RUI: Modeling Spatially-Structured Dynamics for Benthic Predation

California State L A University Auxiliary Services Inc., Los Angeles CA

Investigators

Abstract

There is a growing realization that spatially- structured dynamics are an important consideration for many ecological systems. This is particularly true when local interactions among individuals of a sedentary species are intense. Intertidal communities often display intense local interactions among individuals, and the dense populations, small spatial scale, and striking distribution patterns of the communities suggest that this system is especially apt for investigations of spatially-structured dynamics. Despite this fact, little work has been done to develop a spatially-explicit theory for intertidal benthic communities. This area of ecology is ripe for the development and testing of mechanistic spatially-explicit dynamic models. The first objective of this study is to develop a spatially-explicit "multi-model" approach to the study of predation in benthic communities. Research will focus on populations of the intertidal mussel Mytilus califonianus, an important dominant competitor along rocky shores of the Pacific coast, and its predators, the sea star Pisaster ochraceus in the Northwest and the spiny lobster, Panulirus interruptus, in Southern California. Three classes of spatially-explicit models will be developed and analyzed: (1) cellular automata, (2) analytical models consisting of partial and ordinary differential equations, and (3) individual -based models. Comparison and cross-validation will occur among models in order to take advantage of the strengths and that each has to offer. Whenever possible, model parameter values will estimated from field and laboratory data, model predictions will be compared to fine-scaled distributional data being collected in the field, and the model simulations will be used to suggest novel field experiments. The second objective is to provide a rich interdisciplinary training experience for master's students who are interested in applying the tools and techniques of mathematics and computer science to ecological problems. Project funds will be used to provide full-time support to three graduate students who will be recruited from the ethnically-diverse student body at Cal State LA and neighboring institutions. A postdoctoral research associate will be hired to develop the individual-based models and assist with student mentoring. Interdisciplinary programs of study will be designed for each student and training will include participation in an NCEAS workgroup and a summer field experience. This project will advance our knowledge of how nearshore marine benthic communities develop and are maintained and will contribute to the training of the next generation of ecologists.