Iowa DNR
BioNet
River & Stream Biological Monitoring
Fish and Benthic Macroinvertebrate Surveys
Physical Habitat Assessments

Silver Creek Dewitt

Fish Session #1446

Sample Date
7/17/2012
Timeframe
1000-1120  
Reach Size
956 ft
Method
Standard Wadeable
Sample Quality
Good
Last Update
11/4/2013 10:17:35 AM

Fish Health

# DELTs
0
# Non-DELTs
0

Equipment

Backpack Shockers
0
Blocknets
1
Barge Shocker
True
Property Access Notice

This site is on privately-owned land. The DNR obtains permission from the landowner(s) prior to conducting any sampling surveys.

FIBI Score
57
Warm Water
Good
Session Comments

No comments recorded.

Collected Fish

Identity verification status for this species
Size Class: Typically only collected for sportfish
Taxa excluded from species count metrics.
Click on species name for more information about that species
Species Catch
White Sucker
Latin: Catostomus commersonii
Family: Catostomidae
Tolerance: Intermediate
Trophic: Omnivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
210
Mississippi Silvery Minnow
Latin: Hybognathus nuchalis
Family: Leuciscidae
Tolerance: Sensitive
Trophic: Omnivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
167
Fantail Darter
Latin: Etheostoma flabellare
Family: Percidae
Tolerance: Intermediate
Trophic: Benthic Invertivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
135
Common Shiner
Latin: Luxilus cornutus
Family: Leuciscidae
Tolerance: Intermediate
Trophic: Insectivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
68
Creek Chub
Latin: Semotilus atromaculatus
Family: Leuciscidae
Tolerance: Tolerant
Trophic: Generalist
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
61
Western Blacknose Dace
Latin: Rhinichthys obtusus
Family: Leuciscidae
Tolerance: Intermediate
Trophic: Insectivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
48
Central Stoneroller
Latin: Campostoma anomalum
Family: Leuciscidae
Tolerance: Intermediate
Trophic: Herbivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
34
Green Sunfish
Latin: Lepomis cyanellus
Family: Centrarchidae
Tolerance: Tolerant
Trophic: Generalist
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
28
Bluntnose Minnow
Latin: Pimephales notatus
Family: Leuciscidae
Tolerance: Tolerant
Trophic: Omnivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
24
Spotfin Shiner
Latin: Cyprinella spiloptera
Family: Leuciscidae
Tolerance: Intermediate
Trophic: Insectivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
18
Johnny Darter
Latin: Etheostoma nigrum
Family: Percidae
Tolerance: Intermediate
Trophic: Benthic Invertivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
17
Longnose Dace
Latin: Rhinichthys cataractae
Family: Leuciscidae
Tolerance: Sensitive
Trophic: Benthic Invertivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
15
Smallmouth Bass
Latin: Micropterus dolomieu
Family: Centrarchidae
Tolerance: Sensitive
Trophic: Top Carnivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
11
Largemouth Bass
Latin: Micropterus nigricans
Family: Centrarchidae
Tolerance: Intermediate
Trophic: Top Carnivore-LMB Exclusion
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
5
Bigmouth Shiner
Latin: Ericymba dorsalis
Family: Leuciscidae
Tolerance: Tolerant
Trophic: Insectivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
3
Bluegill
Latin: Lepomis macrochirus
Family: Centrarchidae
Tolerance: Intermediate
Trophic: Insectivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
3
Brassy Minnow
Latin: Hybognathus hankinsoni
Family: Leuciscidae
Tolerance: Intermediate
Trophic: Herbivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
2
Golden Redhorse
Latin: Moxostoma erythrurum
Family: Catostomidae
Tolerance: Intermediate
Trophic: Benthic Invertivore
Is Exotic: False
Is LithoSpawner: True
Is Hybrid: False
2
Hornyhead Chub
Latin: Nocomis biguttatus
Family: Leuciscidae
Tolerance: Sensitive
Trophic: Insectivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
1
Pumpkinseed
Latin: Lepomis gibbosus
Family: Centrarchidae
Tolerance: Intermediate
Trophic: Insectivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
1
Black Bullhead
Latin: Ameiurus melas
Family: Ictaluridae
Tolerance: Tolerant
Trophic: Generalist
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
1
Banded Darter
Latin: Etheostoma zonale
Family: Percidae
Tolerance: Sensitive
Trophic: Benthic Invertivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
1
Blackside Darter
Latin: Percina maculata
Family: Percidae
Tolerance: Sensitive
Trophic: Benthic Invertivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
1

FIBI Calculation Factors

Factor Value
Drainage area (mi2) 35.9230
Log(DA) 1.5554
Total Fish 856
Fish per 500 ft 448
Total Species 23
# Excluded Taxa 0
# Exotic Species 0
# LMB-BG 2
Calculation Last Updated 2/7/2025 2:32:20 PM

Fish Index of Biotic Integrity

Metric Name Value Score
Native Species 21 8.1
Sucker Species 2 3.94
Sensitive Species 6 6.76
Benthic Invertivore Species 6 6.43
Top 3 Abundance Percentage 59.81 6.63
Benthic Invertivore Percentage 19.98 5.39
Omnivore Percentage 46.85 4.38
Top Carnivore Percentage 1.29 4.13
Lithophilous Spawner Percentage 0.23 0.12
Tolerance Index 4.54 8.67
Adjusted Catch per Unit Effort 77.3 7.73
DELT Percentage Adjustment 0 0

FIBI Score Explained

Sites that score between 51 - 70 are considered good. Fish (excluding tolerant species) are fairly abundant to very abundant. If high numbers are present, intermediately tolerant species or tolerant species are usually dominant. A moderately high number of fish species belonging to several families are present. The three most abundant fish species typically comprise two-thirds or less of the total number of fish. Several long-lived species and benthic invertivore species are present. One or more sensitive species are usually present. Top carnivore species are usually present in low numbers and often one or more life stages are missing. Species that require silt-free, rock substrate for spawning or feeding are present in low proportion to the total number of fish. Fish condition is good; typically less than 1% of the total number of fish exhibits external anomalies associated with disease or stress.

This location has been classified as a Reference Site. Reference sites represent natural stream qualities that are least disturbed by human activities within the watershed. These sites are then grouped by ecoregion to establish a benchmark against which other streams in the same ecoregion are compared.

EcoRegion Comparison

Scores for a sampling session are compared against reference sites within the same ecoregion:

Rolling Loess Prairies

This site is in the Rolling Loess Prairies ecoregion.

Ecoregion Map
Max 83
75th Percentile 59
Median 48
25th Percentile 38
Min 10
This Session's Score 57
Total Reference Site Samples 105
Mean 49.02
Standard Deviation 14.97