National Water-Quality Assessment (NAWQA) Program - South Platte River Basin

index of Biotic Integrity (IBI)

An index of biotic integrity (IBI) developed for fish in the South Platte River Basin (Schrader, 1989) can be used as a biological indicator of habitat and water-quality conditions. An IBI for a site was calculated by summing the ranks of three categories of fish-community characteristics; the number and types of fish, fish feeding habits, and fish abundance and health. The ranks were determined by comparing a fish-community characteristic at a site to those expected under natural conditions. The site scores were then grouped into three classes; significantly degraded, moderately degraded, and minimally degraded.

Schrader, L.H., 1989, Use of the index of biotic integrity to evaluate fish communities in Western Great Plains streams: Fort Collins, Colorado State University, Master's thesis.

Back to the previous page

Accessibility FOIA Privacy Policies and Notices

U.S. Department of the Interior | U.S. Geological Survey
URL: https://co.water.usgs.gov/nawqa/splt/html/ibi.html
Page Contact Information: gs-w-codist_webmaster
Page Last Modified: Friday, 16-Dec-2016 19:04:03 EST