Dispersal flights of termites are the result of the sum of a number of complex and highly orchestrated behavioural responses by different castes to a variety of cues. Macrotermes natalensis (Haviland) produced a single brood of alates each year. These alates left their parent nests in dispersal flights early in the summer rainy season from late September to early December, with a peak during October. Rainfall was the primary stimulatory factor triggering flight; 5 mm was the threshold for initial flights. Large flights usually occurred later in the season and required more rain to trigger them. The initiation and duration of individual flights were regulated by factors such as temperature, light intensity, and wind. The threshold temperature for swarming flights lay between 17–19°C. If the air temperature dropped below this the flight was aborted. The species did not fly during rain and major flights took place between 39 % and 90 % relative humidity. Windless conditions were favoured for flight which ensured that alates were not distributed so widely that the chances of finding a mate were jeopardized and that the female sex pheromone was not so dispersed that males failed to locate mates. Flight times varied over the flight season as they were governed by light intensity and took place at dusk in low light intensities with alates leaving the nest from 1 to 30 lux. The majority of swarming flights occurred with a waxing moon.