Sphaerophoria rueppelli adults change their foraging behavior after mating but maintain the same preferences to flower traits

Abstract

Hoverflies can play an important role in aphid biological control. Adult hoverflies depend on pollen and nectar to survive. Therefore the placement of flower resources in agroecosystems is a common method to enhance the populations of these insects.When foraging, hoverflies rely on visual cues to select flowers. We studied the preference of Sphaerophoria rueppelli (Wiedemann) (Diptera: Syrphidae) adults for several flower traits and examined whether mating influenced foraging behavior. We observed that these insects were greatly attracted to bouquets of 12 flat circle-shaped flowers (half white and half yellow). Furthermore, yellow flowers elicited landing more than other colors, regardless of the type of bouquet. With respect to the effect of mating on posterior foraging behavior, virgin individuals showed more movement than gravid ones. Our results shed light on the behavior of adult hoverflies and can be used to improve habitat management practices that seek to promote biological control.

We thank Ariadna Marmol and Quico Vila d’Abadal for their collaboration with data collection. Special thanks go to Francis Gilbert for his help differentiating between virgin and gravid females. This research was funded by Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (Spain), by means of the Project RTA 2013-00039-C03-00.