Macroinvertebrate Bioassessment Indices

NAMC uses observed to expected (O/E) and multimetric (MMI) indices to assess the biological condition of streams and rivers. We calculate both state-specific index and region-specific index scores as appropriate.

The state specific indices NAMC can apply include the following:

  1. Arizona Warm and Cold Water Indices of Biological Integrity
  2. Colorado Multimetric Index (all three biotypes)
  3. California Stream Condition Index
  4. Oregon Predator indices:
    1. Marine Western Coastal Forest
    2. Western Cordillera and Columbia Plateau
    3. Northern Basin and Range
  5. Utah Observed to Expected Index
  6. Wyoming Observed to Expected Index (all eleven bioregions)
  7. Nevada Multimetric Index (not used for regulatory purposes by the state)

Regional indices that NAMC can apply include the following:

  1. USFS PacFish InFish Biological Opinion (PIBO) Observed to Expected Index
  2. USFS Aquatic and Riparian Effectiveness Monitoring Program (AREMP)
    1. Observed to expected index
    2. Multimetric index
  3. Western Continental U.S. Observed to Expected Index
  4. Modeled Insect Richness Index (arid regions in western U.S.)

Requesting Index Calculation
To request the calculation of any of the above indices, ensure you make a note of which index you want calculated on submission of physical macroinvertebrate samples in the electronic submission interface accessed via the submit data button below.

If you have taxonomy data from another lab, we need sample collection data submitted via the electronic interface below as well as taxonomy and processing data.  You can find a description of sample collection data fields we need to ingest taxonomy data from outside laboratory and please send this info as an excel file to andrew.caudillo@usu.edu.
Submit Data

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