Long-distance migration of hover flies (Diptera: Syrphidae): A global review

Understanding the seasonal ecology and behavior of hover flies (Diptera: Syrphidae) is a severely understudied, yet enormously significant area of research. The adult stages of most hover fly species are important pollinators for a variety of crop and non-crop plant species while many larvae are crucial biological control agents of soft-bodied pests like aphids. What is seldom acknowledged by ecologists and entomologists, is that many hover flies undergo astounding, annual, continental-scale migrations. A growing body of literature is beginning to reveal that this behavior can be found on most contents globally. Here, I will summarize our current knowledge of hover fly migration, including the evidence, mechanisms, and consequences of this behavior. I will also discuss critical areas of future research.