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DUTCH CREEK <br /> This stream was sampled in May and June, 1989. When sampled in May, <br /> the macroinvertebrate community indicated stress conditions in this stream <br /> reach. None of the taxa were present in resident population numbers. The <br /> most tolerant species were best able to live under the circumstances. Less <br /> than resident population numbers for all of the taxa indicated instability <br /> and possibly a toxic effect from something within the drainage. <br /> When sampled in June, conditions appeared to have improved. <br /> Cleanwater species had better diversity but were still not present in <br /> resident population numbers. Moderately tolerant taxa present indicated at <br /> least fair conditions in this ecosystem. There were some indications of <br /> sediment, organic nutrients, and possibly a chemical imbalance in this <br /> ecosystem. The community did not have a good trophic balance on either of <br /> the dates sampled. Analysis elements indicated stress conditions in this <br /> ecosystem; the standing crop and diversity were low. <br /> The potential for a resident fishery on this stream appeared to be <br /> poor. The macro invertebrate biomass of 0.1 g/m2 in May and 0.4 g/m2 in <br /> June would be limiting to the number and size of fish that could be <br /> supported in this ecosystem and was low for a stream with 71 mg/l <br /> alkalinity. The number of cleanwater species present indicated that there <br /> was some good instream substrate and fairly good water quality on the June <br /> sampling date. <br /> The BCI of 85 in May would ordinarily indicate good conditions in an <br /> ecosystem; however, it was based on a community where none of the taxa had <br /> resident population numbers, thus there were stress conditions in this <br /> ecosystem. The BCI value of 78 in June indicated fair conditions, but low <br /> population numbers indicated even more stress in this ecosystem. Three of <br /> the 25 taxa in the community had resident population numbers, which <br /> indicated an improvement over conditions found in May. It appeared there <br /> would be opportunities for management to improve the instream habitat <br /> quality, water quality, and possibly riparian habitat quality in this <br /> aquatic ecosystem. <br /> 49 <br />