Assessing Biological Effects of Animal Production on Intermittent Coastal Plain Streams

Abstract. Biotic indices increasingly are being used by state and federal agencies to evaluate water quality. The application of existing biotic indices to intermittent Coastal Plain streams is problematic because of unique habitat and flow characteristics. Managers must field-test biotic indices before accepting them for use in this area. This study in South Georgia evaluated the appropriate sampling season for biological monitoring and tested whether existing biotic indices correlated to physical and chemical impacts. Early results showed that index scores changed drastically with season and that different indices yielded conflicting assessments of stream health in intermittent streams of the Coastal Plain. At these sites, the EPT Index (Ephemeroptera/ Plecoptera / Trichoptera) was a better indictor of stream health than the North Carolina Biotic Index because it accurately reflected physical and chemical stream conditions.