The alien smallmouth bass was uncommon at the detox site before treatment. The first year after treatment two adults and a large number of young-of-the-year fish were present. Smallmouths continued to dominate the site through the drought years, contributing 80 percent of the total biomass in several years and may have been a major deterrent to the recovery of native fishes. In 1996 through 1998, their population seems somewhat depressed, probably as a result of the winter high flows.