Thünen PhD student Sabrina Duncan visited the Ludwig-Maximilians University of Munich (LMU) to present research based on her Master's thesis and to accept the ''Research Prize for Excellent Students'' for her project titled ''Zooplankton biomass and stoichiometry in Bavarian pre-alpine lakes and their influence on whitefish (Coregonus sp.) growth.''
During recent decades the amount of nutrients such as phosphorus and nitrogen have changed in some Bavarian lake and nutrients such as phosphorus have been reduced in order to bring lakes back to their natural oligotrophic state. Fisherman have reported that the size of whitefish has been very variable in the different Bavarian lakes and the aim of this project between the University of Munich, the Bayerisches Landesamt für Umwelt, and the Bayerische Landesanstalt für Landwirtschaft, was to gain baseline data on the nutrient levels of eleven different lakes and to determine if this may influence whitefish size and growth.
During her Master’s, Sabrina studied the effects of nutrients and zooplankton community composition on whitefish diet and size. She worked together with the University of Munich and local fisherman in Bavaria to collect zooplankton samples and whitefish in order to compare zooplankton communities in lakes that differed in nutrients and human activity, as well as to compare the stomach contents of fish, and to determine if diet had an impact on fish size. After finding differences in zooplankton composition as well as the diet and size of fish between the lakes, she took part in the ''Lehre@lmu'' program that funds student proposals, and compared the quality of important zooplankton groups in each of the lakes in order to see if not only community composition but also prey quality influenced whitefish size. Results showed that the quality of zooplankton, measured by biomass and chemical composition, in commonly consumed zooplankton such as Daphnia longispina, differed in each of the lakes, and found trends showing increased zooplankton quality yielded increased whitefish size. Each year ''Lehre@lmu'' reports are collected from all faculties of the university and 12 prizes are given out to each of the winners at the annual ''Lehre@lmu'' ceremony.
If you have questions, feel free to contact Sabrina Duncan.