¹Department of Entomology, Michigan State University, East Lansing, MI 48824 USA
²King County Department of Natural Resources, Water and Land Resources Division, Seattle, WA 98104 USA
³School of Natural Resources and Environment, University of Michigan, Ann Arbor, MI 48109-1115 USA
⁴California Cooperative Fisheries Unit, Department of Fisheries, Humboldt State University, Arcata, CA 95521 USA
⁵Department of Biology, Central Michigan University, Brooks 156, Mount Pleasant, MI 48859
⁶Current address:Tompkins Cortland Community College, Department of Biology, 170 North St., Dryden, NY 13053

*Corresponding author: wesselk@tc3.edu

Abstract

   Non-wadeable rivers are relatively understudied compared to smaller, wadeable streams. Currently, protocols exist in most states, including Michigan, to evaluate the ecological condition of wadeable streams, but few protocols exist for larger, non-wadeable rivers. The goal of this research was to develop a multimetric index of biological integrity for Michigan’s non-wadeable rivers. We sampled 28 unique non-wadeable river reaches in Michigan that encompassed a wide range of human impacts and ecological conditions. In each reach, we collected physical, chemical, and macroinvertebrate samples. Using several techniques to eliminate redundancy among metrics and identify those biological attributes that correlated with anthropogenic influences, we developed a useful protocol that will allow the rapid bioassessment of non-wadeable rivers in Michigan. When used together with the Non-wadeable Habitat Index, the Non-wadeable Index of Biotic Integrity (NW-IBI) will allow objective evaluation of non-wadeable rivers in Michigan.