Microenvironmental Factors Regulating the Flight of Coptotermes formosanus Shiraki in Hawaii (Isoptera: Rhinotermitidae)

Wind velocity, light intensity, soil temperature, vapor pressure deficit in the colony, vapor pressure deficit at the surface of the flight slits, and vapor pressure deficit at 1 m above the soil were measured during the swarming season. The vapor pressure deficits and soil temperature were not critical factors for flight since they were in a favorable range during the observation period. Light intensity had to drop to 10.8 lumen/m2 before flight was initiated. Flight was terminated when the light was reduced to 0.14 lumen/m2. Light intensity, however, was not limiting since the intensity dropped every evening. The key microenvironmental factor regulating flight was the wind velocity at the flight slits. Flight was initiated if the wind velocity was below 3.7 km/h. If the wind increased to over 3.7 km/h after flight was started, flight was terminated