Outline of a bull camel in the Simpson Desert at dusk.

After motor vehicles became available camels were often released and their descendants are now a feral population of 600,000 or more throughout Australia. They were imported to South Australia in the 1860s and bred at Sir Thomas Elder's Beltana stud farm. Used extensively in the exploration of central Australia and for the building of telegraph and railway lines and by hawkers who carried goods to remote stations, large numbers of the animals were released into the wild rather than killing them once they were no longer needed for transport purposes.

However in 2007 it was reported that camels are once more being used for exporation in South Australia:
A team of geologists from the State Government and uranium miner Heathgate Resources has been on a camel trek near Arkaroola in the northern Flinders Ranges to test for uranium. Heathgate's chief geologist Jess Oram says there was no other practical way to get into the area. "The area is incredibly rugged and with no tracks in" she said. "It's even too rugged for helicopters because of the terrain, it's quite hilly, and also the vegetation - it's pretty difficult to get a chopper down in there, so the best way in was to use camels."
ABC News Online Thursday, May 17, 2007. 9:04am (AEST)