Fish microbiota repels ovipositing mosquitoes

Abstract

The mere presence of predators causes prey organisms to enact predation-avoidance strategies. This presence is often revealed through predator-released kairomones. It was previously suggested that in many cases, the predator microbiota composition plays an essential role in releasing these kairomones, however, this mechanism is still poorly understood. Ovipositing mosquito females of several species are repelled by kairomones released from larvivorous fish. In this study, we looked into the effects of the microbiota originated by Gambusia affinis (Baird and Girard) on the oviposition behavior of gravid mosquito females in an outdoor mesocosm experiment. We show that interference with the fish microbiota significantly reduces its repellant effect. We further show that the bacterium Pantoea pleuroti isolated from the skin of the fish repels oviposition of Culex laticinctus (Edwards) and Culiseta longiareolata Macquart mosquitoes similarly to the effect of live fish. These results highlight the importance of bacteria in the interspecies interactions of their hosts and the potential conflict of interest in this system, where bacteria may benefit from the absence of the bacterivore mosquito larvae, but the fish lose access to prey.

Fish microbiota repel ovipositing mosquitoes

“…Data are available from the Dryad Digital Repository: https://doi.org/10.5061/dryad.9p8cz8wqf (Shteindel et al., 2024).…”