Impact of colony age on Trigona sp. activities in the green zones of Universitas Sumatera Utara Campus

Abstract

Trigona, a stingless bee pollinator, is widely domesticated for plant pollination due to its versatility and adaptability to various environments. This study aimed to assess the suitability of green open spaces in Universitas Sumatera Utara campus as a potential habitat for introducing Trigona sp. and to observe how colony age affects the foraging behavior of worker bees. Bee colonies were introduced into specific areas within the Faculty of Mathematics and Natural Sciences garden, positioned at a height of 3.4 meters above ground level. Nine bee hives were strategically placed around the garden for observations in October 2022, focusing on three different colonies based on their ages i.e. 2 m.o (Colony-A), 4 m.o (Colony-B), and 6 m.o (Colony-C). Activities were closely monitored between 8:00 AM and 4:00 PM, with at least three measurements taken for each 10-minute interval. The results showed variations in foraging activity among colonies in terms of peak hours and the number of worker bees. Colonies aged 4 and 6 months had over 50 foragers, while the 2-month-old colony had fewer. Notably, the 6-month-old colony displayed the highest average number of workers engaged in transporting pollen and resin, particularly at 9:00-10:00 AM. Results of Pearson’s correlation analysis indicated that light intensity negatively and significantly influenced the number of returning/entering worker bees, while wind velocity posed a negative and significant impact on the number of returning bees carrying resin. This study provides practical implications for the successful integration of Trigona bees into green open spaces, particularly inside campus area.