Macroinvertebrate Studies

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Macroinvertebrates are organisms that lack a backbone and are visible to the naked eye.  In freshwater streams, they form the base of the aquatic food chain and include insects, crayfish, clams, mussels, snails, worms and others.  Most macroinvertebrates dwell in riffle areas of a stream and cannot escape changes in water quality. The density of species decreased from hundreds in upstream areas in Huff Run, to less than ten in lower reaches.  Those very few living in the lower part of the watershed were largely pollution-tolerant.

View Mount Union 2002 Macroinvertebrate Study on Reach 6 in Huff Run, This study found that Reach 6 has poor water quality when before it was unknown.

Another macroinvertebrate study has been conducted by Mount Union College in the Summer of 2004. Although flooding caused some data to be lost, the findings are below:             HR0(upstream)        HR1 (upstream)        HR28 (near Mineral City)          Midge larvae              10                         1                                 2 Cranefly larvae                2                          0                                0 Caddisfly Larvae              14                         2                                3 Mayfly nymphs              4                          1                                1 Crayfish             1                          0                                 0 Aquatic Worms               0                           0                                1                                                                                                                                ICI Score            11                         7                                   8 Site condition:     Fair                     Poor                             Poor Other data has indictated that perhaps more data was lost than expected because HR1 and HR0 have been found to have good to excellent water qualtiy. Study conducted by Lainey J. White

The ICI (invertebrate community index) score is based on the amount of pollution tolerant or pollution intolerant  species found at a site.  Learn more at this OSU Extension page.