Evaluating Fish Community Changes to Stream Flow Alterations

The information needed to address the diversity of ecological flow issues will continue to arise due to climate change and increased demand for water, making stream flow management a complex and long-term issue.  In order to make stream flow management decisions using the best available science, we developed a comprehensive geodatabase to determine where biologic, hydrologic, stream temperature, land-use, and flow alteration data exists for Missouri streams.  We identified potential analysis sites to determine provisional flow ecology relationships (e.g. how fish populations characteristics are related to flow regime), where sites from multiple datasets are paired temporally and spatially using a geographic information system.  Initial datasets included 1700 fish community sites and 480 stream gages, but only 125 sites with both streamflow and fish community data for analysis.  Sites with repeat sampling have been targeted to better understand variability of fish community metrics over time, but there were less than 40 of these sites statewide.  To further understand how flow alterations affect riverine systems and their biota we developed metrics for all fish sampling sites that define effects of impoundments and metrics for the effect of withdrawals using their natural surrogate, losing streams.