Predation by a cyprinodontid fish, Aphanius mento, on Culex pipiens: effects of alternative prey and vegetation.

We assessed the effects of an alternative prey species (Daphnia magna) and a submergent plant (Ceratophyllum demersum) on the efficiency of the fish, Aphanius mento, to prey on mosquito (Culex pipiens) larvae in the laboratory. Aphanius mento is an untested biological control candidate of mosquitoes. When D. magna was introduced with equal numbers of Cx. pipiens larvae, there was a 50.7% reduction in predation by A. mento on the mosquito larvae. However, the more D. magna a fish ate, the more Cx. pipiens it consumed. Ceratophyllum demersum did not affect predation rates on Cx. pipiens larvae.