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

Johnny Darter Etheostoma nigrum

Family
Percidae (Perches)
Tolerance
Intermediate
Trophic Class
Benthic Invertivore
Is Exotic to Iowa?
False
Is Lithophilous Spawner?
False
Is Hybrid?
False
State Listing Status
Not Listed
Assessment Program Statistics

This species was found at 633 bioassessment sites, 127 rapid fish bioassessment sites, 101 fisheries assessment sites, and 27 fisheries presence-only assessment sites. In total, it was collected at 805 distinct sites, or 59.6% of the 1350 total sites monitored by the bioassessment program. It is the 4th most commonly collected species.

The Johnny Darter was collected in 1318 bioassessment sampling sessions and 285 fisheries assessment sessions. It was present in 127 rapid bioassessment sessions and 30 presence-only sessions.

The biological assessment program has collected a total of 47,936 individual Johnny Darter specimens, ranking it the #11 most collected fish.

Species Characteristics

A small member of the darters, reaching a maximum of about 2 1/2-inches long. It is olive in color with numerous, conspicuous w-shaped markings along the sides. The dorsal fin has 12 rays, the anal has 8 rays; there are usually about 50 scales along the lateral line, and the breast and cheeks are scaleless.

Species Distribution Maps

HUC12 watersheds where this species has been found