All males that approached the territory were confronted by the territorial male and chased from the area. Confrontations occurred every one to two minutes and increased while the male was courting a female. None has been reported. Okaloosa darters prefer stations where the vegetation is abundant. A minor peak in spawning takes place in September or October.
Males establish territories, and females are mated when they enter the territories.
The Okaloosa darter competes with, and may hybridize with, the brown darter, E. edwini. The two species were allopatric in distribution until relatively recently when brown darters began to appear in areas of Okaloosa darter distribution. The two species are now sympatric in two of the creeks inhabited by the Okaloosa darter. It is believed that human introduction may have caused the wider dispersal of E. edwini, although this cannot be established with certainty. U.S. Fish and Wildlife Service.