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

Unnamed Tributary to Elk Creek Gillett Grove - Fen Valley WMA (HW116)

Fish Session #2390

Sample Date
8/8/2023
Timeframe
0853-0955  
Reach Size
594 ft
Method
Standard Wadeable
Sample Quality
Poor
Last Update
11/20/2025 9:40:48 AM

Fish Health

# DELTs
0
# Non-DELTs
0

Equipment

Backpack Shockers
1
Blocknets
1
Notice: This sampling session has not been through a Quality Assurance check and may contain errors. This notice will be removed once the QA has been completed.
Property Access Notice

This site is on public land, such as a county park, state park, or state-managed wildlife area.

FIBI Score
40
Warm Water
Fair
Session Comments

Heavy overhanging vegetation made walking and visibility while electroshocking extremely difficult. Fish voucher was sent to UI Natural History Museum.

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
Creek Chub
Latin: Semotilus atromaculatus
Family: Leuciscidae
Tolerance: Tolerant
Trophic: Generalist
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
77
Western Blacknose Dace
Latin: Rhinichthys obtusus
Family: Leuciscidae
Tolerance: Intermediate
Trophic: Insectivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
35
Brassy Minnow
Latin: Hybognathus hankinsoni
Family: Leuciscidae
Tolerance: Intermediate
Trophic: Herbivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
5
Common Shiner
Latin: Luxilus cornutus
Family: Leuciscidae
Tolerance: Intermediate
Trophic: Insectivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
3
Bluntnose Minnow
Latin: Pimephales notatus
Family: Leuciscidae
Tolerance: Tolerant
Trophic: Omnivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
3
Brook Stickleback
Latin: Culaea inconstans
Family: Gasterosteidae
Tolerance: Sensitive
Trophic: Insectivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
2
Fathead Minnow
Latin: Pimephales promelas
Family: Leuciscidae
Tolerance: Tolerant
Trophic: Omnivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
1
Banded Killifish
Latin: Fundulus diaphanus
Family: Fundulidae
Tolerance: Intermediate
Trophic: Insectivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
1
Johnny Darter
Latin: Etheostoma nigrum
Family: Percidae
Tolerance: Intermediate
Trophic: Benthic Invertivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
1

FIBI Calculation Factors

Factor Value
Drainage area (mi2) 3.5130
Log(DA) 0.5457
Total Fish 128
Fish per 500 ft 108
Total Species 9
# Excluded Taxa 0
# Exotic Species 0
# LMB-BG 0
Calculation Last Updated 11/20/2025 9:40:48 AM

Fish Index of Biotic Integrity

Metric Name Value Score
Native Species 9 10
Sucker Species 0 0
Sensitive Species 1 10
Benthic Invertivore Species 1 5.89
Top 3 Abundance Percentage 91.41 4.04
Benthic Invertivore Percentage 0.78 0.6
Omnivore Percentage 3.12 10
Top Carnivore Percentage 0 0
Lithophilous Spawner Percentage 0 0
Tolerance Index 8.09 3.03
Adjusted Catch per Unit Effort 7.91 0.79
DELT Percentage Adjustment 0 0

FIBI Score Explained

Sites that score between 26 - 50 are considered fair. Fish abundance ranges from lower than average to very abundant. If fish are abundant, tolerant species are usually dominant. Native fish species usually equal ten or more species. The three most abundant species typically comprise two-thirds or more of the total number of fish. One or more sensitive species, long-lived fish species or benthic habitat specialists such as suckers (Catostomidae) are present. Top carnivore species are often, but not always present in low abundance. Species that are able to utilize a wide range of food items including plant, animal and detritus are usually more common than specialized feeders, such as benthic invertivore fish. Species that require silt-free, rock substrate for spawning or feeding are typically rare or absent. Fish condition is usually good; however, elevated levels of fish exhibiting external anomalies associated with disease or stress are not unusual.

This location has been classified as a Candidate Reference Site. Further study is required to determine if this site represents natural stream qualities that are least disturbed by human activities within the watershed.

EcoRegion Comparison

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

Des Moines Lobe

This site is in the Des Moines Lobe ecoregion.

Ecoregion Map
Max 85
75th Percentile 62
Median 51
25th Percentile 38
Min 13
This Session's Score 40
Total Reference Site Samples 125
Mean 50.2
Standard Deviation 15.93