Stephanie Kalberer


I am interested in the interaction between ecological and evolutionary processes in changing environments. Previous studies have shown that environmental changes and climatic variations influence the dynamics of the populations of plants, invertebrates and vertebrates and also the dynamic of heritable phenotypic traits. Such results indicate that ecological and evolutionary responses can occur on the same timescales and species may be able to adapt to environmental change within evolutionary short time periods. Significant changes in the response to environmental change with trophic level have been documented. However, so far, the effects at higher trophic levels are not well understood but a deeper knowledge of how abiotic change and variability affect Galápagos sea lions is vital for maintaining the ecosystems’ balance. In my PhD I am thus looking at how variation in environmental productivity affects the energetics of reproduction in Galápagos sea lions (Zalophus wollebaeki), and how this may lead to variation in fertility rates among females and years, which in turn drive population demography and population ecology.

Previous Research and Other Interests

During my masters degree at University of Zurich, a particular attention has been drawn on molecular ecology of marine mammals by investigating the relatedness pattern in male bottlenose dolphin (Tursiops sp.) alliances in Shark Bay, Western Australia. This project included a significant proportion of field work in Western Australia like collecting behavioural data, conducting group surveys, doing photo-identification as well as lab work like generating microsatellite data, doing molecular sexing and mtDNA analyses.

My free time I love to spend hiking in the mountains, traveling the world, discovering different kind of music and getting lost in good books.

Supervisors and collaborators

Prof. Oliver Krüger, Bielefeld University, Germany
Prof. Dr. Fritz Trillmich, University of Bielefeld
Dr Joe Hoffman, University of Bielefeld
Galápagos National Park Service
Charles Darwin Research Station

  • 2015–Present: PhD Student – University of Bielefeld
  • August 2012: Integral projection modelling – Swiss Federal Institute for Forest, Snow and Landscape Research
  • 2012: MSc in Anthropology, University of Zurich
  • December 2011: Introduction to distance sampling – University of St. Andrews
  • Summer 2010: Summer School Cambridge – University of Cambridge
  • 2010: BSc in Biology, University of Zurich
  • Summer 2007: Introduction to Marine Mammology – Marine mammal research station, Mériscope, Québec
Professional Experience
  • 2010-2015: Research Assistant – Redbiotec AG, Switzerland
  • 2013-2014: Research Associate – Evolutionary Genetics Group, University of Zurich
  • 2012-2013: Laboratory Technician and Teaching – Evolutionary Genetics Group, University of Zurich
  • Winter 2011: Internship at Marine Science Centre – University of Rostock
  • Spring 2010: Field assistance in the Kalahari Meerkat Project – University of Zurich & University of Cambridge
  • 2009-2010: Statistical consulting – Physiological Institute, University of Zurich
  • Summer 2008: Research assistance – Marine mammal research station Mériscope, Québec


  • Kalberer S., Meise K., Piedrahita P., Páez-Rosas D., Trillmich F., Krüger O.. Apex predator survival in a fluctuating, tropical environment: the case of the Galapagos sea lion (under review in Marine Mammal Science).
  • Gerber L., Connor R. C., Wittwer S., Allen S. J., Bizzozzero M., Friedman W.R., Kalberer S., et al.. Multi-level cooperation in male bottlenose dolphins is predicted by long-term investment in social bonds, not kinship (under review in Nature Communications).
  • Kalberer S., DeRango E., Trillmich F., Krüger O.. Evolution of age at primiparity in pinnipeds in the absence of the quality-quantity trade-off in reproduction (under review in Ecology and Evolution).
  • Kalberer S., Meise K., Trillmich F., Krüger O. (2018). Reproductive performance of a tropical apex predator in an unpredictable habitat. Behavioral Ecology and Sociobiology. Vol. 72, No. 108.
  • Trillmich F., Meise K., Kalberer S., Mueller B., Piedrahita P., Pörschmann U., Wolf J. B. W., Krüger O. (2016). On the Challenge of Interpreting Census Data: Insights from a Study of an Endangered Pinniped. PLoS ONE. Vol. 11, No. 5.
  • Fedder C., Beck-Schimmer B, Aguirre J, Hasler M, Roth-Z’graggen B, Urner M, Kalberer S, Schlicker A, Votta-Velis G, Bonvini JM, Graetz K, Borgeat A. (2010). In vitro exposure of human fibroblasts to local anaesthetics impairs cell growth. Clinical & Experimental Immunology. Vol. 162, No. 2: 280-288

Conference contributions

  • Kalberer S., Meise K., Trillmich F., Krüger O. (2017), Silver Spoon for a Golden Future? Reproductive Scheduling in the Galapagos Sea Lion. Presentation at the 22nd Biennial Marine Mammal Conference, Halifax, Nova Scotia.
  • Kalberer S., Meise K., Trillmich F., Krüger O. (2017), Unpredictable Life History in an Unpredictable Habitat? Reproductive Scheduling in the Galapagos Sea Lion. Presentation at the Deutsche Zoologische Gesellschafts Tagung, Bielefeld, Germany
  • Kalberer S., Trillmich F., Meise K., Mueller B., Piedrahita P., Pörschmann U., Wolf J. B. W., Krüger O. (2016), How accurate are Census Data? Estimating colony size of Galapagos Sea Lions. Poster presented at the Deutsche Zoologische Gesellschafts Tagung, Kiel, Germany.
  • Kalberer S., Kopps A., Allen S., Krützen M. (2012), Social structure and relatedness patterns in male bottlenose dolphins of Western Shark Bay, Western Australia. Poster presented at the European Cetacean Society Conference, Galway, Ireland.
  • Postma, E. and Kalberer S. (2010), What’s in a name? Inferring inbreeding and population structure in modern-day Switzerland. Poster presented at the Biology 10 Conference, Neuchâtel, Switzerland.

Contact Details

Department of Animal Behaviour
Bielefeld University
Postfach 100131
33501 Bielefeld

email: stephanie.kalberer[at]

I am funded by: