SREL Reprint #1811

Management of indigenous fish species impacted by introduced mosquitofish: an experimental approach

Charles Lydeard and Mark C. Belk

University of Georgia's Savannah River Ecology Laboratory, Drawer E, Aiken, SC 29802

Abstract: The negative effects of introduced mosquitofish (Gambusia affinis) on native fishes of the American Southwest have been well documented. However, little experimental information is available to determine the level to which populations of Gambusia must he reduced before reintroducing native species. To simulate various options for managing indigenous fishes impacted by mosquitofish, we observed population growth of the least killifish (Heterandria formosa) with different starting densities of the eastern mosquitofish (Gambusia holbrooki) in replicate mesocosms. The presence of mosquitofish at all densities examined had a significant negative effect on population growth of least killifish. Therefore, complete removal of introduced mosquitofish appears to be the best management option for maintaining populations of native fishes.

SREL Reprint #1811

Lydeard, C. and M.C. Belk. 1993. Management of indigenous fish species impacted by introduced mosquitofish: an experimental approach. The Southwestern Naturalist 38:370-373.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).