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of zero indicates very sensitive to organic pollution. A '10' indicates very tolerant of organic pollution. The FBI for a site is the weighted average of the biotic indexes for all of the invertebrates in the sample. The FBI summarizes the various pollution tolerance values of all families in a sample. Pollution intolerant families such as stoneflies (FBI of 0 — 2) can only survive in excellent water quality. Pollution tolerant organisms such as leeches and aquatic earthworms can live in clean water or poor quality water. They have high FBI values (8 — 10). According to Hilsenhoff, who developed this metric, "Use of the FBI is advantageous for evaluating the general status of organic pollution in streams within a watershed for the purpose of deciding which streams or watersheds should be studied further." Historically, the lowest (best) FBI value reported by our monitoring was a 4.4 score at Hardwood Creek `Below' in 2011. The highest (poorest) historical FBI value reported was an 8.8 at the Rice Creek `Above' site in 2006. Index of Biotic Integrity (IBI): "A synthesis of diverse biological information that numerically depicts associations between human influence and biological attributes. It is composed of several biological attributes or `metrics' that are sensitive to changes in biological integrity caused by human activities." Source: Volunteer Surface Water Monitoring Guide, MPCA, 2003 Incomplete Metamorphosis - occurs in the Ephemeroptera, Plecoptera, Odonata and Hemiptera. The life cycle includes the following stages: egg, early instar larva, late instar larva and adult. This program monitors the larval stages of development. Macroinvertebrate — An invertebrate that can be seen with the naked eye. Metric- A measure of stream health calculated using data from the macroinvertebrate monitoring. The family biotic index (FBI), EPT and number of families (family richness) are examples of metrics. Metrics are used to help analyze and interpret biological data. Metrics are often compared to charts that place the values into stream health categories. Number of Families - The number of different benthic macroinvertebrate families found at the site, also known as family richness. In general, more diversity is better. Therefore a larger number of families may reflect a healthier community than a smaller number. The largest number of families (20) was discovered at the Hardwood Creek `Below' site, while the fewest number of families (10) were found at the Rice Creek `Above' sampling location. Number of Organisms Identified- The protocol used requires a minimum of 100 organisms to confidently assess a site. When fewer than 100 organisms are identified, the information is still useful, but we cannot be as confident about characterizing the site's health. Teams in this circumstance will select another sub - sample of a site sample and identify all organisms in the second sub - sample in addition to the original sub sample. Scores are tallied based on the combination of both sub - sample results, often resulting in larger numbers of individual macroinvertebrates identifies. •