Meeting Abstract
The origins and ecological consequences of division of labor in insect colonies are of great importance to understanding the evolution of social insects. Direct observation of individual behavioral patterns within the hive and their connections to ecologically relevant traits outside the hive (i.e. foraging capacity and flight performance) presents difficulties in insects, however, because of their size and the labor-intensive nature of manually tracking individuals. In this study, we explore the connections between in-hive behavior, temporal foraging pattern, and flight performance in bumblebees (Bombus impatiens) using beeTracker, a new, freely available tracking program. Inspired by similar programs that use optical tags to identify individuals (such as ARTag), this program tracks the position of unique tags from video frames or still images. Here, we use this program to track dozens to hundreds of individual bumblebees per colony, both within the hive and as they enter and exit the hive to forage in the natural environment. In combination with an automated motion capture system adjacent to the hive, this system also allows us to quantify individual-level maneuvering flight performance over the course of several weeks. Finally, an automated scale system provides data on individual masses of bees as they exit and enter the hive, allowing quantification of individual resource intake rates. Our results provide support for strong and stable inter-individual differences in both foraging behavior and brood-care in the hive. Interestingly, behavioral performance in these tasks appears largely unrelated to body size, which has been hypothesized to drive behavioral specialization in bumblebees.
