I’ll be honest. I wasn’t expecting the camel.

The hours tick by slowly when you’re driving Australia’s Stuart Highway. Named after the 19th-Century explorer John McDouall Stuart, who was the first European to successfully traverse the continent from sea to sea and back again, the road broadly follows the route of his marathon journey. It’s 2,834km long; a near-endless spool of bitumen stretching from Port Augusta in the south to Darwin in the north, crossing what is largely open wilderness. They call it, with some understatement, ‘The Track’.

I knew to expect occasional wildlife, and sure enough the emptiness of the plains was sporadically broken up by the presence of the kind of climate-hardened animals Australia is famous for. There were kangaroos gazing blankly into the distance and wedge-tailed eagles hunkered over roadkill. On one occasion a dingo – a sandy-coloured wild dog – appeared out in the scrub, lean and wiry in the heat. I slept in the little outback towns that dot the route. Then, three days in, I saw a camel.

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I looked online that evening to make sure I hadn’t been hallucinating. Camels, you understand, are about as Australian as polar bears. Or rather, that used to be true. It turned out I’d just been ill-informed – and to a colossal degree. The outback was, and is, home to an extraordinary number of wild camels. The government-supported website Feral Scan, which monitors invasive species, puts the current number at between 1 and 1.2 million, with this amount reportedly doubling every eight or nine years. It’s a wonder, frankly, that the highway isn’t one continuous camel parade. So how on Earth did such a huge number of non-native animals come to be here?

The answer begins back in the pioneering days of characters like Stuart. To start with, there’s one crucial thing that needs to be understood about Australia’s outback. It’s big, in every direction. Very big. This is a mighty obvious statement, but it’s the absolute essence of what makes the outback the outback. The region covers more than 6 million sq km, or an area almost twice the size of India. Out here, the horizons are just precursors to more horizons.

When parts of coastal Australia were settled by the British from the late 1700s onwards, the colonial thinking of the day meant that a fuller exploration and understanding of this vast landmass became seen as a necessity. Indigenous people had lived here for tens of thousands of years – adapting, surviving, reading the land – but for newly arrived Europeans, the interior was a sun-scorched, unknowable expanse.

Inland expeditions began to take place with regularity, in often punishing conditions. Confusion sometimes reigned – a map from the early 1800s mistakenly shows a huge inland sea in the centre of the country – but, explorer by explorer, the continent was pieced together. Goldfields were discovered, outback settlements were founded and formative transport routes were established. But covering such extreme distances required packhorses or bullock teams, which generally lacked the staying power for long, thirsty days of travel. The alternative was obvious.

Between 1870 and 1920, as many as 20,000 camels were imported into Australia from the Arabian Peninsula, India and Afghanistan, together with at least 2,000 handlers, or cameleers, from the same regions. The animals were mainly dromedaries: half-ton ungulates with a single hump. They were ideally suited to the climate of the Australian interior: they could go weeks without water, and they had the stamina and strength to carry their loads and riders across what were often highly exposed, fiercely hot landscapes.

The impact made by these camels – and just as importantly, their handlers – over the following decades was considerable. In her co-authored book Australia’s Muslim Cameleers: Pioneers of the Inland, 1860s-1930s, Anna Kenny says that they have not been adequately acknowledged by mainstream Australia even though they made significant cultural and economic contributions to Australian society. “The cameleers opened lines of supply, transport and communication between isolated settlements, making the economic development of arid Australia possible. They also enriched the cultural landscape.”

The cameleers opened lines of supply... making the economic development of arid Australia possible

Laden camels became a fixture of outback life. They carried wool and water, telegraph poles and railway sleepers, tea and tobacco. Aboriginals began to incorporate camel hair into their artefacts. Even today, the luxury train that runs vertically across the country between Adelaide and Darwin is named The Ghan, in honour of the cameleers, who came to be referred to generically as ‘Afghans’.

By the 1930s, however, the camel industry went belly-up. The arrival of the internal combustion engine, and motorised transport, meant camels became almost redundant as pack-carriers. A four-legged mammal was no match for a goods vehicle, regardless of how stoic it remained in 40C heat. Thousands of camels were released into the wild, where, naturally, they thrived. Fast forward nine decades, and their numbers have ballooned.

But all is not well. Australia has had a serious camel problem for some time. The animals themselves may come across as gentle, lackadaisical beasts, but good luck telling that to the outback communities whose fences they routinely destroy, whose pipes they break and whose waterholes they drink dry. They also have a profound bearing on native wildlife, stripping their traditional grazing lands bare. In the words of modern-day explorer Simon Reeve, camels “are almost uniquely brilliant at surviving the conditions in the outback. Introducing them was short-term genius and long-term disaster.”

Introducing them was short-term genius and long-term disaster

Drastic measures have been employed to curb the population. It was reported in late 2013 that the government-funded Australian Feral Camel Management Project had culled around 160,000 camels in the years since 2009, usually by gunshot. Unsurprisingly, this blunt approach has been heavily criticised by some, and there have been attempts to turn the country’s influx of wild camels into a positive.

One such example is Summer Land Camels, which now grazes more than 550 camels on its 850-acre organic farm in Queensland. It vaunts the benefits of camel’s milk and camel’s milk products, which are high in essential unsaturated fatty acids and vitamin C, and has a range of dairy goods that includes everything from fromage blanc and marinated Persian feta to salted-caramel gelato – all made using camel’s milk. Elsewhere in Queensland, meanwhile, the QCamel dairy has announced it will be launching camel’s milk chocolates later this year.

Where the future lies for the country’s wild camels is uncertain. It still amazes me that there are quite so many of them out there. Since that first trip down the Stuart Highway I’ve made two more trans-continental journeys across Australia, but I haven’t yet spotted another wild camel. Not so much as a silhouette in the distance. But that’s the thing about Australia – it’s a place where the map stretches on forever, where horizons jelly in the heat, and where even the statistics exist on an unfathomable scale.

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