The Cascading Effects of Predation Risk in the Wild: How the Gut Microbiome Mediates the Adaptive Fear Response
Advisor: Michael Sheriff
Committee Members: Professor Mark Silby, Professor Genny Kozak, and Professor Vanni Bucci (UMass Chan Medical).
Abstract: Predators influence prey not only by killing them, but also by altering how they behave and function in the face of chronic risk. In this dissertation, I examine whether the gut microbiome can help reveal how animals experience environmental stress, and whether it can contribute to the assessment of wild animal welfare. Using white-footed mice (Peromyscus leucopus) as a study system, I combine a conceptual review with captive and free-living experiments to test how chronic auditory predator cues affect the microbiome, fecal glucocorticoids, and behavior. Across these studies, predation risk was associated with shifts in gut-microbial community structure and temporal dynamics, with the strongest patterns emerging at the level of overall community reorganization rather than consistent changes in alpha diversity or single taxa. In free-living mice, microbial responses to predation risk were only weakly aligned with endocrine and behavioral measures, suggesting that responses to fear in the wild are often subtle, multidimensional, and not necessarily coupled across biological systems. Together, this work shows that the gut microbiome is sensitive to ecologically relevant stressors and may provide a useful new tool for understanding animal welfare under natural conditions.
CCB-340
Michael Sheriff
5089996894
msheriff@umassd.edu