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▪ Ephemeroptera • Plecoptera ▪ Triooptera • Diptera • Coleoptera • Oligochaeta ■ Other 2012 Locke Lake `Below' Data Summary Family Biotic Index (FBI): Our 2012 SHEP field sampling results produced a score of 5.6 for the Locke Lake `Below' site. This score corresponds to a "Fair" rating on the Family Biotic Index stream health chart. This compares to stream health scores from 2010 (5.0) and 2011 (5.7). The 2012 FBI score is similar to 2011, though a higher diversity of invertebrates with lower tolerance values helped the FBI score slightly. 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. 629 invertebrates were identified in this sample. This sample size is excellent. Dominant Family: The dominant family was Chironomidae. Chironomidae dominated 61.4% of the sample, and has a tolerance value of 6 on a scale of 0 -10 (the lower the tolerance value, the lower their tolerance to pollution). They are a very abundant and diverse group of aquatic insects, and it is common for them to dominate samples (Guide to Aquatic Invertebrates of the Upper Midwest, R.W. Bouchard, Jr). Number of Families: In 2012,15 families were identified in the sample. This compares to 13 families in 2011 and 11 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, 3 EPT families were identified and made up 23% of the sample. • •