Searching for the Right Target: Oviposition and Feeding Behavior in Bombylius Bee Flies (Diptera: Bombyliidae)

Roberto Boesi, Carlo Polidori, and Francesco Andrietti (2009) Searching for the right target: oviposition and feeding behavior in Bombylius bee flies (Diptera: Bombyliidae). Zoological Studies 48(2): 141-150. Bee flies (Diptera: Bombyliidae) are ectoparasitoids of larval stages of insects, often digger bees and wasps. We studied the behavior of 4 species of the genus Bombylius at a nest aggregation of their host bee, Lasioglossum malachurum Kirby, and at an adjacent feeding site. Although eggs were frequently thrown on vegetation patches, the number of eggs oviposited and the time spent in hovering flight were higher at host nest entrances. Bombylius females fed essentially on 3 (2 Caryophyllaceae and 1 Asteraceae) of 9 blooming plant species found in the area. Oviposition and feeding activities had different daily distributions. In general agreement with optimal foraging theories, Bombylius females exhibited the strongest interest in the predicted target, i.e., the host nest, and fed essentially on a few but highly exploited plants in the close vicinity of the host nesting site. http://zoolstud.sinica.edu.tw/Journals/48.2/141.pdf