Temporal resource partitioning and climatological influences on colony flight and foraging of stingless bees (Apidae; Meliponini) in Ugandan tropical forests

We studied the flight activity of two stingless bee species (Meliponula ferruginea and Meliponula nebulata) and the environmental factors influencing their flight. Two morphs of M. ferruginea were studied: M. ferruginea (brown) in Budongo forest and M. ferruginea (black) in Bwindi Park. The two bee species exited their nests in characteristically distinct foraging bouts suggesting that the recruitment methods used may be direct leading or ‘piloting’. The number of individuals in a returning bout was less than that in an exiting bout suggesting recruits do not follow experienced foragers the whole distance to food source, a phenomenon referred to as ‘partial piloting’. Flight period of M. ferruginea (black) and M. nebulata in Bwindi was restricted to a few hours each day. Meliponula nebulata foraged in the drizzle; a survival strategy, which could promote its reproductive fitness. Nectar and pollen foraging took place throughout the day while the removal of debris was greater in the late hours of the morning. Increased temperature resulted in significant increase in number of exiting bees. There was increase in number of exiting bees with decrease in humidity up to an optimal of 78% thereafter, increase in humidity resulted in reduced number of exiting bees.