Thomas Naef

Applied Zoology and Nature Conservation

Soldmannstr. 14
17489 Greifswald

thomas.naef(at)stud.uni-greifswald(dot)de
thomasnaef.research(at)gmail(dot)com

ResearchGate

Research Interests

Range expansion and dispersal in lesser horseshoe bats

I am widely interested in the field of biological responses to climate change and other anthropogenic influences. For my PhD thesis in Greifswald, I am particularly focusing on the lesser horseshoe bat (Rhinolophus hipposideros) and its response to climate change. Due to habitat fragmentation, intensified agriculture and the use of harmful insecticides like DDT since the mid-20th century, the population size of the lesser horseshoe bat strongly declined in Germany and many other European countries. During the last decade, probably also through the help of conservational organizations, the situation for those bats improved in Germany and population size in Thuringia even increased again. Recently, the lesser horseshoe bat is still recolonizing former lost habitats and we can observe an ongoing, but slow dispersal leading to range expansion northward in Germany, which was also predicted in different climate change models. Nevertheless, Rhinolophus hipposideros is still an endangered species in Germany and much has to be learned about its responses to changing environments to effectively predict and secure the future of this species.
Therefore, I will get further insights into the mechanisms of this dispersal and range expansion by answering the following questions: 1) How do new colonies form? 2) Are there differences between small newly formed and old isolated small colonies?  The lesser horseshoe bat is endangered and protected in Germany, I therefore work with a non-invasive genetic Capture-Mark-Recapture approach to avoid unnecessary disturbance. I use DNA extracted from bat droppings to reconstruct individual genotypes on which I base population parameter estimates and answer the aforementioned questions. Additionally, for question 1, I will establish acoustic sexing, directionality and potential age based on echolocation calls to enlarge sample size and refine population parameter estimates in order to get even more detailed insights into the life of this rare and cryptic bat.

To increase efficient resource allocation in non-invasive sampling, I also investigate and quantify abiotic factors influencing the quality of the so retrieved genotypes.

Animal coloration and scientific photography

Due to my past work in animal coloration during my master on Lake Tanganyikan cichlids at the University of Basel, my interests in in the broad field of animal body coloration and patterning grew and I therefore gained valuable experience in scientific digital photography and coloration measurement.

Links

GRK 2010 Biological RESPONSEs to Novel and Changing Envrironments 

RESPONSE Project B6

Publications

  • Naef, T., Besnard, A.-L., Lehnen, L., Petit, E. J., van Schaik, J., & Puechmaille, S. J. (2023). How to quantify factors degrading DNA in the environment and predict degradation for effective sampling design. Environmental DNA, 5, 403– 416. https://doi.org/10.1002/edn3.414