2012 Training Program - Segment 3
Benthic Macroinvertebrates & Stream Health



Small watercourses, such as streams, are homes to lots of tiny animals that live on and under the rocks, on the water plants, or on bits of wood lying in the stream. These animals include larval insects, clams, mussels, worms, and leeches. Collectively they are called macroinvertebrates - animals without backbones - and can be seen with the naked eye. Macroinvertebrates are a good indicator of stream health. An experienced biologist, with only a cursory examination of the macroinvertebrate assemblage, can determine the site-specific conditions of a stream. The Rapid Bioassessment (RBA) has become one of the standard methods to gather such biological data.


This training segment provided participants with a discussion, including identification, of stream macroinvertebrates; a review of the RBA method; a hands-on exercise to identify organisms and determine the health of a hypothetical stream; and ended with an optional field stream survey demonstration.

Background Materials

water insect on a leaf
Classroom Presentations
Supplemental Training Materials

Content Last Updated March 17, 2020.