Automatic tracking method for multiple honeybees using backward-play movies

In recent studies, researchers can easily record the behaviors of animals by digital video cameras, which provide high functionality at reasonable cost. However, it is a laborious and time-consuming manual task for them to extract the useful behavioral data from these videos. We recently proposed a tracking method for unmarked multiple honeybees in a flat arena, named the “K-Track” algorithm. The algorithm can successfully identify and track nearly 90% of interaction cases of targets. In this study, we proposed an improved method for the existing K-Track algorithm by tracking results using backward-play movie. If the tracking results differed between the forward and backward episodes, one of them had probably resulted from correct tracking. Therefore, by comparing the forward and backward trajectories of the same interaction, we assumed that there is the potential for an increase in tracking accuracy. In the experiments, K-Track using backward movies successfully tracked four out of five situations that was failed by original K-Track and we confirmed that the method has the potential of improved tracking accuracy.