In my dissertation, I use agent-based modeling and observational long-term behavioral data to elucidate how social and ecological factors affect foraging behavior of spotted hyenas, a highly social carnivore, in the Maasai Mara National Reserve, Kenya.Group hunting is common among social carnivores, but in societies structured by linear dominance hierarchy, access to rewards from hunting are not evenly distributed among group members. In my first chapter, I explore how the inequality of resource distribution due to social rank influences the evolution of cooperative hunting in a digital evolution experimental world. The system reflects spotted hyena society, where an individuals’ dominance rank affects their priority of access to critical resources with dominant individuals receiving greater benefits. I found that group hunting evolved at different rates depending on how equitably rewards were shared and high-ranking agents that benefited the most from group hunting were more likely to group hunt. These results provide insights into mechanisms that may promote cooperation in animal societies structured by dominance hierarchies. In my second chapter, I use long-term behavioral data to investigate hyena hunting patterns and how attributes of both hunters and prey influence hunting behavior. Dominance rank, age, and sex strongly influence hyena behavior and access to resources. Additionally, prey attributes can also influence hunt success for predators. I examine how attributes of spotted hyenas and their prey affect hunting success and hunting group sizes and compare these results to previous work in this same region from 1988-1995, representing a period with lower human activity, a smaller hyena population, and more abundant prey. Prey species and prey age affected hunt success, as well as the age of the hunter when hunting alone. Hyenas hunted prey that were harder to capture in groups more often, and mean hunting group size varied by social rank and age. Group hunting was more common during this study period, possibly reflecting the increasing hyena population and decreases in easier to capture prey. These results demonstrate that attributes of predators and their prey influence hunt success and hunt grouping behavior in spotted hyenas and are important to consider in predation studies. In my third chapter, I investigate dietary flexibility in hyenas by comparing feeding behavior (1) contemporaneously among hyenas inhabiting areas with different ecological conditions, and (2) longitudinally across the same population as ecological conditions change in a region that has experienced decreasing wild prey and increasing livestock presence. I found that in both sites, hyenas primarily consumed the prey type that is most available. In my longitudinal comparison, I found that hyenas at one site ate more livestock, and became less reliant on resident prey, as livestock increased there over time. Long-term changes in hyena diets reflected declines in wild prey abundance and increases in livestock presence. This work demonstrates the flexibility of hyena foraging across seasons and in the face of long-term changes in prey availability. By using agent-based simulations and empirical data, this dissertation deepens our understanding of the mechanisms influencing hunting decisions, as well as the complex social and ecological aspects that shape foraging behavior in spotted hyenas across various temporal scales. I discuss how observed changes in behavior could impact broader ecological interactions, ecosystem processes, and community ecology.
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