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

Mottled Sculpin Cottus bairdii

Cottidae (Sculpins)
Trophic Class
Benthic Invertivore
Is Exotic to Iowa?
Is Lithophilous Spawner?
Is Hybrid?
State Listing Status
Not Listed
Assessment Program Statistics

This species was found at 7 bioassessment sites, 1 rapid fish bioassessment site, 0 fisheries assessment sites, and 1 fisheries presence-only assessment site. In total, it was collected at 8 distinct sites, or 0.6% of the 1281 total sites monitored by the bioassessment program. It is the 102nd most commonly collected species.

The Mottled Sculpin was collected in 12 bioassessment sampling sessions and 0 fisheries assessment sessions. It was present in 1 rapid bioassessment session and 1 presence-only session.

The biological assessment program has collected a total of 488 individual Mottled Sculpin specimens, ranking it the #71 most collected fish.

Species Characteristics

The head and anterior body is flattened dorso-ventrally with the posterior body and caudal peduncle compressed laterally. The mouth is terminal and has numerous teeth in narrow bands on both jaws. It has two dorsal fins that are narrowly connected; the first has 6 to 9 soft spines and the second has 17 to 19 rays. The anal fin has 13 to 15 rays, the pelvic fin is thoracic with one spine and 4 rays, and the pectoral fin has 14 to 15 rays. Scales are absent along the incomplete lateral line ending under the second dorsal fin. The back and sides are brown to tan with dark mottling, and the lower region of the head and belly are whitish. This fish averages 3- to 4-inches long.

Species Distribution Map