Shell Rock River Rockford Impoundment (SH005)
Fish Session #80
- Sample Date
- 8/14/2013
- Timeframe
- 78.4
- Reach Size
- 3884 ft
- Method
- Fisheries Non-wadeable
- Sample Quality
- Good
- Last Update
- 10/31/2015 11:57:04 AM
This site is on privately-owned land. The DNR obtains permission from the landowner(s) prior to conducting any sampling surveys.
Warm Water
Poor
Water Temp 73 F, Secchi 17", Conductivity 520. No suitable habitat for supplemental probe shocking.
- Identity verification status for this species
- Morphometrics: Length/Weight measurements of individual specimens
- Taxa excluded from species count metrics.
- Click on species name for more information about that species
| Species | Catch | |
|---|---|---|
|
Bigmouth Buffalo
Latin: Ictiobus cyprinellus
Family: Catostomidae Tolerance: Intermediate Trophic: Insectivore Is Exotic: False Is LithoSpawner: False Is Hybrid: False |
61 | |
|
Common Carp
Latin: Cyprinus carpio
Family: Cyprinidae Tolerance: Tolerant Trophic: Omnivore Is Exotic: True Is LithoSpawner: False Is Hybrid: False |
33 | |
|
Quillback Carpsucker
Latin: Carpiodes cyprinus
Family: Catostomidae Tolerance: Intermediate Trophic: Omnivore Is Exotic: False Is LithoSpawner: False Is Hybrid: False |
14 | |
|
Silver Redhorse
Latin: Moxostoma anisurum
Family: Catostomidae Tolerance: Intermediate Trophic: Benthic Invertivore Is Exotic: False Is LithoSpawner: True Is Hybrid: False |
13 | |
|
Common Shiner
Latin: Luxilus cornutus
Family: Leuciscidae Tolerance: Intermediate Trophic: Insectivore Is Exotic: False Is LithoSpawner: False Is Hybrid: False |
11 | |
|
Smallmouth Bass
Latin: Micropterus dolomieu
Family: Centrarchidae Tolerance: Sensitive Trophic: Top Carnivore Is Exotic: False Is LithoSpawner: False Is Hybrid: False |
3 | |
|
Largemouth Bass
Latin: Micropterus nigricans
Family: Centrarchidae Tolerance: Intermediate Trophic: Top Carnivore-LMB Exclusion Is Exotic: False Is LithoSpawner: False Is Hybrid: False |
3 | |
|
Shorthead Redhorse
Latin: Moxostoma macrolepidotum
Family: Catostomidae Tolerance: Intermediate Trophic: Benthic Invertivore Is Exotic: False Is LithoSpawner: True Is Hybrid: False |
1 | |
|
Spotfin Shiner
Latin: Cyprinella spiloptera
Family: Leuciscidae Tolerance: Intermediate Trophic: Insectivore Is Exotic: False Is LithoSpawner: False Is Hybrid: False |
1 | |
|
Yellow Bullhead
Latin: Ameiurus natalis
Family: Ictaluridae Tolerance: Intermediate Trophic: Benthic Invertivore Is Exotic: False Is LithoSpawner: False Is Hybrid: False |
1 | |
FIBI Calculation Factors
| Factor | Value |
|---|---|
| Drainage area (mi2) | 529.0000 |
| Log(DA) | 2.7235 |
| Total Fish | 141 |
| Fish per 500 ft | 18 |
| Total Species | 10 |
| # Excluded Species | 0 |
| # Exotic Species | 1 |
| # LMB-BG | 1 |
| Calculation Last Updated | 10/29/2025 12:38:40 PM |
Fish Index of Biotic Integrity
| Metric Name | Value | Score |
|---|---|---|
| Native Species | 8 | 2.29 |
| Sucker Species | 4 | 5 |
| Sensitive Species | 1 | 0.83 |
| Benthic Invertivore Species | 3 | 2.5 |
| Top 3 Abundance Percentage | 76.6 | 0 |
| Benthic Invertivore Percentage | 10.64 | 0 |
| Omnivore Percentage | 33.33 | 0 |
| Top Carnivore Percentage | 2.13 | 0 |
| Lithophilous Spawner Percentage | 9.93 | 0 |
| Tolerance Index | 6.06 | 0 |
| Adjusted Catch per Unit Effort | 2.78 | 0.28 |
| DELT Percentage Adjustment | 0 | 0 |
The Fish Index of Biotic Integrity for Large River sampling sessions is currently calculated using the standard wadeable stream FIBI metrics. The IBI scores for Large River sessions are typically lower than those calculated for wadeable streams, but are included for comparison purposes.
Large Rivers score lower due to the difficulty of sampling deep rivers. Boat shockers are also selective towards larger fish species, as it is more difficult to collect smaller fish species, such as minnows, in the deeper water.
FIBI Score Explained
Sites that score between 0 - 25 are considered poor. Fish abundance is usually lower than normal or, if fish are abundant, the collection is dominated by a few tolerant species. The number of native fish species present is low. Sensitive species and habitat specialists are absent or extremely rare. The population is dominated by just a few ubiquitous species that are tolerant of wide-ranging water quality and habitat conditions. Pioneering, introduced and/or short-lived fish species are typically the most abundant types of fish. Fish collected at poor sites often have a higher than normal occurrence of external physical anomalies.
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:
| Max | 92 |
| 75th Percentile | 77 |
| Median | 70 |
| 25th Percentile | 60 |
| Min | 27 |
| This Session's Score | 10 |
| Total Reference Site Samples | 140 |
| Mean | 67.94 |
| Standard Deviation | 13.97 |