Development, Validation, and Application of a Fish-Based Index of Biotic Integrity for Wisconsin's Large Warmwater Rivers

Publisher Website
Google Scholar
Abstract
We used fish assemblage data collected by daytime electrofishing during 1996–1999 from 155 main-channel-border sites on 30 large warmwater rivers in Wisconsin to construct, test, and apply an index of biotic integrity (IBI). Our goal was to develop an effective and rapid way to use fishes to assess the environmental quality of river ecosystems in the state. Fourteen sites were visited more than once for a total of 187 samples, 101 of which (randomly chosen) were used to develop the IBI and the remaining 86 to test it. Prior to sampling, sites were classified as “least impacted” or as affected by impoundments, daily “peaking” flows from hydropower dams, non-point-source pollution from the watershed, point source pollution from industrial and municipal discharges (within the last 35 years), or multiple human impacts. Of the 26 potential IBI metrics considered, 10 were chosen: the total weight of the catch (excluding tolerant species); the number of native, sucker, intolerant, or riverine specialist...