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Family Biotic Index stream health chart. This is the first year data has been collected at <br />this site, and as a result no trend analysis information is available. <br />Number of individuals: A large sample offers more confidence for a more <br />reliable data set. SHEP protocol requires a minimum of 100 individual <br />invertebrates to be picked and identified per sample. 165 invertebrates were <br />identified in this sample. This sample size is adequate. <br />Dominant Family: The dominant family was Chironomidae. Chironomidae dominated <br />60.6% of the sample, and has a tolerance value of 6 on a scale of 0 -10 (the lower the <br />tolerance value, the lower their tolerance to pollution). They are a very abundant and <br />diverse group of aquatic insects, and it is common for them to dominate samples (Guide <br />to Aquatic Invertebrates of the Upper Midwest, R.W. Bouchard, Jr). <br />Number of Families: In 2012, 13 families were identified in the sample. In general, a <br />more diverse sample suggests a healthier stream environment. <br />EPT: Ephemeroptera - Plecoptera- Tricoptera (Mayfly - Stonefly - Caddisfly) are three Orders <br />of invertebrates with low tolerance to pollution. The more of these families in a sample, <br />the better. More than 10 -12 families is considered good. In 2012, 2 EPT families were <br />identified in the sample and made up 2% of the sample. <br />4.1.5 Rice Creek Overall Data Summary <br />Interpretation of the Hilsenhoff Biotic Index <br />Sampling Sites <br />2006 <br />2007 <br />2008 <br />2009 <br />2010 <br />2011 <br />2012 <br />Rice Creek `Above' <br />8.8 <br />7.9 <br />73 <br />7.0 <br />73 <br />7.8 <br />83 <br />Rice Creek `Below' <br />83 <br />6.7 <br />5.2 <br />63 <br />7.8 <br />7.8 <br />7.4 <br />Rice Creek `Irondale <br />Na <br />Na <br />Na <br />Na <br />Na <br />Na <br />6.8 <br />Cross Check 'Above' <br />- <br />- <br />- <br />6.8 <br />7.8 <br />Na <br />Cross Check `Below' <br />6.1 <br />6.8 <br />5.8 <br />- <br />- <br />7.4 <br />Na <br />While these sites had shown some improvement in recent years, recent stream health <br />scores remain elevated and indicate "Very Poor" stream health conditions overall. The <br />Family Biotic Index score of 8.3 at the Rice Creek `Above' site and the Family Biotic <br />Index score of 7.4 at the Rice Creek `Below' site indicates a stream health score of "Very <br />Poor ". <br />The Rice Creek `Irondale' site, which was a new monitoring location in 2012, showed a <br />stream health score of 6.8, indicating a stream health score "Poor ". Further long -term <br />sampling data is required in order to more accurately gauge the overall rate of stream <br />health change at these sites. <br />• <br />• <br />