Micropterus coosae

Redeye bass

Family: Centrarchidae · Class: Actinopterygii · Order: Perciformes

The redeye bass (Micropterus coosae) is a freshwater game fish in the sunfish family Centrarchidae, native to the southeastern United States. Adults typically measure 203 to 305 mm (8 to 12 inches) in total length and weigh 0.23 to 0.68 kg (0.5 to 1.5 pounds). The species exhibits a compressed, elongated body with a bronze to golden-brown coloration on the dorsal surface, transitioning to pale yellow or white on the ventral region. The distinguishing characteristic is the bright red or orange coloration of the iris, giving the species its common name. Dark vertical bars are present along the sides, particularly prominent in juveniles, and a distinctive dark spot marks the posterior edge of the operculum. Redeye bass are indigenous to the southeastern United States, with their native range encompassing river systems from Georgia and South Carolina west to eastern Tennessee and Alabama. The species naturally occurs in the Tennessee River drainage, Savannah River system, and several smaller Atlantic coastal drainages. In California, redeye bass are not native and are considered an introduced species, though their current distribution and establishment status in the state requires verification from recent surveys. The species inhabits flowing waters including small to medium-sized streams, rivers, and rocky creeks. Redeye bass prefer clear, cool waters with rocky or gravel substrates and moderate to swift current. Adults are typically found in deeper pools and eddies near cover such as fallen timber, undercut banks, or large boulders. Water temperatures between 16 to 24 degrees Celsius (60 to 75 degrees Fahrenheit) are optimal for the species. Elevation preferences in native habitats range from near sea level to approximately 610 meters (2,000 feet). Redeye bass are carnivorous, feeding primarily on aquatic insects, crayfish, and smaller fish including minnows and juvenile sunfish. Adults also consume terrestrial insects that fall into the water. Spawning occurs from April through June when water temperatures reach 16 to 21 degrees Celsius (60 to 70 degrees Fahrenheit). Males construct circular nests in gravel or sand substrates in shallow areas with moderate current. Females deposit 2,000 to 10,000 adhesive eggs, which are fertilized and guarded by males until hatching occurs after 3 to 5 days. Sexual maturity is reached at 2 to 3 years of age. Redeye bass are not federally listed under the Endangered Species Act and appear to have no special conservation status in California as of December 2025. In their native southeastern range, populations remain stable, though some local declines have occurred due to habitat modification and water quality degradation. As a non-native species in California, redeye bass may compete with native fish species for habitat and food resources. Management considerations include monitoring their distribution and potential impacts on endemic California fish communities, particularly in stream systems where they may overlap with sensitive native species.

Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, and more.