BRC-BIO: The role of resources and competition in shaping fine-scale territorial and fission-fusion dynamics in a non-model population of a model species

Animal sociality often presents a paradox: individuals living in groups must share valuable resources—such as food, mates, and territory—while also striving to maximize their own reproductive and survival success. A central question in animal ecology, therefore, is why animals form groups and what the associated costs and benefits are. Lions in resource-rich savanna habitats have long served as a model for studying social behavior in mammals, with extensive research shedding light on the drivers and consequences of their group living. However, lions also inhabit a range of ecosystems beyond savannas. Recent comparative research by the principal investigator in a forested ecosystem demonstrates that lion social behavior is highly context-dependent, varying significantly with ecological conditions. This project builds on that insight by investigating lion sociality in a semi-arid environment—Kenya’s Tsavo Ecosystem. Using advanced biotelemetry, remote cameras, and direct observations, the study will track individual lions and their groups to identify the ecological drivers of social behavior in this non-model population. The project will also develop a new lion monitoring software, supporting long-term research, education, and conservation efforts. Additionally, by providing immersive field and analytical research experiences for undergraduates and post-baccalaureate researchers, while integrating findings into course curricula, this project advances the NSF mission of building a broad and robust STEM workforce. Dominant theories in animal behavior limit our understanding of nature by anchoring us to familiar—and sometimes biased—hypotheses derived from studies on iconic or model systems. Lions, for example, have significantly advanced our knowledge of animal sociality due to their complex fission-fusion group structures and the nuanced interplay of cooperation and conflict within and between males and femailes. However, the typical lion in scientific literature pertains to only a few populations inhabiting resource-rich savannas (e.g. Serengeti and Ngorongoro), thereby confining the socio-ecological understanding of a widely distributed species into overly deterministic frameworks. This project seeks to broaden that perspective by integrating detailed observational data with high-resolution movement tracking via proximity-enabled satellite telemetry to 1) examine territorial dynamics of male- and female-groups, and 2) identify individual-level factors governing social cohesion in lions in a prey-scarce, spatiotemporally heterogenous, semi-arid system. The project will also 3) develop a web-based software tool for curating, managing, and analyzing long-term behavioral and demographic data on lions. By moving beyond traditional model habitats, this project will investigate mechanisms underlying individual interactions in lions, and whether these interactions differ within and between males and females amidst varying resources and competition from co-predators. Ultimately, the project aims to reveal how ecological factors influence social decision-making and contribute to the evolutionary understanding of social variation in lions. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.