Cattle won’t forget a scary drone

You can observe cattle with drones, and you can handle them with drones, "but you're probably going to have a bad time trying to do both," she says.

"Let's say I wanted to look at cattle with drones and I also wanted to chase cattle with drones. I would need different drones with different sounds. So they might learn that one brand of drone is ok but the other brand with a different sound is bad.

"I would want to get them used to being observed with drones first before I'd start chasing them with drones. If you just get in there and start chasing first, they are going to be afraid of all drones. You aren't going to be able to observe them; they will run away from them."

Grandin says she has seen a video of a drone flown high above cattle, then moved over and slowly lowered down. The cattle just looked up at it.

"Make sure at the beginning that your cattle don't have a scary experience with a drone because then they will be scared of all drones. The initial experience should be just observing them with it; then if I wanted to chase them I'd never use the 'good' drone I initially trained them with."

A chase drone needs to look very different from the observing drone. "I'd get another one that was the 'bad' one and I might tie a flag or ribbons or something to the back of it to make it look even more different."