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

Spotted Bass Micropterus punctucatus

Centrarchidae (Sunfish)
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 2 bioassessment sites, 0 rapid fish bioassessment sites, 0 fisheries assessment sites, and 0 fisheries presence-only assessment sites. In total, it was collected at 2 distinct sites, or 0.1% of the 1442 total sites monitored by the bioassessment program. It is the 121st most commonly collected species.

The Spotted Bass was collected in 3 bioassessment sampling sessions and 0 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 6 individual Spotted Bass specimens, ranking it the #127 most collected fish.

Species Characteristics

A slender, streamlined-shaped sunfish with a large mouth, and the upper jaw extends slightly past the rear margin of the eye when the mouth is closed. The sides are greenish with darker mottlings and golden-shaded reflections. There is a broad dark continuous stripe along the side, but the margins of this stripe are noticeably more broken and uneven than in Largemouth Bass. This stripe may become unclear in large fish or in fish from turbid water. The lower sides have spots arranged in distinct rows that form a series of horizontal stripes. The tail fin in young bass has a black vertical bar that separates the yellowish-orange fin base from a whitish fringe along the rear margin of the fin. The dark bar usually forms a black spot in the middle of the tail fin. The pyloric caeca of Spotted Bass are not forked, like those of Smallmouth Bass.

Species Distribution Maps

HUC12 watersheds where this species has been found