Foraging in a Complex World: From Individual Flight Performance to Collective Behavior in Bumblebees (Bombus Impatiens)

Abstract

Foraging is a crucial and remarkably complex behavior that is key to survival. For social insects such as bumblebees, successful foraging depends on a combination of individual traits (e.g. physiological and biomechanical performance of individual workers) and collective behavioral strategies for regulating food intake at the colony level. Here, I use foraging behavior in bumblebees as a lens to explore how insects cope with challenging, natural environments, scaling from individual performance to group dynamics. First, I explore how bumblebee foragers cope with structural clutter, with particular emphasis on the allometry of maneuverability and flight performance (Chapter 1). Next, I investigate how the variable, turbulent wind flows that characterize natural environments affect flight stability (Chapter 2) and landing behavior (Chapter 3) of bumblebee foragers. Moving from the individual to the colony level, I then develop an automated, high throughput behavioral tracking system (Chapter 4) capable of following uniquely identified individuals in visually complex environments, and use this system to explore the distribution and regulation of foraging activity across entire bumblebee colonies (Chapter 5). Finally, I use this same tracking system to examine the effects of exposure to a common neonicotinoid pesticide (imidacloprid) encountered during foraging, and show that it disrupts aspects of social behavior and communication in bumblebee colonies (Chapter 6).