Improving Indicators for the Maryland Biological Stream Survey

Paul F. Kazyak

Maryland Dept. Natural Resources
Tawes State Office Bldg., C-2, Annapolis, MD 21401

The Maryland Biological Stream Survey (MBSS) currently uses validated Indices of Biological Integrity (IBIs) for fish (FIBI) and benthic macroinvertebrates (BIBI) to characterize the health of streams and rivers in the state. Both FIBI and BIBI have been used extensively, including incorporation as biocriteria by Maryland Department of the Environment, the agency responsible for water quality regulations in Maryland. In addition, a multimetric index for stream salamanders has been developed and tested but not yet applied. Although the ability of MBSS IBIs to discern between impaired and unimpaired streams was determined to be adequate for water quality management in Maryland, improvements may be possible that justify switching to a revised indicator or indicator suite. This paper will outline a current effort to evaluate changes to existing IBIs, including: tightening of reference criteria, development of specific coldwater and blackwater stream versions of the IBI, testing several new metrics, using continuous scoring for metrics, and changing to a 0 to 100 rating scale. Any revisions to IBIs will be considered within the context of costs such as recalculating scores for historical data, training partner agencies to use the new indicators, and outreach efforts to ensure acceptance.

Keywords: biological indicators; biocriteria applications; aquatic management; IBI

Improving Indicators for the Maryland Biological Stream Survey

Local Navigation