Foraging Activity and Preference of Pollen Sources by Stingless Bee, Heterotrigona itama in Tropical Lowland Forest of Terengganu

Abstract

Stingless bees (Hymenoptera: Apidae: Meliponini) are a highly diversified group of eusocial corbiculate bees distributed in tropical and subtropical areas. However, studies on the relation of stingless bee activeness with environmental parameters and pollen source preference are very limited particularly from the lowland forest of East Coast Peninsular Malaysia. Hence, this study aimed to determine the relationship between stingless bee, Heterotrigona itama foraging activity with environmental factors (temperature, humidity, and light intensity) and preference of floral sources in a meliponiary of Marang, Terengganu. The foraging activities of five healthy colonies of H. itama were observed from 0700 to 1700 hours on hot sunny days for eight months of study period (August 2020 – September 2021). The foraging activity was enumerated using camera recording for 10 minutes at one-hour intervals (0700-1700 hours). In this study, the peak time for H. itama to go forage was observed at 0900 until 1100 hours in the early morning and declined rapidly from 1100 until 1700 hours. October 2020 recorded the highest activeness of stingless bees, followed by August 2021 and September 2021. There was a significant difference in the interaction of stingless bee activeness between time and months [F67,424 = 3.498, p<0.05]. However, temperature, humidity and light intensity did not significantly influence the activeness of stingless bees. Acacia mangium was the most frequent pollen grain collected by H. itama, followed by Melastoma malabathricum and other pollen types were considered minor pollen types (<15%). Findings from this study can help beekeepers to understand the foraging behaviour of stingless bee colonies and the preference of the available pollen resources for sustainable meliponiculture management practice.