Unmanned aerial vehicles (UAV) have become unlikely prey for wedge-tailed eagles in Western Australia’s Goldfields, costing a mining giant more than $ 100,000 to replace its newest surveying tool.

Ten UAVs have been lost since South Africa’s Gold Fields, the world’s seventh-biggest gold producer, began operating the Trimble UX5 systems at its St Ives operations near Kambalda.

One crashed as a result of human error, while nine have been taken down by wedge-tailed eagles, which are known to have wingspans more than twice that of the 1-metre-wide UAVs.

The UAVs are constructed from foam and carbon fibre, and fly at an altitude of about 125 metres, reaching speeds of up to 92km/h.

Razor-sharp talons have turned the wedge-tailed eagles into what St Ives Mine surveyor Rick Steven calls “the natural enemy of the UAV”.

Mr Steven told 140 delegates at the Australasian Institute of Mining and Metallurgy’s Open Pit Operators’ Conference in Kalgoorlie-Boulder yesterday the introduction of UAVs was the biggest step forward for surveying since global positioning systems (GPS).

The UAVs capture large-scale photographs, down to 2cm resolution, and computer-generated, high-detail contouring of mined areas that are incorporated into future plans.

Mr Steven, who considers drones a “derogatory” term for the UAVs because pilots must pass a five-day course to fly them, showed delegates at the conference a recent photograph of an eagle attacking a UAV mid-air.

“People couldn’t believe I was able to get such a good photo of an eagle airborne, but I didn’t … another eagle took that photo,” he said.

“I was flying the tailings dam out at St Ives and I was getting attacked by two eagles simultaneously.

“I was trying to fly my UAV away from them and all of a sudden, at a high point, the eagle came down and sunk both its claws into the inside of the control box of the UX5.
“It turned the UX5 sideways and took a photo of the other eagle as it was coming in to attack.

“I think that’s the first recorded eagle selfie in history.”

The UAVs cost about $ 10,000 per body and another $ 10,000 per camera.

Mr Steven, who also holds a private pilot’s licence, said his team had attempted to engineer a solution to ward off eagle attacks by camouflaging the UAVs.

The original UX5 design was black, but St Ives has tried a rainbow-coloured pattern and even an eagle with wings, although Mr Steven said it “looked like an eagle but couldn’t fight back like an eagle”.

“That [wedge-tailed eagle] is my single biggest problem in the environment where I work for the UX5 … I am on my 12th [UAV],” he said.

“I am operating two at the moment. The one I am flying at the minute has just done its 78th flight.

“Nine out of the other 10 have been destroyed courtesy of this guy [eagle] — he’s its natural enemy. They’re big birds … the females are bigger and nastier.”