Face Fly Dispersal, Nocturnal Resting Places, and Activity During Sunset as Observed in 196312

Abstract

In preliminary studies, activity of face flies, Musca autumnalis DeGeer, during sunset was observed by releasing marked flies near 2 cows about 1 hr before sunset. A few marked flies and a few wild ones were noted on the cows several minutes after release. They appeared to leave the cattle when the level of natural light was still so high that artificial light would probably not be an effective attractant. In dispersal studies 24,000 individually marked flies were released in 4 different areas, 6000 flies per area. Several marked flies were found 2 miles from their release point after 24 hr. One fly was found 4 miles away after 5 days. Attempts were made to determine the flies' nocturnal resting places by releasing marked flies before sunset and then searching for them after sunset with UV lamps. Searches for marked flies during the late fall indicated that they spend the night in trees and in tall weeds rather than in or around barns.