Bee Body Size and Foraging Behavior Predict the Pollination Role of Bees in a Buzz-Pollinated Plant Community

Buzz pollination has been studied for over a century, yet the drivers shaping plant-pollinator interactions at the community level remain poorly understood. Although previous research has identified key functional traits associated with sonication-foraging behavior and taxonomic relationships among floral visitors, the specific bee traits that promote effective pollination are still unclear. In this study, we investigated which morphological and behavioral characteristics of flower-visiting bees predict pollination success within a plant community containing multiple buzz-pollinated species. Focusing on eight co-occurring, co-flowering plant species with poricidal anthers, we measured stigma contact (as a proxy for pollination efficiency), visitation rates, flower and whole plant handling time, intertegular span (body size), and pollen extraction mode across different bee species. Our results showed that both morphological and behavioral traits can predict pollination success. Specifically, stigma contact was positively associated with larger body size, suggesting that larger bees are more likely to touch the stigma during visits. In contrast, longer flower and plant handling times were linked to a low likelihood of stigma contacts-traits more commonly observed in smaller bees. Bees that used floral sonication visited more flowers and plants per unit time and contacted stigmas approximately four times more frequently than non-sonicating bees. However, detailed aspects of sonication behavior-such as the number and duration of buzzes-were not associated with pollination efficiency. These findings suggest that while bees visiting buzz-pollinated flowers may share similar pollen extraction mechanisms, variation in physical and behavioral traits plays a crucial role in shaping pollination dynamics.