10.6084/m9.figshare.5500201 Susan Cormier Susan Cormier Lei Zheng Lei Zheng Erik W Leppo Erik W Leppo Andrew Hamilton Andrew Hamilton Dataset for: Step-by-Step Calculation and Spreadsheet Tools for Predicting Stressor Levels that Extirpate Genera and Species Wiley 2017 Extirpation Conductivity Analysis Tool Sensitivity Distribution Stream Environmental Management Environmental Science Environmental Impact Assessment Ecological Impacts of Climate Change Environmental Monitoring 2017-11-10 06:25:17 Dataset https://wiley.figshare.com/articles/dataset/Dataset_for_Step-by-Step_Calculation_and_Spreadsheet_Tools_for_Predicting_Stressor_Levels_that_Extirpate_Genera_and_Species/5500201 In 2011, the U.S. Environmental Protection Agency (USEPA) released a field-based method for estimating the extirpation of freshwater aquatic benthic invertebrates by ionic mixtures dominated by HCO<sub>3</sub><sup>−</sup>, SO<sub>4</sub><sup>2−</sup>, and Ca<sup>2+</sup> measured as specific conductivity (SC). The estimate of extirpation was SC at the 95th centile (XC<sub>95</sub>) of a weighted cumulative frequency distribution (CFD) of a genus or species over a range of SC. A CFD of XC<sub>95</sub> values was used to predict the SC at which 5% of genera were likely to be extirpated. Because there are many uses for XC<sub>95</sub> values and many data sets that could be analyzed using this method, we laid out a step-by-step method for calculating XC<sub>95</sub> values and the stressor level that predicts a 5% extirpation of genera (HC<sub>05</sub>). Although the calculations can be done with a hand-held calculator, we provide access to 2 downloadable Microsoft Excel® spread sheet calculation tools that are easy to use to calculate XC<sub>95</sub> values, to plot a taxon’s XC<sub>95</sub> cumulative frequency distribution with increasing SC, and to plot probabilities of observing a taxon at a particular SC. They also plot cumulative frequency distributions of XC<sub>95</sub> values and calculate HC<sub>05</sub> values. In addition to the tools, we share an example and the output of XC<sub>95</sub> values for 176 distinct aquatic benthic invertebrates in Central Appalachia.