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

Brook Trout Salvelinus fontinalis

Salmonidae (Trouts)
Trophic Class
Top Carnivore
Is Exotic to Iowa?
Is Lithophilous Spawner?
Is Hybrid?
State Listing Status
Not Listed
Assessment Program Statistics

This species was found at 29 bioassessment sites, 0 rapid fish bioassessment sites, 53 fisheries assessment sites, and 0 fisheries presence-only assessment sites. In total, it was collected at 76 distinct sites, or 5.2% of the 1448 total sites monitored by the bioassessment program. It is the 59th most commonly collected species.

The Brook Trout was collected in 61 bioassessment sampling sessions and 99 fisheries assessment sessions. It was present in 0 rapid bioassessment sessions and 0 presence-only sessions.

The biological assessment program has collected a total of 2,938 individual Brook Trout specimens, ranking it the #46 most collected fish.

Species Characteristics

Brook Trout are easily recognized and distinguished from other trout by vivid white lines on the front or leading edge of the lower fins, and the top portion or back is covered with light wormy streaks or mottlings on a darker background called vermiculations. The dorsal fin has ten rays and is also strongly mottled. The vomer is trough-shaped, with the teeth restricted to the front portion. Brook trout feel soft to the touch because of the very small scales that cover the whole body. About 230 scales are along the lateral line, and they are more deeply embedded than other trout in the genus Salmo.

Species Distribution Maps

HUC12 watersheds where this species has been found