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Maryland Streams – Teaching Resources

(1) Biological Assessment of Stream Health

Click here for Overall Student Data Sheet for All Stream Activities

Looking at biological indicators of stream quality is different for freshwater and saltwater habitats.

For freshwater streams– macroinvertebrates as indicators

Conducting a biological assessment involves capturing and identifying macroinvertebrates (aquatic insects and their larvae, and more), which serve as indicators of the health of freshwater streams. Macroinvertebrates are part of the aquatic food web, are easy to collect without expensive equipment and provide information about the quality of a stream over long periods of time. Data obtained by macroinvertebrate sampling can indicate the need for additional data collection, such as water chemistry analysis. Different living indicators are needed for streams that have brackish or salt water.

Recommended reference with background ecology information and field guide: Voshell,Jr., J. Reese. A Guide to Freshwater Invertebrates of North America. Mc Donald & Woodward Publishing Co. Blacksburg, VA. 2002.

For brackish or salt water streams and creeks