Food Niche Overlap Among Neotropical Carpenter Bees (Hymenoptera: Apidae: Xylocopini) in an Agricultural System

Abstract

In the present study, we used niche overlap analysis and a network approach to investigate the use of floral resources by carpenter bees (Xylocopa spp.). We assessed the frequency of visit to different plant species and the activity time of carpenter bees in an agricultural system. Six species of carpenter bees were collected visiting flowers. Among the 48 interactions that were theoretically possible in the interaction network, only 19 were recorded (Connectance = 39.58%). The temporal overlap between pairs of species measured by the Shannon index (0 to 0.648) was lower than dietary overlap (0 to 0.967). The network analysis also showed that bees separated their niches more strongly in the temporal dimension (E = 0.72, P < 0.001) than in the dietary dimension (E = 0.55, P < 0.001). The levels of dietary and temporal overlap were strongly correlated with each other, as well as the time of highest frequency of visit coincided with the time of availability of resources by the most important plants (Moringa oleifera, Passiflora edulis, and Solanum palinacanthum). The correlation between dietary and temporal overlap is biologically explained by the presence of plants that structure the system by exerting a strong influence not only on the plant choice by foraging bees, but also on the time of resource collection.

Keywords

• carpenter bees
• plant network
• trophic niches
• temporal activity