In order to evaluate the migratory potential of the brown planthopper, Nilaparvata lugens, under as near to normal environmental conditions as possible, adult macropterous insects were captured from the field whilst in the process of flight initiation at the times of their natural take-off peaks. The insects were then flight-mounted and flown in the field. Average flight durations following the dusk take-off were 4 hr 55 min for males and 6 hr 17 min for females. However, many insects flew throughout the night and there was a high frequency of flight cessation at dawn. Following a dawn take-off both sexes flew for much shorter periods, an average of 2 hr 00 min for males and 2 hr 04 min for females. Female insects were reluctant to initiate a second major flight. The role of mating and ovary development in female flight willingness is discussed.
