Feral populations of horses often roam over extensive areas. When it becomes necessary to confine them for management purposes – for contraceptive treatment, for example – it becomes necessary to round them up.
Current methods of trapping are based on chasing the animals into a corralled area, often using helicopters.
Is there another way? A less stressful, less expensive, and safer alternative? Sue McDonnell and Catherine Torcivia, of the University of Pennsylvania School of Veterinary Medicine New Bolton Center, believe that there is.
They investigated whether it would be possible to get free-roaming horses to follow a drone into a corral. “This concept is based on the natural instinctive behavioural tendency of horses to become alert to intruders or novel objects and to respond as a herd according to the level of sympathetic arousal evoked,” they said.
They used a consumer-grade quadcopter drone to lead the university’s herd of 123 semi-feral ponies into corrals. Reporting their work in the journal Animals, they wrote: “The technique was successful on the first attempt as well as for seven of nine additional attempts over a period of 4 weeks, repeatedly to the same as well as to different destinations. The pace of following was primarily a fast walk, with an occasional slow trot. Family integrity was maintained.”
In all cases, one or more stallions were the first to alert to the approach of the drone as well as to initiate following of the drone’s retreat. “Those stallions vocalized in a characteristic loud distant call back to the remainder of the herd, which then reflexively coalesced and followed en masse.”
They found that to catch the horses’ interest, the drone was most effective when flying at 2-6 metres above the ground and within 10m ahead of the leading animals.
The authors conclude that their work shows preliminary proof of the concept of repeated capture of horses by leading with aircraft rather than chasing. They now plan to repeat the project on a herd of feral horses in a much larger enclosure than that in which these ponies were living.
“If successfully demonstrated in more extensive rangeland conditions, this method may eventually provide a lower-stress, more repeatable option of capturing feral horses, with implications for improved animal and human safety and welfare.”
Preliminary Proof of the Concept of Wild (Feral) Horses Following Light Aircraft into a Trap. McDonnell S, Torcivia C. Animals (Basel). (2020) Jan 2;10(1). pii: E80. https://doi.org/10.3390/ani10010080