Patterns, determinants and ecological consequences of individualized landscapes of fear

• Applicant: Professorin Dr. Melanie Dammhahn
• Subject Area: Sensory and Behavioural Biology ; Ecology and Biodiversity of Animals and Ecosystems, Organismic Interactions
• Term: since 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 387227692

Natural selection via predation is a fundamental evolutionary force. Ultimately, the intrinsic risk of falling prey to a predator determines individual fitness. Moreover, the mere presence of a predator can lead to changes in prey morphology, physiology, life-history and behaviour. Perceived predation risk by prey determines the type and strength of these indirect predation effects, which involve energetic trade-offs and, thus, affect prey fitness indirectly. Today indirect predation effects are recognized as an important aspect of predator-prey interactions. Perceived predation risk varies in space and time creating landscapes of fear. Hitherto, landscapes of fear have been studied as species-specific layers, assuming that each individual of a species perceives the same risk. In the first phase of the project, we experimentally demonstrated among-individual differences in perceived predation risk, creating individual landscapes of fear. By experimentally manipulating spatial and temporal predation risk in artificial landscapes for bank voles (Myodes glareolus), we showed that individual landscapes of fear exist, developed tools to quantify and compare them effectively, and tested whether among-individual differences in perceived predation risk can be predicted by personality differences. By developing a new concept and method – diversity at giving-up density – and by closely interlinking experimental and spatially-explicit individual-based modelling approaches we started unravelling the consequences of individualized landscapes of risk on ecological interactions within and between species. In the second phase of the project, we focus on three central objectives that derive from newly emerging questions of our previous work. First, we aim to illuminate whether and how individuals mitigate the costs of fear by testing individual (co)variation between foraging activity under perceived predation risk and metabolism during resting. Second, we aim to illuminate non-invasively and in real-time via high-resolution thermography whether among-individual differences in perceived predation risk are related to among-individual variation along the proactive-reactive personality continuum. Third, we will test whether variation in risk-taking can be explained by variation in future fitness expectations and whether and how this relationship is mediated by body condition. Finally, we will focus on one potential ecological consequence of among-individual variation in landscape of fear and test the effects on biodiversity at the resource level.

• DFG Programme: Research Grants