UC San Diego

In this dissertation, I investigate a series of seemingly disparate topicsÑthe theorem of a mathematician working on turbulence in fluid flows, the collapse of the great California sardine fishery in the mid 20th century, competition between zooplankton grazers in a marine mesocosm, and the occurrence of influenza in the tropics. All of the work, however, is motivated by the ongoing endeavor to develop ecosystem-based approaches to fisheries management. Ecosystem-based management remains an open problem in part because the fundamental complexity of natural systems does not readily map onto the set of tools we’ve developed through our very successful accomplishments in engineering. In combination, the chapters of this thesis address this disparity by developing practical, empirical tools for studying and managing ecosystems that directly address the complex reality of nature.