91av

Herding cattle using remote-controlled vehicles could be a welfare-friendly way to improve land management.

In a preliminary study, cows showed little fear as they walked away from the 16-centimetre-high cars rolling towards them, even the first time they saw the toys. The findings suggest farmers could use such simple, low-cost devices to prevent soil erosion, invasive plant growth and species loss caused by overgrazing, says at the University of Miyazaki in Japan.

Ultimately, the researchers hope to develop autonomous herding robots that don’t have to be driven by remote control.

“I believe robotic herding, such as with remote-controlled cars, has the potential to improve grazing distribution with minimised stress to the animals, including fear, discomfort and irritation,” he says.

Anzai and his colleague Hina Sakurai, also at the University of Miyazaki, rounded up 33 Japanese Black cows and their eight calves in a 1.1-hectare pasture at the university’s Sumiyoshi Livestock Science Station.

The scientists hid behind trees on seven separate days and targeted the adult animals with a red, remote-controlled Jeep Wrangler travelling at about 3.5 kilometres per hour. To make the toy more visible, they added a red flag set on a 110-centimetre pole.

The system was highly effective for field management, says Anzai, with grazing dropping tenfold in some of the most overgrazed areas of the pasture.

As for the cows, the animals responded to the car with very few signs of fear or aggression, he says. More than 90 per cent of the time they just walked away from the vehicle – and were usually followed by other members of their herd.

Removing the flag – which they had to do one very windy day – seemed to result in more fear reactions, says Anzai. That may have been because the car was small and quiet, and the flag prevented it from startling them by approaching unnoticed.

The method is less expensive and potentially more ethical than another technology being trialled on farms, “virtual fences” that give animals electric shocks through their collars when they approach the fence. This approach tends to result in lots of shocks for the “slow learners” in the herd, says Anzai. “It’s important to keep in mind that there will always be individual differences in behaviour and cognition,” he says.