National Water Quality Assessment Program (NAWQA)

Tennessee River Basin Study

 

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The types and numbers of fish species present in a stream can be used as an indicator of both the past and present condition of the watershed.  Because most species require clean substrate to spawn and clear water to feed, their condition and presence can be used to develop biological indices that serve as a “health” rating for a stream, to evaluate a particular land-use type, or monitor water quality impacts below a point-source discharge. Various techniques are utilized to collect fish such as, hauling a seine through pools and backwater areas to actively pursuing fish with a towed electrofishing unit.

     

Last Modified 7/3/01
maintainer rmitchel@usgs.gov