Both consumptive and non-consumptive effects of predators impact mosquito populations and have implications for disease transmission

Russell, M. C.; Herzog, C. M.; Gajewski, Z.; Ramsay, C.; El Moustaid, F.; Evans, M. V.; Desai, T.; Gottdenker, N.; Hermann, S.; Power, A. G.; McCall, A. C.

doi:10.1101/2021.07.31.454599

bioRxiv · 10.1101/2021.07.31.454599

Both consumptive and non-consumptive effects of predators impact mosquito populations and have implications for disease transmission

Russell, M. C.·Herzog, C. M.·Gajewski, Z.·Ramsay, C.·El Moustaid, F.·Evans, M. V.·Desai, T.·Gottdenker, N.·Hermann, S.·Power, A. G.·McCall, A. C.

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Abstract

Predator-prey interactions influence prey traits through both consumptive and non-consumptive effects, and variation in these traits can shape vector-borne disease dynamics. Meta-analysis methods were employed to generate predation effect sizes by different categories of predators and mosquito prey. This analysis showed that multiple families of aquatic predators are effective in consumptively reducing mosquito survival, and that the survival of Aedes, Anopheles, and Culex mosquitoes is negatively impacted by consumptive effects of predators. Mosquito larval size was found to play a more important role in explaining the heterogeneity of consumptive effects from predators than mosquito genus. Mosquito survival and body size were reduced by non-consumptive effects of predators, but development time was not significantly impacted. In addition, Culex vectors demonstrated predator avoidance behavior during oviposition. The results of this meta-analysis suggest that predators limit disease transmission by reducing both vector survival and vector size, and that associations between drought and human West Nile virus cases could be driven by the vector behavior of predator avoidance during oviposition. These findings are likely to be useful to infectious disease modelers who rely on vector traits as predictors of transmission.

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Russell, M. C., Herzog, C. M., Gajewski, Z., Ramsay, C., El Moustaid, F., Evans, M. V., Desai, T., Gottdenker, N., Hermann, S., Power, A. G., McCall, A. C.. 2021-08-02. Both consumptive and non-consumptive effects of predators impact mosquito populations and have implications for disease transmission. https://doi.org/10.1101/2021.07.31.454599

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