By Jeffrey R. Deacon and Scott V. Mize

Available from the U.S. Geological Survey, Branch of Information Services, Box 25286, Denver Federal Center, Denver, CO 80225, USGS Fact Sheet FS-122-97, 6 p.

The complete document is also available in pdf format: FS-122-97 (391 KB)
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Natural and human factors in the Upper Colorado River Basin result in differences in water quality and fish habitat. Fish community composition is associated with differences in water temperature, concentrations of dissolved solids and suspended sediment, elevation, habitat, and land use.

Introduction

The sampling design of the National Water-Quality Assessment (NAWQA) program emphasizes a multidisciplinary approach using physical, chemical, and biological information to provide multiple lines of evidence to describe water-quality conditions. The composition of fish communities at stream sites representing selected environmental settings is one characteristic assessed as part of the NAWQA program (Meador and others, 1993a). The presence and abundance of fish species can be related to water chemistry, physical habitat, and land-use activities to provide a more complete picture of water quality across a river basin. Although fish communities may have a high degree of natural variability, they can be useful indicators of ecosystem health (Moyle, 1994). Berkman and others (1986) recommended fish be given consideration in biological water-quality monitoring of streams because they generally are perceived by the public to be ecologically relevant, and they are directly related to legislative mandates because of human health and endangered species concerns. This fact sheet summarizes the results of an August 1996 fish survey and relates these results to natural and human factors that affect water quality and physical habitat in the Upper Colorado River Basin (UCOL) study unit in Colorado.