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

Tadpole Madtom Noturus gyrinus

Family
Ictaluridae (North American Catfishes)
Tolerance
Sensitive
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 44 bioassessment sites, 3 rapid fish bioassessment sites, 8 fisheries assessment sites, and 0 fisheries presence-only assessment sites. In total, it was collected at 54 distinct sites, or 3.6% of the 1513 total sites monitored by the bioassessment program. It is the 67th most commonly collected species.

The Tadpole Madtom was collected in 67 bioassessment sampling sessions and 9 fisheries assessment sessions. It was present in 3 rapid bioassessment sessions and 0 presence-only sessions.

The biological assessment program has collected a total of 219 individual Tadpole Madtom specimens, ranking it the #87 most collected fish.

Species Characteristics

Color varies from dark olive or brown to sometimes dark gray and light beneath. The head is large and fleshy and not flattened. The body is short and stout. It looks more like a bullhead than either of the other madtoms. There are 13 to 15, usually 14, rays in the anal fin. The premaxillary band is bar-shaped. There is a very narrow dark line along the side of the body. Upper and lower jaws are of equal length. This little fish rarely exceeds 3- or 4-inches long.

Species Distribution Maps

HUC12 watersheds where this species has been found