American farmers are using the voice of Scarlett Johansson and rock music to scare wolves away from their cattle.

Quadcopter drones blaring AC/DC and violent film scenes are being used by the US Department of Agriculture (USDA) to scare off wolves that have been preying on cattle in Oregon and California.

The drones are equipped with thermal cameras that can spot wolves lurking in the darkness and shine a light on them.

They also have a loudspeaker that broadcasts alarming noises including the sounds of fireworks, gunshots and people arguing. One recording is of the fight scene between Johansson and Adam Driver in the film Marriage Story.

“I need the wolves to respond and know that, hey, humans are bad,” Paul Wolf, a USDA district supervisor in Oregon, told The Wall Street Journal.

Wolf population has soared in US

Mr Wolf has led a government study since 2022 on using drones to frighten away the animals.

It is the latest technological innovation in the fight to stop attacks by wolves in America’s rural north west.

The US wolf population has soared since they were reintroduced to Yellowstone National Park, Wyoming, in 1995, growing from 300 to around 6,000, excluding Alaska.

As a result, attacks on cattle and sheep have shot up, with farmers often unable to harm the predators because of their protected status.

Jim and Mary Rickert, who own Prather Ranch in California, have lost as many as 40 calves to wolf attacks over the past year.

“It’s basically like driving through Burger King, easy pickings for them,” Mrs Rickert, 73, told the WSJ.

Since their deployment, drones have dramatically reduced the number of wolf attacks in Oregon.

All-night stakeouts stop attacks

In the Klamath Basin, in the southern part of the state, the number of cows killed by wolves fell from 11 over a 20-day period to two over the next 85 days following the drones’ introduction.

The $20,000 flying vehicles are capable of doing a battery “hot swap”, meaning their power source can be changed without switching the drone off, enabling near continuous surveillance.

Mr Wolf and his team travel to ranches in Oregon and California where there have been reports of calves killed by wolves and carry out all-night stakeouts to ward off further attacks.

Footage of the team at work shows a screen displaying a wolf illuminated by a spotlight, captured by a night-vision camera on a drone hovering above.

“Hey get out of here! Get!” Mr Wolf’s colleague, Colby McAdams, shouted via the microphone on the drone’s controller, causing the animal to run off.