Foraging dynamics and floral fidelity of stingless bees Tetragonula cf. biroi in a controlled tropical floral array

Understanding the foraging behavior of stingless bees is essential for optimizing their role as pollinators in tropical agroecosystems. In this study, the foraging dynamics and floral fidelity of Tetragonula cf. biroi were investigated using a controlled floral array of six tropical plant species: Cosmos sulphureus, Tagetes erecta, Catharanthus roseus, Clitoria ternatea, Helianthus annuus var. dwarf, and Hibiscus sabdariffa. Observations were conducted over 15 days under consistent environmental conditions. Foraging activity showed a clear diurnal peak between 09:00 and 11:00 and was positively associated with ambient light and negatively affected by temperatures exceeding 32 °C. Floral constancy—defined here as the proportion of same-species visits within a foraging bout—was moderate to high overall. Across the six species tested, open, brightly coloured composites (e.g., Cosmos sulphureus and Tagetes erecta) received the highest visitation, consistent with higher nectar volumes and accessible morphologies, whereas tubular or low-nectar flowers elicited more switching. These findings highlight the selectivity and behavioral plasticity of T. cf. biroi in response to floral and environmental cues. Incorporating high-reward, visually attractive plant species into agroecosystems can enhance stingless bee foraging stability and support pollination services. This study provides valuable insights into stingless bee ecology and offers practical guidance for designing pollinator-friendly landscapes for tropical agricultural systems.