Abstract

Gambusia affinis, also known as mosquitofish, is one of the most destructive invasive species.[1]  They were first introduced into environments to help reduce the mosquito population in places such as Australia, India and Louisiana.[2] Although research showed that the mosquito population did decline somewhat, Gambusia affinis caused a negative impact on the ecosystem. This was due to their high dispersal and fecundity rates, tolerance to a wide range of temperatures and salinities, and competitive behavior.[3] Compared to its less invasive relatives, Gambusia hispaniolae and Gambusia geiseri, Gambusia affinis is more aggressive, and has a high predatory behavior.[4] It out competes many native species such as least chubs (Iotichthys phlegethontis) and fathead minnows, by consuming their resources and attacking them.[5] Researchers are now trying to restore habitats to undisturbed conditions to favor the native species.[6]

[1] Ayala, J.R., Rader R.B., Belk, M.C., and Schaalje G.B. 2007. Ground-truthing the impact of invasive species: spatio-temporal overlap between native least chub and introduced western mosquitofish. Bio Invasions, Vol. 9: 857-869.

[2] Scientists provide mosquitofish to suppress New Orleans infestation. New Orleans CityBusiness. 2006.

[3] Rehage, J.S., Sih, A. 2004. Dispersal behavior, boldness, and the link to invasiveness: a comparison of four Gambusia species. Bio Invasions, Vol. 6: 379-391.

[4] Rehage, J.S., Barnett, B.K., and Sih, A. 2005. Behavioral responses to a novel predator and competitor of invasive mosquitofish and their non-invasive relatives. Behav Ecol Sociobiol, Vol. 57: 256-266.

[5] Ayala, J.R., Rader R.B., Belk, M.C., and Schaalje G.B. 2007. Ground-truthing the impact of invasive species: spatio-temporal overlap between native least chub and introduced western mosquitofish. Bio Invasions, Vol. 9: 857-869.

[6] Scoppettone, G.G., Rissler, P.H. Gourley, C., Martinez, C. 2005. Habitat restoration as a means of controlling non-native fish in a Mojave Desert oasis. Restoration Ecology, Vol. 13(2): 247-256.

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