Diel and Lunar Flight Periodicities in the Light Brown Apple Moth, Epiphyas Postvittana (Walker) (Tortricidae) and Their Possible Adaptive Significance.

Abstract

Field observations on the flight activity of E. postvittana showed a die1 and a lunar periodicity of flight. There was a single daily flight peak at 21 h (Australian Eastern Standard Time); further analysis clearly showed two peaks, one large, 2-3 h after sunset, and one small, 3-4 h after sunrise. Males were active longer than females at both flight periods. Peak activity occurred shortly after new moon, around full moon, and shortly before new moon. As flight activity is controlled by light intensity, it is argued that the flight 2-3 h after sunrise and the peak in nocturnal flight activity at full moon are behavioural adaptations towards wind-assisted dispersal.