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Satellite technology is being used to count African elephants from space.

Scientists believe it's a breakthrough that could help conservation of the animals.

The images are being taken from an Earth-observation satellite orbiting 600km (372 miles) above the planet's surface.

It could allow up to 5,000 sq km of elephant habitat - that's the area of around 700,000 football pitches - to be searched through on a single cloud-free day.

All the elephant counting is done via machine learning - a computer algorithm trained to identify elephants in a variety of backdrops.

"We just present examples to the algorithm and tell it, 'This is an elephant, this is not an elephant,'" said Dr Olga Isupova, from the University of Bath.

"By doing this, we can train the machine to recognise small details that we wouldn't be able to pick up with the naked eye."

The scientists looked first at South Africa's Addo Elephant National Park.

"It has a high density of elephants," said Dr Isla Duporge, a conservation scientist from the University of Oxford.

"And it has areas of thickets and of open savannah. So it's a great place to test our approach.

"While this is a proof of concept, it's ready to go. And conservation organisations are already interested in using this to replace surveys using aircraft."

Conservationists will have to pay for access to commercial satellites and the images they capture.

But the satellite images could offer a better alternative to counting done by humans in aircraft, which can be expensive, time-consuming and challenging when trying to cross international borders.

"In zoology, technology can move quite slowly. So being able to use the cutting-edge techniques for animal conservation is just really nice," " Dr Duporge said.