ABSTRACT
The assessment of the system based on its physical characteristics is called a habitat assessment. Biomonitoring and habitat assessments are two tools that stream ecologists use to assess the water quality of a stream. Biological monitoring involves the use of organisms called assemblages—periphytons, fish, and macroinvertebrates—to assess environmental conditions. Biological observation is more representative as it reveals cumulative effects as opposed to chemical observation, which is representative only at the actual time of sampling. Again, the presence of different assemblages of organisms is used in conducting biological assessments and/or biosurveys. Some of the advantages of using periphytons, benthic macroinvertebrates, and fish in a biomonitoring program are presented in this chapter. Monitoring of the fish assemblage is an integral component of many water quality management programs, and its importance is reflected in the aquatic life use-support designations of many states. Fish bioassessment data quality and comparability are assured through the utilization of qualified fisheries professionals and consistent methods.
