The world's largest cattle ranch has been forced to sell off its livestock and mothball operations because of the severe drought gripping much of Australia.

anna creek
©Chris McLennan
Drovers muster cattle at Anna Creek Station, South Australia

Anna Creek station, which is bigger than Israel, encompasses 9,267 square miles of scrub, sand dunes and savannah in the Outback of South Australia.

It is normally capable of supporting 16,000 cattle but the "Big Dry" - the worst drought in a century - has exhausted the land, forcing the herd to be whittled down to less than 2,000.

Half the cattle were sold for slaughter, while the rest were moved to other properties owned by S Kidman & Co, one of Australia's best known pastoral companies.

Over the next few months the number of cattle on the station is expected to dwindle even further, until only a handful will remain.

Anna Creek's normal staff of around 20 men and women has been reduced to a skeleton operation of half a dozen.

This is only the third time the ranch has been cleared of cattle since it was established more than a century ago.

"Since the European settlement of this part of Australia, we've only experienced these conditions twice before.

We've had four years of below average rainfall, and last year and the first six months of this year have been particularly savage," said Greg Campbell, managing director of Kidman, which was founded by cattle baron Sir Sidney Kidman in 1899.

"The drought is very severe. Before the weekend, when there were a few millimetres of rain, Anna Creek hadn't had rain since December."

The extreme lack of rain has killed off some of the Outback's hardiest tree species and is even threatening the survival of mulga and bluebush, tough shrubs which can withstand all but the worst dry spells.

The drought was part of a cyclical pattern rather than evidence of climate change, Mr Campbell said. "Although if this dry period continues, it might start to look more like climate change," he said.

Anna Creek is in one of the driest regions of the driest inhabited continent in the world.

Trying to raise thousands of high quality beef cattle, most of which are exported to Japan and the United States, might seem like madness.

But when the rains do arrive, the land springs to life, with the arid plains and sand hills carpeted in swaying grass and wild flowers.

"I've seen people standing thigh deep in clover," said Terry Omond, Kidman's human resources manager.

"It's the type of country that responds dramatically to rainfall. You only need a few inches, and you're laughing. It can get rain from the winter cold fronts coming up from the south, or from the tropical storms way up north. But it can miss out on both."

The station's managers must now simply sit tight and wait for a decent fall of rain - whenever that might be.

"It's a boom and bust environment," said Mr Omond. "It will come back to life eventually. No drought lasts forever."