Denise Disacke


The invasive amphibian parasite Batrachochytrium dendrobatidis (Bd) in Vienna: Biomonitoring using environmental DNA

MSc Student
Advisor: Günter Gollmann

Unit for Theoretical Biology, Department of Evolutionary Biology
University of Vienna


There are many reasons for the worldwide amphibian decline since the 1950s such as loss of natural habitats, climate change or environmental pollution. One of the most devastating causes is the pathogenic, aquatic zoosporic fungus Batrachochytrium dendrobatidis (Bd),which is responsible for the global disease chytridiomycosis in amphibians. In Austria infected specimens were detected in all nine provinces. For example, in Vienna the fungus was detected in five of seven sampled sites in the year 2011. There was still no mass mortality provoked by Bd in Vienna, but the quantity of Bd positive tested animals is alarming. Further observation of the fungus distribution is necessary. This study reviewed the applicability of the Environmental DNA method for a monitoring of Bd and gave an actual infection situation in Vienna. Water samples were collected from ten water bodies in Vienna over a period of two months. DNA of the water samples was extracted, purified and analyzed by Real Time PCR methods. Additionally, skin swabs were taken from amphibians around or in the tested ponds and Bd positive specimens from the Vienna Zoo were included as positive control. All the skin swabs and all water samples were tested Bd negative. Fortunately, there are a few fungus- limiting factors such as, for example, a temperature over 25°C, or the amphibian skin microbiome, or the fact that some planktonic predators feed on Bd. The load with the Chytrid-fungus on amphibian species varies from time to time, so it is very important to have an overview of its spread regularly.