Quantifying the effect of marine predator foraging behaviors in patchy prey environments on ecosystem productivity, diversity and function using novel mathematical, theoretical and empirical approaches

• Applicant: Dr. Susanne Menden-Deuer
• Subject Area: Ecology and Biodiversity of Animals and Ecosystems, Organismic Interactions
• Term: from 2004 to 2008
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5439279

The goal of this research is to develop mathematical models that establish a quantitative relationships between smallscale, individual movements of marine predators, and their long-term, large-scale effects on ecological rates. Zooplankton foraging is of fundamental importance in structuring marine food webs, which drive ecological dynamics, impact fisheries production and modulate the global carbon cycle. Many predators have behavioral responses to prey, e.g. they turn more in the presence of prey. The ecological consequences of such behaviors on growth and grazing rates can be understood within the context of biased random walk theory. Development of this theory has been limited by lack of data that simultaneously tracks individuals and populations. Recently, I have collected millions of these observations. First, I propose to develop biodiffusion models which embed my observations in a theoretical framework and generate predictions of biological rates. Second, I will apply these models to movement data of threatened marine predators (sharks, whales, seals) to predict their habitat use. By linking individual movements with ecological processes, this work will support marine conservation and enhance our quantitative understanding of the ecology of marine ecosystems.

• DFG Programme: Research Fellowships
• International Connection: USA