9627462 Farouk Organism-flow interactions are potentially important in a wide variety of ecological settings. Unfortunately, it is often difficult to quantify the complex flow fields in which organisms actually live, thereby limiting our understanding of the direct and indirect effects of flow on various ecological processes and patterns. This collaborative research, which combines expertise in aquatic ecology and mechanical engineering (simulation and measurement of flow and transport processes), will apply recent methodological advances in engineering to describe the flow environments inhabited by stream benthic animals. Specifically, the research will use computational fluid dynamic models t o simulate benthic flow fields, and will validate the predictions using recently developed acoustic Doppler velocimeters as well as hot-film anemometers. These validated models can provide detailed descriptions of spatial and temporal variations in flow field characteristics. The effects of different flow fields on pattern of feeding, habitat selection, and distribution of suspension-feeding stream insects will then be examined via experimental studies in laboratory flumes and in the field. How such organism-flow relationships vary with spatial scale will also be examined. This 'Small Grant for Exploratory Research' will demonstrate the value of this interdisciplinary approach for ecological studies in streams and rivers. It can ultimately lead to major advances in the study of organism-flow interactions in a wide variety of ecological systems.