"Yellow perch Perca flavescens are widely distributed across North America where they inhabit a variety of aquatic ecosystems, playing an ecologically and economically significant role as both predator and prey. Like many fishes, successful recruitment of yellow perch depends on the availability of suitable densities and sizes of zooplankton prey at critical early life history periods. Thus, evaluation of prey selection may lend insight into processes driving year class strength. In order to assess prey selectivity, we collected larval yellow perch and zooplankton samples across a variety of inland lakes in Michigan's Lower Peninsula. The size structure of zooplankton taxa (e.g. Bosmina spp., cyclopoid copepods) was quite consistent across multiple system types, but zooplankton densities varied widely both within and between lakes. Selection for prey type and size varied in relation to fish size, but remained relatively consistent between eutrophic, mesotrophic and oligotrophic lakes. In my study lakes, I concluded that rotifers were not an important first food of larval yellow perch and analysis of prey selection patterns is confounded by a summative interaction of morphological limitations of the predators with behavioral preference for specific prey types within prey size classes. Additionally, I demonstrated that large numbers of samples were necessary to improve the level of confidence in measuring prey availability (e.g. density, species composition)."--Page ii.
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