Biological Invasions

Global trading and traveling cause the transportation of organisms to regions in which they did not occur before. Oftentimes, these organisms manage to establish and spread in these new ranges. These processes are called biological invasions.

Together with Jonathan Jeschke and many colleagues, I analyzed literature to find out which major hypotheses in invasion ecology are supported by empirical evidence. The results are published in a book [link], and a visualized, interactive summary can be found at hi-knowledge.org/invasion-biology.

Besides on mechanisms of biological invasions, I have been working on the evolutionary ecology of invasive plants. Together with Andrew Latimer and others, I have studied Erodium cicutarium, a plant native to Europe and invasive e.g. in North and South America. Very interesting to me is also the ethical question how to deal with these species.

Projects

Related Publications

Full list of publications here.

Related Publications

Books:

Jeschke, J. M. & Heger, T. (eds)(2018): Invasion Biology – Hypotheses and Evidence; CABI Publishing, Wallingford, UK, 177 pp. Accompanying web page: hi-knowledge.org/invasion-biology.

Heger, T. (2004): Zur Vorhersagbarkeit biologischer Invasionen. Entwicklung und Anwendung eines Modells zur Analyse der Invasion gebietsfremder Pflanzen. – Schriftenreihen Neobiota Band 4, Berlin, 197 S. [link to pdf]

Essays:

Heger, T. (2019). Invasive Species – Boon or Bane? Topos 108: 90-93.

Heger, T. (2019). Lässt sich vorhersagen, ob eine Art invasiv wird? – Krumm, F. & Vítková, L. (eds.). Eingeführte Baumarten in europäischen Wäldern: Chancen und Herausforderungen. European Forest Institute: 80-87.

Heger, T. (2018): Menschen, Pflanzen, Aversionen? Gebietsfremde Arten und neuartige Ökosysteme, Nodium – Zeitschrift des Alumni-Clubs Landschaft der TU München 10: 64-67.

Heger, T. (2016) Can we predict whether a species will become invasive? – Krumm, F. & Vítková, L. (eds.). Introduced tree species in European forests: opportunities and challenges. European Forest Institute: 78-84. 

Other Publications:

Eilers, E.J. & Heger, T. (2019) Past competition affects offspring foliar terpenoid concentrations, seed traits, and fitness in the invasive forb Erodium cicutarium (Geraniaceae). Frontiers in Ecology and Evolution 7. DOI: 10.3389/fevo.2019.00392. Open access

Heger, T. (ed.)(2019): Special Issue ‘Invasive Plants’. Plants.

Latimer, A. M., Jacobs, B. S., Gianoli, E., Heger, T. & Salgado-Luarte, C. (2019). Parallel functional differentiation of an invasive annual plant on two continents. AoB Plants 11: plz010. DOI: 10.1093/aobpla/plz010. Open access

Rabitsch, W., Heger, T., Jeschke, J., Saul, W.-C. & Nehring, S. (2018): Analyse und Priorisierung der Pfade nicht vorsätzlicher Einbringung und Ausbreitung invasiver gebietsfremder Arten in Deutschland gemäß Verordnung (EU) Nr. 1143/2014 - Analysis and prioritisation of pathways of unintentional introduction and spread of invasive alien species in Germany in accordance with Regulation (EU) No 1143/2014. - BfN-Skripten 490. Bundesamt für Naturschutz, Bonn - Bad Godesberg, 103 S.

Rabitsch, W., Heger, T., Jeschke, J. M. & Saul, W.-C. (2018) Priorisierung der Pfade unabsichtlicher Einbringung und Ausbreitung invasiver gebietsfremder Arten in Deutschland. Natur und Landschaft 9/10: 416-422. DOI: 10.17433/9.2018.50153617.416-422

Yannelli, F. A., Karrer, G., Hall, R., Kollmann, J. & Heger, T. (2018) Seed density is more effective than multi-trait limiting similarity in controlling grassland resistance against plant invasions in mesocosms. Applied Vegetation Science 21: 411-418. DOI: 10.1111/avsc.12373

Heger, T., Nikles, G. & Jacobs, B. (2018) Differentiation in native as well as introduced ranges: germination reflects mean and variance in cover of surrounding vegetation. AoB Plants 10: ply009. DOI: 10.1093/aobpla/ply009. Open access

Heger, T. (2016) Light availability experienced in the field affects ability of following generations to respond to shading in an annual grassland plant. Journal of Ecology 104: 1432–1440. DOI: 10.1111/1365-2745.12607

Heger, T., Jacobs, B. S., Latimer, A. M., Kollmann, J. & Rice, K. J. (2014): Does experience with competition matter? Effects of source competitive environment on mean and plastic trait expression in Erodium cicutarium. Perspectives in Plant Ecology Evolution and Systematics 16: 236-246. DOI: 10.1016/j.ppees.2014.06.002

Heger, T., Saul, W.-C. & Trepl, L. (2013): What biological invasions 'are' is a matter of perspective. Journal for Nature Conservation 21: 93-96. DOI: 10.1016/j.jnc.2012.11.002

Jeschke, J.M., Gómez Aparicio, L., Haider, S., Heger, T., Lortie, C.J., Pyšek, P. & D.L. Strayer (2012a): Taxonomic bias and lack of cross-taxonomic studies in invasion biology. Frontiers in Ecology and the Environment 10: 349-350. DOI: 10.1890/12.WB.016

Jeschke, J.M., Gómez Aparicio, L., Haider, S., Heger, T., Lortie, C.J., Pyšek, P. & D.L. Strayer (2012b): Support for major hypotheses in invasion biology is uneven and declining. NeoBiota 14: 1-20. DOI: 10.3897/neobiota.14.3435

Heger, T. & L. Trepl (2003): Predicting biological invasions. Biological Invasions 5: 313–321. DOI: 10.1023/B:BINV.0000005568.44154.12