| This dissertation focuses on the analysis of freshwater mussel populations through the development and application of the Mussel Dynamics Model (MDM), a mathematical model that captures relevant mussel and environment interactions and simulates inter- and intra-species food competition.; In the MDM, various modules provide input information defining the environmental conditions in the domain. This information is summarized by a habitat suitability score that acts as a forcing function to drive the response of individual mussels. Mussel behavior is simulated by an Individual Based Model which, through simplifications, can render a Cellular Automata or a Differential Equation model. The functional processes contained in the model are those acting at the scale of meters and which ultimately may influence the community distribution at the scale of 10s to 100s of meters. These processes represent mussel behavior and evolution in terms of mortality, life stage, growth, food competition, reproduction, larvae dispersion, and adults movement as they search for suitable habitats.; The MDM predictive capabilities were verified, using the freshwater mussel community of Pool 16 in the Upper Mississippi River. Suitable areas for mussel survival were identified based on substrate and hydrodynamic variables; particularly by the application of a substrate stability parameter. Mechanisms of mussel bed formation were successfully captured by the model. Long term simulations were made to observe the population evolution and emerging patterns of organization. Sensitivity of the results to the competition mode, food availability, and hydrodynamic variability were tested. The effect of zebra mussel infestation on native freshwater mussel populations was assessed in terms of food competition.; The MDM simulation integrates many sources of information, each with its own uncertainty. In addition, there is only limited data to verify the simulation results. For these reasons, the results are somewhat more qualitative than quantitative, but provide a framework for future research and applications. Given the scale of analysis, the results obtained reasonably represent observed patterns of freshwater mussel population dynamics. In the future, MDM can be a useful tool for evaluating the effects of alternative management practices on this imperiled faunal group. |
