Explaining First Year Growth and Survival of Sander spp. Using Historical Data Analysis

Long-term comprehensive datasets are extremely useful for documenting ecosystem change, assessing management practices, and identifying and investigating testable hypotheses. Although reservoirs fisheries receive more angling pressure than all other freshwater systems, availability of fish data from reservoirs is limited. In 2003, the Ohio Division of Wildlife (DOW) implemented a standardized sampling program designed to, among other things, evaluate management practices and amass time series data for retrospective studies. Annual stock assessment data are available for a suite of reference reservoirs selected based on geographic distribution, historical data and reservoir attributes.  These systems represent the full range of characteristics (e.g., size, land use, productivity) of Ohio reservoirs.  Here, we use historical fish records from the Ohio DOW monitoring system and other readily available sources of information (e.g., air temperature, water levels, turnover) to evaluate first year survival of stocked Sander spp. in Ohio reservoirs. We expected that reservoir turnover, productivity, and the relative timing of stocking and predicted peak prey availability set recruitment potential in Ohio reservoirs and thus are more important than the numbers and sizes of fish stocked, predator density, reservoir water levels, or temperature. Through this analysis we seek to advance our general understanding of Sander spp. recruitment, thus contributing to design of stocking programs, and to identify data gaps that limit application of resource-intensive fish data, thus improving future data collection and analysis.