Limnologica 59: 53-62 (pdf)

Gertzen, S., Fidler, A., Kreische, F., Kwabek, L., Schwamborn V., Borcherding, J. (2016): Reproductive strategies of three invasive Gobiidae co-occurring in the Lower Rhine (Germany). Limnologica - Ecology and Management of Inland Waters 56, 39-48 (pdf)

Ondracková, M., Valová, Z., Hudcová, I., Michálková, V.,  Andrea Simková, A., Borcherding, J., Jurajda, P. (2015): Temporal effects on host-parasite associations in four naturalized goby species living in sympatry. Hydrobiologia 746: 233-243 (link)

Borcherding, J., Dolina, M., Heermann, L., Knutzen, P., Krüger, S., Matern, S., van Treeck, R. & Gertzen, S. (2013): Feeding and niche differentiation in three invasive gobies in the Lower Rhine, Germany. Limnologica 43: 49-58 (pdf)

Borcherding, J., Staas, S., Krüger, S., Ondračková, M., Šlapanský, L., Jurajda, P. (2011): Non-native Gobiid species in the lower River Rhine (Germany): recent range extensions and densities. Journal of Applied Ichthyology 27: 1-3 (pdf)



Starting in the 19th century, major dam building activities for hydro-electric power began to disconnect the different habitats within the River Rhine system. During the last few centuries, connections of the freshwater reaches of the River Rhine and its estuaries in the Netherlands were blocked by massive dams and locks, and the remaining habitats have been severely impacted by humans, which resulted in a massive decline of all anadromous fish species in the River Rhine. One anadromous species, the North Sea houting, Coregonus oxyrinchus, has been considered extinct in the River Rhine since the 1940s. Therefore, it was decided to reintroduce houting in the German section of the River Rhine. This reintroduction programme was managed and monitored by us since 2000, and we studied the main bottlenecks of the houting life-cycle under the anthropogenically modified environmental conditions. First results revealed that stocked juveniles start directly to feed in the new environment and migrated rapidly downstream. Based on 88Sr:44Ca ratio of scales from houting caught in Lake IJsselmeer, we could show different migration patterns for houting and provided evidence that this species is sometimes able to pass the migratory barriers between the Wadden Sea and Lake IJsselmeer, and does not need to migrate to sea to reach maturity. Finally, a mark–recapture experiment was conducted in 2006, in which all houting embryos were stained with Alizarin before being stocked into the Lower Rhine. The results suggest that the majority of YOY houting in 2006 originated from natural reproduction, indicating the presence of a self-sustaining population, and, thus that the re-introduction programme of North Sea houting in the Rhine system can be considered a success. Actually we are investigating the appearance of newly hatched larvae and perform genetic analyses of different parts of the North Sea houting population in the Rhine system. As in other projects, the reintroduction programme with houting also depends on close co-operations with national and international partners (e.g. Andre Breukelaar, Rijkswaterstaat Waterdienst Lelystad; Erwin Winter, IMARES, Wageningen).

Borcherding, J., Breukelaar, A.W., Winter, H.V., König, U. (2014): Spawning migration and larval drift of anadromous North Sea houting (Coregonus oxyrinchus) in the River IJssel, the Netherlands. Ecology of Freshwater Fish 23: 161-170 (pdf)

Dierking, J., Phelps, L., Praebel, K., Ramm, G., Prigge, E., Borcherding, J., Brunke, M. & Eizaguirre, C. (2014): Anthropogenic hybridization between endangered migratory and commercially harvested stationary whitefish taxa (Coregonus spp.). Evolutionary Applications 7: 1068-1083 (pdf)

Borcherding, J., Heynen, M., Jäger-Kleinicke, T., Winter, H.V., Eckmann, R. (2010): Re-establishment of the North Sea houting in the River Rhine. Fisheries Management and Ecology 17: 291-293 (pdf)

Borcherding, J., Pickhardt, C., Winter, H.V., Becker, J.S. (2008): Migration history of North Sea hounting (Corogonus oxyrinchus L.) caught in Lake Ijsselmeer (The Netherlands) inferred from scale transects of 88Sr:44Ca ratios. Aquatic Sciences 70: 47-56 (pdf)

Borcherding, J., Scharbert, A., Urbatzka, R. (2006). Timing of downstream migration and food uptake of juvenile North Sea houting stocked in the Lower Rhine and the Lippe (Germany). Journal of Fish Biology 68:1271-1286 (pdf)



Starting in the late 1980s under the supervision of Dietrich Neumann, the fish community of the River Rhine and adjacent backwaters was studied in detail at the ecological field station in Grietherbusch. First, the fish communities of the river banks, the gavel pit lakes which are permanently connected to the river as well as the last existing oxbows were in the focus. They not only revealed how the structural diversity of the banks affects the development of the juvenile fish community, but also established new insights of potamodromous lateral migrations in the floodplain of a large river. These studies were then added by the analysis of the influence of inundation frequency on the fish communities of permanently connected waters and those with semi-permanent or ephemeral hydrological character. We have now clear indications on the significance of hydrological transversal floodplain gradients, for providing diverse communities and population maintenance of different life-history strategies under a variety of hydrograph scenarios. Recently, our research was combined with nature conservation and focuses now on the fish communities of some backwaters that will be reconstructed in the “EU LIFE+ Project for the Re-establishment of a side channel at the Lower Rhine near Wesel (North Rhine-Westphalia) ”.

Scharbert, A., Borcherding, J. (2013): Relationships of hydrology and life-history strategies on the spatio-temporal habitat utilisation of fish in European temperate river floodplains. Ecological Indicators 29: 348-360 (pdf)

Borcherding, J. & Staas, S. (2008): Local riverine fish communities as promotors for habitat restoration in the floodplain area of the Lower Rhine. 4th World Fisheries Congress, Vancouver, Canada, 49: 835-843 (pdf)

Breteler, J.K., Vriese, T., Borcherding, J., Breukelaar, A., Jorgensen, L., Staas, S., de Laak, G. & Ingendahl, D. (2007): Assessment of population size and migration routes of silver eel in the River Rhine based on a 2-year combined mark-recapture and telemetry study. ICES Journal of Marine Science, 64 (7): 1450-1456 (pdf)

Heermann, L. & Borcherding, J. (2006): Winter short-distance migration of juvenile fish between two floodplain water bodies of the Lower River Rhine. Ecology of Freshwater Fish 15: 161-168 (pdf)

Borcherding, J., Bauerfeld, M., Hintzen,D., Neumann, D. (2002):  Lateral migrations of fishes between floodplain lakes and their drainage channels at the Lower Rhine: diel and seasonal aspects. Journal of Fish Biology 61: 1154-1170 (pdf)

Molls, F. (1999):  New insights into the migration and habitat use by bream and white bream in the floodplain of the River Rhine. Journal of Fish Biology 55: 1187-1200 (pdf)



Since 2015, Katja Heubel and Karen de Jong joined the Ecological Research Station in Rees-Grietherbusch adding fundamental background in animal evolutionary ecology, including aquatic ecology, behavioural ecology and biodiversity. Expertise in experimental approaches and knowledge in theoretical evolutionary ecology. Research focus on eco-evolutionary links in population ecology, sexual selection, life-history evolution, context-dependent reproductive decisions, behavioural adaptations to changing ecological contexts, effect of ambient noise on sexual selection, and dynamics of sexual-asexual coexistence.


Bleeker K, de Jong K, van Kessel N, Hinde CA, Nagelkerke LAJ (2017): Evidence for ontogenetically and morphologically distinct alternative reproductive tactics in the invasive Round Goby Neogobius melanostomus. PLOS ONE 12(4): e0174828. doi: 10.1371/journal.pone.0174828 (pdf)

de Jong K, Schulte G, Heubel KU (2017): The noise egg: A cheap and simple device to produce low-frequency underwater noise for laboratory and field experiments. Methods in Ecology and Evolution 8:268–274. DOI: 10.1111/2041-210X.12653 (pdf)

Blom EL, Mück I, Heubel K, and Svensson O (2016): Acoustic and visual courtship traits in two sympatric marine Gobiidae species - Pomatoschistus microps and Pomatoschistus minutus. Environmental Biology of Fishes 99(12): 999-1007 (pdf)

de Jong, K., Amorim, M. C. P., Fonseca, P. J., Klein, A. and & Heubel, K. U. (2016): Noise affects acoustic courtship behavior similarly in two species of gobies. Proceedings of Meetings on Acoustics 27: 010018, doi: 10.1121/2.0000272 (pdf)

Vallon M, Anthes N, Heubel KU (2016): Water mold infection but not paternity induces selective filial cannibalism in a goby. Ecology and Evolution 6(20):7221-7229 (pdf)

Vallon M, Grom C, Kalb N, Sprenger N, Anthes N, Lindström K, Heubel KU (2016): You eat what you are: Personality-dependent filial cannibalism in a fish with paternal care. Ecology and Evolution 6(5): 1340-1352 (pdf)