Scientist

Faculty of Biology
Aquatic Ecology
Universitätsstrasse 5
D-45141 Essen
Germany

Room S05T03B23
Phone: +49.201.18.34695
Fax: +49.201.18.32179
maya.kays@uni-due.de

PhD thesis: Parasite-mediated responses of aquatic hosts to environmental stress: experimental and field-based insights from recovering stream ecosystems

Parasites can affect physiology and behaviour of their hosts, thereby influencing population dynamics. This effect can be further modulated by environmental stress. However, the combined effects of parasite infections and abiotic stressors such as salinity and temperature on aquatic hosts have been rarely studied in the context of ecosystem recovery.

This doctoral project aims to investigate how parasite infections influence host tolerance and dispersal under environmental stress and how parasite communities recolonise habitats in recovering ecosystems. To this end, laboratory experiments will be conducted using parasitized and unparasitized macroinvertebrates (e.g., gammarids) to assess physiological and behavioural responses to salinity and temperature. Endpoints will include mortality, respiration rates, biomarker response, and activity levels.

Furthermore, we will compare the dispersal potential and energy reserves of infected and uninfected aquatic insects with terrestrial adult stages, in the field and in a semi-natural field flume system simulating recovery after drought. To assess re-establishment of fish parasite communities in recovering ecosystems, we will investigate the developing fish parasite communities of the recently restored Emscher river system.

By combining experimental with field data, this project will contribute to understanding the role of parasitism in shaping community responses during and after ecological restoration.