West Fork Little Sioux River Hornick
Analysis Summary for Series #1354
Benthic Macroinvertebrate Index of Biotic Integrity (BMIBI)
| Metric Name | Value | Score |
|---|---|---|
| MH Total Taxa | 23 | 4.42 |
| SH Total Taxa | 7.67 | 3.38 |
| MH EPT Taxa | 7 | 2.59 |
| SH EPT Taxa | 5 | 3.4 |
| MH Sensitive Taxa | 2 | 1.82 |
| SH Ephem % | 3.67 | 0.47 |
| SH EPT % | 32.22 | 3.37 |
| SH Chiron % | 65.04 | 3.53 |
| SH Scraper % | 0 | 0 |
| SH Top3Dom % | 89.43 | 1.68 |
| SH Dom FFG % | 69.59 | 5.07 |
| MHBI | 5.76 | 4.59 |
| *Mouse-over metric for full name | ||
| **Final IBI is sum of scores multiplied by 0.8333 | ||
Analysis Factors
| Factor | Value |
|---|---|
| BMIBI Type | Warm Water |
| Sample Date | 9/5/2012 |
| Sampling Series | Series #1354 |
| Drainage Area (mi2) | 399 |
| Log(DA) | 2.60097289568675 |
| Calculation Last Updated | 7/22/2025 3:35:25 PM |
| Sampling Gear | ArtSub |
Sessions used in this analysis
Warm Water
Poor
BMIBI Score Explained
This site was analyzed using the BMIBI-Warm Water assessment methodology.
Sites that score between 0 - 30 are considered poor. Severely impaired macroinvertebrate community. Low numbers of taxa present, sensitive species not present, EPT taxa are rare or not present; community extremely unbalanced; dominated by a few pollution tolerant organisms; some trophic functional feeding groups are not represented. Total numbers of organisms may be low. Total taxa richness and EPT taxa richness are noticeably reduced from optimum levels; sensitive species and habitat specialists are rare; EPT taxa no longer dominate the macroinvertebrate community. Taxa that are tolerant of organic enrichment and/or excessive sediment loads are dominant; the community is unbalanced; a few generalist taxa make up a high percentage of the organisms present; collector-gatherers or collector-filterers are very dominant.
This location has been classified as a survey site. Survey sites are compared to reference sites within the same ecoregion. A reference site represents natural stream qualities that are least disturbed by human activities within the watershed. Reference sites are grouped by ecoregion to establish a benchmark against which these survey streams are compared.
EcoRegion Comparison
Scores for a sampling session are compared against reference sites within the same ecoregion:
There are not enough sampling sessions collected at reference sites in this ecoregion to generate a meaningful comparison.