Flight range and resource loading-unloading behavior of stingless bee Tetragonula iridipennis (Smith)

Abstract

Stingless bees are generalist visitors, forage with a high degree of floral fidelity, and thereby play an important role as pollinators. Management of stingless bees is considered to be an enhancer of crop yield and as well as an eco-friendly strategy to conserve biodiversity. While Tetragonula iridipennis Smith is one of the most common species of stingless bees, its foraging behavior is not very well understood. Therefore, we conducted this study to estimate the maximum foraging distance, foraging trips (number and duration), resource carrying capacity and resource loading-unloading time of the dammar bee (T. iridipennis) in West Bengal, India. Flight range was estimated by feeder training and capture-recapture techniques. The maximum foraging distance of 319.86 ± 53.01 m was recorded with an artificial feeding technique, whereas 840.21 ± 105.94 m was recorded as the maximum homing distance in capture-recapture technique. Flight distance significantly differed according to seasons as well as from colony to colony. Number of foraging trips performed daily by a forager significantly depended on the distance of resources, attributes of resources (type, quality, availability and accessibility), seasons and weather conditions. Resource loading time as well as duration of foraging trips varied according to day time and depended on resource availability and accessibility. Resource unloading times for nectar and pollen loads were much lower than the resin or latex loads. Plant resources collecting bees allocated their tasks into several groups, and this task allocation showed flexibility to some extent depending on the demand of the colony and surrounding resource availability.