A method for bee activities recognition from videos captured at the beehive entrance

Honeybees play an important role in the ecosystem and agricultural economy. To maintain and develop healthy bee colonies, monitoring and recognizing bee activities at the beehive entrance is necessary. In this research, we extend the method in [6] to track and recognize the flight-in and flight-out activities of both pollen-bearing and non-pollen-bearing bees in videos recorded at the beehive entrance. To achieve this goal, a framework consisting of bee detection, bee tracking, and bee activity recognition is proposed. In the first step, to address the imbalance between the number of pollen-bearing and non-pollen-bearing bees, we employed a detection method combining YOLOv5 and the focal loss function. Subsequently, in the tracking step, based on the detection results of the first step, two OC-SORT-based trackers were initialized to determine the trajectories of pollen-bearing and non-pollen-bearing bees. Finally, in the activity recognition step, rules are applied to the tracked trajectories to determine the instantaneous activity states of honey bees and to recognize their overall activities. The experimental results show that the detection step obtained an overall precision of 0.972 whereas the tracking step achieved HOTA values ​​of 77.28%, MOTA of 90.09%, and MOTP of 84.98%.