In this dissertation I defined and evaluated the spatio-temporal dimensionality of carnivore ecology via philosophical analysis, literature synthesis, and empirical study. In Chapter 1, I analyzed philosophical and empirical arguments that postulate model section techniques like AIC empirically justify a value for simplicity in statistical modeling of ecological phenomena. My analysis drew upon an extensive case study regarding the reintroduction of wolves into Yellowstone National Park, USA. I showed that assumptions of stationarity required for the epistemic justification of simplicity are generally violated when considering complex ecological phenomena. I concluded that simplicity plays a greater epistemic role in explaining past events than it does in predicting future ones, thereby tempering the value traditionally lauded upon simplicity in ecological study.In Chapter 2, I evaluated the niche width of a mesocarnivore species commonly assumed to be a forest specialist (the pine marten Martes martes). I used a large-scale spatial occupancy model to show that although pine martens were positively associated with forested habitat, they occurred across a remarkable variety of habitats and exhibited no negative association with non-forested areas. I concluded that evaluations of species’ niche width should be informed by large -scale studies rather than local assessments. In Chapter 3, I examined the effects of large carnivores on the grouping behavior of African ungulates. I modeled spatial predation risk from two carnivore species in three ways: 1) as a function of habitat, 2) as a function of carnivore occurrence, and 3) as a function of where carnivores tended to kill prey. I found that prey behavioral response to risk varied across these three expressions in complex ways, highlighting the need for a multi-expressional approach to assessing risk effects in multi-species systems.In Chapter 4, I coupled a conceptual framework with a formal literature review to synthesize the ways that predation risk was measured and modeled in carnivore-ungulate systems. I found striking variability in methodological approach to measuring and modeling risk. I synthesized our findings into a cohesive framework based upon predator-prey theory and centered around long-term risk, short-term risk, and habitat characteristics. I concluded with a call for risk-related studies to employ a multi-dimensional approach and to evaluate multiple, competing hypotheses. In Chapter 5, I applied the recommendations generated in Chapter 4 in a study of human-carnivore interactions in an expansive semi-urban park system. I employed a multi-dimensional spatio-temporal framework that revealed how humans and carnivores share the city by avoiding one another in space and time.I conclude the dissertation with a summary of lessons learned and a look ahead to future research. Future studies that critically evaluate ecological phenomena across multiple spatio-temporal dimensions via a variety of variable expressions will be most efficient in separating out ecological signals from noise and locating the characteristic scales upon which such phenomena occur. Such research will bring clarity not only to ecological theory, but will facilitate more efficient conservation and management strategies by providing clear linkages between ecological processes and the scales at which they can be manipulated or influenced.
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