Pollen utilization of syrphid flies in Pennsylvania apple orchard agroecosystem

Understanding pollen utilization of beneficial insects in agroecosystems provides valuable information about resources needed to promote and support the population. Adult syrphid flies, similar to native and wild bees, utilize pollen and nectar from the agricultural landscape, additionally, the predaceous larval stage serve as natural enemies of several agricultural pests (hemipterans). Using pinned syrphid fly specimens collected over 3 years by pan-trapping methods in six commercial apple orchards, we are able to identify the gut pollen content by comparing it to floral resources available in the agroecosystem. Orchards participated in conventional broad-spectrum vs reduced-risk pesticide application study. Approximately 9000 individual specimens from 20 species of syrphid flies have been identified.