Hunger-dependent and sex-specific antipredator behavior of Aedes triseriatus

Modification of behaviors in the presence of predators or predation cues is widespread among animals. Costs of this behavioral change depend on fitness effects of lost feeding opportunities and, especially when organisms are sexually dimorphic in size or timing of maturation, these costs are expected to differ between the sexes. Larval Aedes triseriatus were used to test the hypothesis that behavioral responses of the sexes have been selected differently due to different energy demands. Even in the absence of water-borne predation cues, hungry females spent more time browsing than males, indicative of a difference in energy needs. In the presence of predation cues, well-fed larvae of both sexes reduced their activity more than do hungry larvae, and males shifted away from high-risk behaviors to a greater degree than did females. Because sexual dimorphism is common, and energetic demands are likely correlated with dimorphism, this research underlines the importance of investigating sex specific behavior and behavioral responses to enemies and cautions against generalizing results between sexes.