Psssshhhhhhh. You hear that? Probably not. But imagine you were just struck by a cool breeze billowing across the African savannah. While seemingly insignificant, the direction and magnitude of the wind can have a huge impact on the animals living in the area: especially on its local lions. Like many predators, African lions (Panthera leo) rely on their sense of smell, or olfaction, when hunting prey. The odors that lions smell can help them locate carcasses to scavenge, as well as large prey animals to ambush. However, the odors released by prey are highly impacted by the wind conditions. Researchers from the University of Oxford traveled to the Bubye Valley Conservancy in Zimbabwe to see how lions reacted to the wind conditions surrounding them.
For their study, Wijers et al. were interested in seeing if the lions displayed anemotaxis, which is adjusting position based on wind conditions. The researchers predicted that the lions would prefer to move crosswind, or perpendicular to the wind direction. This would allow them to maximize the amount of odors they could smell as they stalk the savannah. Being downwind from prey would also be beneficial, but the lions would be limited to smelling odors from prey directly in front of them, and not to the sides. The group also assumed that the lions would be inclined to travel farther in high wind conditions, to maximize the efficiency of their hunt. Faster moving winds would more quickly disseminate the odor particles of the prey animals, allowing them to reach the lion’s noses at a faster rate and from farther away. To test for their movement, the researchers attached GPS tracking collars to 29 different lions. Hunting behavior was differentiated from resting and local movement by tracking how far the lions traveled during a short interval. A weather data logger was used in tandem with the collars to record the daily wind conditions of the conservancy. Since lions are nocturnal predators, all data collection was taken during darkness hours to capture when they were on the hunt.
In the presence of high wind speeds, all lions were found to be more likely to move rather than remain stationary. Additionally the female lions, the hunters of the prides, were also found to travel farther as wind speeds increased. For the males, there was no substantial correlation between distance and wind speed. While not known for certain, this difference in behavior is assumed to occur due to behavioral sex differences. The males might have traveled farther in general to protect and manage their vast territories. While useful for acquiring scents, the increased movement in high wind speeds was also recognized as a potential strategy for reduced auditory noise, and allowing for a more stealthy ambush. When it came to the direction of the wind, the researchers found that the lions were 75% more likely to move crosswind, as opposed to parallel alongside the wind. This indicated anemotaxis, and a purposeful movement in response to the wind direction. While additional behaviors like avoiding rivals and inter-species conflict could have also impacted movement relative to the wind, there is no doubt that lions alter their movement direction when on the prowl.
The next time you are in the wind, make sure to be careful where you are standing!
References
Wijers, et al. 2022. Something in the wind: the influence of wind speed and direction on African lion movement behavior. Behavioral Ecology, p.1-8. https://academic.oup.com/beheco/advance-article/doi/10.1093/beheco/arac087/6701626
