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Tadpole madtom

Tadpole madtom


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.


Tadpole madtom Distribution

Widely distributed in the large interior rivers and the Mississippi River; most abundant in the small, rocky, clear-water streams, mainly in the northeastern and northcentral regions. Its presence in many of the oxbow lakes along the Missouri River shows that it also lives in the parent stream. Occasionally taken in natural and man-made Iowa lakes.


Insects, occasionally algae and other aquatic plants

State Record

State Records are not documented for non-game species.

Expert Tip



Female madtoms usually mate several times during the June through July breeding period. Young fish have been taken in collections in late fall measuring about one inch long. Most fish probably mature during their second summer, and few live beyond their third summer.

Like most madtoms, this species is most active at night. These catfish, as well as the other madtoms, have a poison gland at the base of the pectoral fin. When one is stung or pricked by one of the spines, there is a burning sensation similar to a bee or wasp sting.

Recent stream sampling information is available from Iowa DNR's biological monitoring and assessment program.


Present in these Iowa water bodies:

Lake/Stream County Location Acres/Length
Clear Lake Cerro Gordo south edge of Clear Lake 3684.00
Missouri River (Sioux City to Little Sioux) Harrison Chris Larsen Park: 1280 Larsen Park Road/Sioux City, IA. Located on the Sioux City riverfront along the Missouri River. Larsen Park offers 110 acres on the Sioux City Riverfront. Managed by the City of Sioux City. 64.00
Missouri River (Council Bluffs to state line) Fremont Lake Manawa State Park: 1100 South Shore Drive/Council Bluffs, IA 51501 phone: 712-366-0220. Managed by the Iowa Department of Natural Resources Lake Manawa State Park has boat ramps on the Missouri River within the park. 61.00
Missouri River (Little Sioux to Council Bluffs) Pottawattamie Wilson Island State Recreation Area: 32801 Campground Lane/Missouri Valley, IA 51555 phone-712-642-2069. Managed by the Iowa Department of Natural Resources, Wilson Island Recreation Area has 544 acres along the Missouri River near Missouri Valley Iowa. 53.00