Assessment Comments
1997 Biocriteria: Fish IBI=44 (fair),35 (fair); BM-IBI = 63 (good), 71 (good).
Basis for Assessment
The assessment was based on data collected in 1997 for the Maple River watershed bioassessment project conducted as part of the DNR/UHL stream biocriteria project. A series of biological metrics which reflect stream water quality and habitat integrity were calculated from the biocriteria sampling data. The biological metrics are based on the numbers and types of benthic macroinvertebrate taxa and fish species that were collected in the stream sampling reach. The biological metrics were combined to make a fish community index of biotic integrity (F-IBI) and a benthic macroinvertebrate index (BM-IBI). The indexes rank the biological integrity of a stream sampling reach on a rising scale from 0 (minimum) to 100 (maximum).
Sampling was conducted at two sites on this river reach. The F-IBI scores were 44 and 35 (both in the "fair" category); the BM-IBI scores were 63 and 71 (both in the "good" category). The aquatic life use support was assessed as fully supported / threatened (=FST), based on a comparison of the F-IBI and BM-IBI scores with biological assessment criteria established specifically for the 2000 Section 305(b) report. The biological assessment criteria were determined from a statistical analysis of data collected at stream ecoregion reference sites from 1994-1998.
