Predators’ size influences life history traits of Aedes aegypti

Abstract

Predator-prey relationships are not limited to predation. A predator may release chemical cues that may directly affect the physiology and behavior of a prey by fear and intimidation. Our objective was testing the effect of the body size of predator (dragonfly larvae) on the larval development time and mortality, as also, on the survival, wing asymmetry and adult size of Ae. aegypti. Using a microcosm set-up, we simulated the predation risk by dragonflies (Odonata, Libelulidae family) over Aedes aegypti. Microcosms consisted of 40 larvae of Ae. aegypti under the indirect effect of predators with different body sizes (four treatments comprising different body size classes; n = 5 per treatment). We found that intermediate-sized predators had the highest effects on the mosquito's life history traits. Predator presence increased prey larval mortality (±150%) and accelerated development times (±33%), and reduced adult body size (± 24%) and survival (56%). On the other hand, no change in asymmetries of wings size was observed in Ae. aegypti mosquitoes. Therefore, our results support that both predator presence and size are responsible for changes in Ae. aegyptitraits during the larval and adult stages.