Drone technology has shown its potential to monitor horses in a study, but the researchers stress that the animals involved were used to humans and machinery.
How wild horses, or domestic horses less used to machinery, might react to the technology has yet to be determined.
Tomoko Saitoh and Moyu Kobayashi, with the Obihiro University of Agriculture and Veterinary Medicine in Japan, noted that advances in drone technology have led to their increased use in animal research.
The researchers set out to learn about the potential for drone use in livestock management, using the technology to observe horse behavior and verify the appropriate horse–drone distance for aerial behavioral observations.
Recordings were made over two months on 11 horses kept at the university using a Phantom 4 Pro drone. Four flight altitudes were tested — 60m, 50m, 40, and 30m — to investigate the reactions of the horses to the drones and observe their behavior.
In each case, the drone was flown into a position hovering over a selected horse at 60m, where it recorded five minutes of video footage. It would then lower 10m and record another five minutes. This process was repeated for the 40m and 30m altitude observations.
Saitoh and Kobayashi reported that none of the horses displayed avoidance behavior at any flight altitude, and the observer was able to distinguish between any two horses.
Recorded behaviors included foraging, moving, standing, recumbency, avoidance, and others.
Foraging was the most common behavior observed, both directly and in the drone videos, being observed for 75 to 95% of the total observation time.
“These results indicate that horse behavior can be discerned with equal accuracy by both direct and recorded drone video observations,” they said. “Drones can be useful for recording and analyzing horse behavior,” they concluded.
The pair noted that drones have already been deployed in wildlife research in relation to dugongs, elephants, red-crowned cranes, penguins, Antarctic shags, and Southern elephant seals.
“They can be used for behavioral surveys of animals inhabiting difficult-to-access areas and/or highly sensitive and aggressive animals,” they said.
“In considering using drones in horse behavioral surveys, it is necessary to clarify the effects of drone usage on the natural behavior of horses.”
The authors noted a study that assessed the impact of drones on free-roaming bears. They exhibited a stress response to unmanned aerial vehicle flights, as evidenced by their elevated heart rates, but they rarely showed a behavioral response.
“Our experiment recorded only behavioral data,” the paid said. “Therefore, there is a possibility that there was a potential stress response that did not appear in their behavior.”
Even at 30m, the drone did not affect the horses’ behavior in the study, as long as it was stationary. “However, the drone may not have affected the horses’ behavior because they were accustomed to the existence of humans and the operation of equipment.
“Furthermore, since the drone remained stationary in the air in this experiment, it will be necessary for future studies to investigate how horses react to drone flights when they follow horses in a rapid motion with accompanying motor noise.”
They continued: “Further study is needed to clarify behaviors that are not targeted in this study, and experiments that seek a more direct way to the practical application of drones to horse management are required.”
Saitoh, T.; Kobayashi, M. Appropriate Drone Flight Altitude for Horse Behavioral Observation. Drones 2021, 5, 71. https://doi.org/10.3390/drones5030071
Horsetalk editor’s note: This experiment was conducted under carefully controlled conditions. There have been news reports of horses being spooked by drones flown near them in their paddock environment, in some cases suffering injury.