Alternative food source attractiveness to predatory augmentative biological control agents

Many factors influence the ability of natural enemies to regulate pest populations, including climatic conditions, competition, intraguild predation, and the availability of alternative food sources. Alternative food sources, such as supplemental prey, pollen, nectar, or honeydew, provide nutrients that can enhance the development, reproduction, and/or retention of natural enemies. In some contexts, such as in urban areas, alternative food sources may be less readily available which can drive natural enemy dispersal away from pest populations in search of plant derived food sources. Although supplementation with additional food sources has been performed in conservation biological control programs, integration of this tactic with augmentative biological control remains comparatively understudied. This research evaluates the chemotaxis of predatory insects to a variety of alternative food sources in the lab. We tested the behavioral responses of green lacewing larvae, Chryosperla rufilabris Burmeister, and scale destroyer beetle adults, Rhyzobius (=Lindorus) lophanthae (Blasidell), to a variety of food sources using a y-tube olfactometer. This study will provide useful information on supplements that might enhance the performance and/or retention of predators in urban settings and highlights avenues for future research into the improvement of augmentative biological control against urban plant pests.