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Most flying animals rely primarily on visual cues to coordinate and control their trajectory when landing. Studies of visually guided landing typically involve animals that decrease their speed before touchdown. Here, we investigate the control strategy of the stingless beeScaptotrigona depilis, which instead accelerates when landing on its narrow hive entrance. By presenting artificial targets that resemble the entrance at different locations on the hive, we show that these accelerated landings are triggered by visual cues. We also found thatS. depilisinitiated landing and extended their legs when the angular size of the target reached a given threshold. Regardless of target size, the magnitude of acceleration was the same and the bees aimed for the same relative position on the target suggesting thatS. depilisuse a computationally simple but elegant ‘stereotyped' landing strategy that requires few visual cues.

To land, flying animals must simultaneously reduce speed and control their path to the target. While the control of approach speed has been studied in many different animals, little is known about the effect of target size on landing, particularly for small targets that require precise trajectory control. To begin to explore this, we recorded the stingless beesScaptotrigona depilislanding on their natural hive entrance—a narrow wax tube built by the bees themselves. Rather than decelerating before touchdown as most animals do,S. depilisaccelerates in preparation for its high precision landings on the narrow tube of wax. A simulation of traffic at the hive suggests that this counterintuitive landing strategy could confer a collective advantage to the colony by minimizing the risk of mid-air collisions and thus of traffic congestion. If the simulated size of the hive entrance increases and if traffic intensity decreases relative to the measured real-world values, ‘accelerated landing' ceases to provide a clear benefit, suggesting that it is only a useful strategy when target cross-section is small and landing traffic is high. We discuss this strategy in the context ofS. depilis' ecology and propose that it is an adaptive behaviour that benefits foraging and nest defence.