Factors Influencing Flight Activity of Colonies of the Stingless Bee Trigona-Carbonaria (Hymenoptera, Apidae)

Abstract

Temporal patterns of flight activity and influence of climatic variables on activity of colonies of the potentially useful crop pollinator, Trigona carbonaria Smith, were investigated. Colonies of T. carbonaria were active all the year at the experimental site but the daily activity period was longer in the warmer months. Intensity of daily flight activity was greatest in September and least in May. Temperature and radiation were the most important variables affecting flight activity. They impose thresholds on activity, with flight occurring only at temperatures greater than 18-degrees-C and radiation greater than 15 W m-2. Temperature and radiation also influence the intensity of activity above the thresholds. Relative humidity, vapour pressure, cloud cover and wind speed had no significant effect. A variable measuring the hours from daily peak of activity was significantly correlated with flight activity, indicating an intrinsic diel pattern of activity. Daily variation in flight activity, representing the influence of unmeasured variables, was also significant.