Wind drives temporal variation in pollinator visitation in a fragmented tropical forest

Abstract

Wind is a critical factor in the ecology of pollinating insects such as bees. However, the role of wind in determining patterns of bee abundance and floral visitation rates across space and time is not well understood. Orchid bees are an important and diverse group of neotropical pollinators that harvest pollen, nectar and resin from plants. In addition, male orchid bees collect volatile scents that they store in special chambers in their hind legs, and for which the wind-based dispersal of odors may play a particularly crucial role. Here we take advantage of this specialized scent foraging behavior to study the effects of wind on orchid bee visitation at scent sources in a fragmented tropical forest ecosystem. We find that temporal changes in wind speed and turbulence are correlated with visitation to scent stations within sites, while local landscape structure is a strong determinant of spatial variation in visitation across nearby sites. These results suggest that the increased dispersal of attractive scents provided by wind and turbulence outweighs any biomechanical or energetic costs that might deter bees from foraging in these conditions. Overall, our results highlight the significance of wind in the ecology of these important pollinators in neotropical forests.