To explore factors that influence fish community organization and recruitment in Lake Erie, I used four approaches. First, I collaborated on an ecosystem modeling project that explored how anthropogenic disturbance might cause the Lake Erie ecosystem to take on several configurations (e.g., pristine, degraded). Analyses of differences among ecosystem configurations suggest that both protecting natural land from development and limiting phosphorus inputs are as critical to maintaining healthy fish communities as is setting appropriate commercial harvest regulations. Second, by merging bottom trawl data from western and central Lake Erie with species-specific life-history information (e.g., tolerances to environmental degradation, feeding and temperature preferences), I demonstrate that reduced point-source inputs of phosphorus (i.e., oligotrophication) have driven fish community rehabilitation during 1969-1996, whereby species intolerant of eutrophy (i.e., anoxia, turbidity) have begun to replace tolerant species. In turn, species turnover has caused species richness to decline in the west basin, but increase in the central basin. Given that several recovering intolerant species are desired sport or commercial fishes, these analyses support some of the hypotheses generated from the ecosystem model. Third, using multiple regression modeling, I explored ecological mechanisms underlying yellow perch (Perca flavescens) recruitment and growth in western and central Lake Erie during 1969-1998. During this time, reductions in point-source loading of phosphorus appear to have caused recruitment variation to switch from control by temperature to control by stochastic factors that influence non-point source loading of phosphorus (e.g., precipitation-driven river discharge and runoff). Although system productivity was unrelated to growth, interspecific competition with exotic white perch (Morone americana) appears to have negatively influenced yellow perch growth. Conversely, warm temperatures appear to enhance growth either by stimulating early spawning or by increasing zooplankton availability to fish. Finally, I combined recent (1994-1998) larval yellow perch growth, diet, and hatch date information with temperature, zooplankton, and potential competitor (e.g., exotic white perch) abundance information to test the relative importance of temperature and interspecific competition to yellow perch growth. Temperature, through both hypothesized pathways, does indeed regulate larval growth, whereas interspecific competition with white perch appears unimportant. Ultimately, this work exemplifies how multi-scale, mechanistic investigations of fish population and community dynamics can enhance the ability of resource managers to understand and anticipate changes in their fisheries.