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Number of individuals: A large sample offers more confidence for a more reliable data set. SHEP protocol requires a minimum of 100 individual invertebrates to be picked and identified per sample. 146 invertebrates were identified in this sample. This sample size is adequate. Dominant Family: The dominant family was Gammaridae (scuds). Gammaridae dominated 55.5% of the sample, and has a tolerance value of 4 on a scale of 0 -10 (the lower the tolerance value, the lower their tolerance to pollution). They are closely related to Hyalellidae (note the pollution tolerance difference). The distinction between the two families is the flagellum found on the antennae of Gammaridae. They are important food sources for fish and invertebrate predators. They can be extremely abundant in water bodies without fish and are important in the breakdown of organic matter. (Guide to Aquatic Invertebrates of the Upper Midwest, R.W. Bouchard, Jr). Number of Families: In 2012, 16 families were identified in the sample. This compares to 19 families in 2011 and 10 families in 2010. In general, a more diverse sample suggests a healthier stream environment. EPT: Ephemeroptera - Plecoptera - Tricoptera (Mayfly - Stonefly - Caddisfly) are three Orders of invertebrates with low tolerance to pollution. The more of these families in a sample, the better. More than 10 -12 families is considered good. In 2012, 2 EPT families were identified in the sample and made up 20% of the sample. 4.2.5 Clearwater Creek Overall Data Summary Interpretation of the Hilsenhoff Biotic Index Sampling Sites 2007 2008 2009 2010 2011 2012 Clearwater Creek 5.9 5.5 63 4.5 4.7 4.6 Cross Check 5.9 6.8 4.7 Na Na Na Overall, Clearwater Creek site results indicate relatively stable stream conditions, with increasing populations of lower pollution tolerance families in the last three seasons. Clearwater Creek continues to post some of the strongest stream health scores in the Rice Creek Watershed. The 2012 Family Biotic Index score of 4.6 indicates a stream health score of "Good ". • •