The Benthic Macroinvertebrate Index of Biotic Integrity (BM-IBI) is a composite index of 12 individual metrics that provide an assessment of stream biological community integrity. 

A metric is an attribute or characteristic of the aquatic community that is quantifiable and has ecological relevance.  Useful metrics share the following characteristics: a) measured relatively easily and economically; b) exhibit relatively low natural variability; c)  respond predictably to changes in stream quality; d) do not duplicate information supplied by other metrics.

Iowa DNR BMIBI Types

• BMIBI-Warm Water
• BMIBI-Cold Water