Reuters Two feral camels stand by The Olgas rock formations around 240 miles southwest of Alice Springs.

First imported to Australia in the 1800s from India, Arabia and Afghanistan as a cheap and hardy means of transport, the number of humpback camels Down Under has since exploded to more than a million and become a major headache for local landowners as well as a growing concern for ecologists. With few natural predators, the population of feral camels has skyrocketed across the states of Western Australia, South Australia and Queensland, making it the largest herd on earth.

“One of the biggest problems is that they drink large amounts of water,” explorer and writer Simon Reeve told the BBC. “They gulp down gallons at a time and cause millions of pounds worth of damage to farms and water holes which are used to water stock. They also drink dry water holes belonging to the Aborigines.” Camels are also responsible for damaging vital infrastructure such as fences, water tanks, pumps and pipes. Ecologists fear the camels’ vast appetites will ravage traditional food sources for native species such as kangaroos, emus and assorted reptiles.

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Authorities are now trying to come up with a solution to the predicament. Farmers and ranchers have taken to shooting the animals and leaving them to die in the open, while other schemes involve herding camels into pens with helicopters and selling them off for meat, a controversial but nonetheless common practice with other animals bred specifically for export. As the Sydney Morning Herald reported earlier this month, “Today, millions of animals, mostly sheep and beef cattle but also dairy cows, buffalo, camels, deer and goats, are loaded onto ships and planes in Australia each year,” en route to slaughterhouses abroad. Dubbed “ships of death” by animal-rights groups, the horrific conditions on the journeys have been likened to those on slave-trade ships.

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Concern for the camels — mainly single-humped Dromedaries with a few double-humped Bactrians in the mix — have become so widespread that the animals’ plight is the subject of a new documentary called Camels in the Outback, which follows a Qatari camel herder on his trip to Australia in an effort to help end the slaughter. The 48-minute film, which was directed by Yasir Khan, can be viewed in its entirety on YouTube.

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