Evaluating a native fish species as an alternative to the western mosquitofish, Gambusia affinis, for the biological control of mosquitoes in southern California

The arroyo chub, Gila orcutti, is native to the watersheds of southern California and has been proposed as a replacement for the non-native western mosquitofish, Gambusia affinis, as a biological control agent for mosquitoes in sensitive watersheds throughout the region.  Because mosquito-eating fish are not strictly larvivorous, they also have the potential to impact non-target organisms in systems where they are introduced. The impact of arroyo chub stocking density on the invertebrate community and the suitability of a riverine constructed wetland as conservation habitat for the arroyo chub population in the Santa Ana River were evaluated at the Prado Wetlands in Riverside County, California.  Invertebrate abundance and community structure did not differ significantly among three stocking densities (0, 1.5 and 6 kg/ha) during a five-week study in cage mesocosms.