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

East Fork Unnamed Tributary To Arbor Lake Grinnell

Fish Session #575

Sample Date
10/10/2003
Timeframe
10:20-11:05  
Reach Size
455 ft
Method
Standard Wadeable
Sample Quality
Fair
Last Update
10/1/2004 12:00:00 AM

Fish Health

# DELTs
0
# Non-DELTs
0

Equipment

Backpack Shockers
1
Blocknets
0
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
0
Warm Water
Poor
Session Comments

There was some blue green algae on the surface of the water at the lower reach; in addition, there was a significant amount of leaves on the surface as well.

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
Largemouth Bass
Latin: Micropterus nigricans
Family: Centrarchidae
Tolerance: Intermediate
Trophic: Top Carnivore-LMB Exclusion
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
9
Bluegill
Latin: Lepomis macrochirus
Family: Centrarchidae
Tolerance: Intermediate
Trophic: Insectivore
Is Exotic: False
Is LithoSpawner: False
Is Hybrid: False
4

FIBI Calculation Factors

Factor Value
Drainage area (mi2) 0.3090
Log(DA) 0.0001
Total Fish 13
Fish per 500 ft 14
Total Species 2
# Excluded Taxa 0
# Exotic Species 0
# LMB-BG 2
Calculation Last Updated 2/7/2025 2:34:38 PM

Fish Index of Biotic Integrity

Metric Name Value Score
Native Species 0 0
Sucker Species 0 0
Sensitive Species 0 0
Benthic Invertivore Species 0 0
Top 3 Abundance Percentage 100 0
Benthic Invertivore Percentage 0 0
Omnivore Percentage 0 0
Top Carnivore Percentage 0 0
Lithophilous Spawner Percentage 0 0
Tolerance Index 5 0
Adjusted Catch per Unit Effort 2.86 0.29
DELT Percentage Adjustment 0 0

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:

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 0
Total Reference Site Samples 105
Mean 49.02
Standard Deviation 14.97