Behavioral Ecology of the American Alligator (Alligator mississippiensis) in Human-Dominated Landscapes of Coastal South Carolina
Date of Award
Doctor of Philosophy (PhD)
Forestry and Environmental Conservation
Catherine M. Bodinof Jachowski
When wildlife habitat is developed to accommodate growing human populations, wildlife are forced to move to undisturbed landscapes or to acclimate to a novel, anthropogenic environment. In this dissertation, we investigated the behavior and ecology of the American alligator (Alligator mississippiensis) in coastal, residential resort communities with an overarching goal of identifying behavioral patterns of alligators that can inform risk management strategies. In Chapter One, we compared the space use of male and female alligators in primarily wetland versus residential landscapes across three seasons to determine if and how space use behaviors of alligators differ. We found that alligator home ranges in residential landscapes were constrained around discrete freshwater features and included greater access to saline aquatic resources, and sex and seasonal differences in resource selection were muted compared to that of wetland alligators. Establishing that residential alligators use space differently, we estimated alligator abundance in seven golf courses to understand how many alligators humans encounter in residential landscapes and the factors influencing humans’ abilities to detect alligators that are present in Chapter Two. We found that alligator abundance was greater in areas with more freshwater alligator habitat potentially reaching similar densities to alligator populations in relatively undisturbed environments, and humans’ ability to detect alligators was related to the configuration of alligator habitat in the landscape and physiological and behavioral limits of an alligators’ risk-taking behaviors. In Chapter Three, we investigated how human-alligator interactions impact alligators’ tolerance of closely approaching humans in residential landscapes. We found that alligators exposed to aversive treatment by humans over ten years were 2.57-11.11 times more likely to flee from approaching humans, depending on alligator size, than alligators with primarily benign experiences with humans. In Chapter Four, we built on evidence of alligator sensitization from Chapter Three using a before-after-control-impact experimental design to investigate if short-term capture-mark-release efforts produce similar sensitization effects on alligator behavior. We found that alligators exposed to one week of capture-mark-release were 1.65 times more likely to flee from humans after captures occurred than before captures. Collectively, our findings suggest that chronic exposure to humans can alter alligator space use behaviors in a way that can support similar population sizes to those in relatively undisturbed environments, but that acute experiences with humans can alter alligators’ perceptions of humans to promote alligator behaviors that correspond to tolerance or avoidance of humans. Risk management strategies can use this information to proactively manipulate alligators’ experiences with humans in a way that both increases alligators’ probability of flight and humans’ ability to detect alligators, and to improve residents’ education of when and where alligator interactions are most likely to occur.
Kidd-Weaver, Anjelika, "Behavioral Ecology of the American Alligator (Alligator mississippiensis) in Human-Dominated Landscapes of Coastal South Carolina" (2022). All Dissertations. 3182.
Author ORCID Identifier