Feral camels rounded up in Australian outback and ...

More than 120 camels that have been roaming outback Queensland and that, unusually for camels, “seem to have respect for fences” have been auctioned off online for about $250 a head.

The animals were rounded up in the spinifex desert country between the western Queensland town of Boulia, about 382km north of Birdsville, and the Northern Territory border.

They were bred on Alderley Station, where the Blackett family has been using the occasional handful for camel racing or selling through the Boulia camel races.

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It’s the first time the family has used an online auction to clear their herd, and attracted bids from as far away as Victoria.

Happily for the camels, who would have faced a 26-hour drive in an open-top truck had the Victorians been successful, they were snapped up by two local buyers.

The camels were sold in seven lots, with prices ranging from $300 a head for three groups of mothers with calves at foot, to $200 a head for cows without calves.

A lot of 32 bull camels sold for $240 a head.

Owner Scott Blackett told the ABC the cow and calf groups were sold to a buyer in Winton, western Queensland to be used for weed control.

They are reckoned to be particularly effective against prickly acacia, a thorny shrub imported to Australia from India that is ranked as one of the 20 worst weeds in Australia.

The rest were sold to a local “camel wheeler and dealer” with racing camels of his own, Blackett said.

The camels were mustered using helicopters and walked 60km to holding yards. According to the catalogue for the online auction, which was hosted on livestock auction platform Auction Plus, the camels appeared to be of “generally good” temperament and “seem to have respect for fences and go through gateways ok”.

Blackett told the ABC it was “the biggest muster we’ve done”.

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“We only ever used to go out and get a little handful for the local races in the camel tagging or if someone wanted a handful to train up for racing,” he said.

Camels were introduced to Australia in the 1840s as pack animals for British explorers. As of 2015 there were an estimated 1m feral camels in Australia, with the population at risk of doubling every nine years without culling.

They are effective against thorny weeds because they eat everything – according to the Northern Territory government, camels feed on more than 80% of the available plants in central Australia, causing significant damage to desert ecosystems and damaging fragile sand dunes. They have also been known to cause significant damage to manmade infrastructure in search of water, by pulling up pipes and destroying toilet blocks.

Last year South Australian officials approved the culling of up to 10,000 camels on Anangu Pitjantjatjara Yankunytjatjara (APY) lands because the drought had caused camels to converge on settlements in search of water.

The APY board member Marita Barker told the BBC at the time that the camels left the Aboriginal community “stuck in stinking hot and uncomfortable conditions, feeling unwell, because all the camels are coming in and knocking down fences, getting in around the houses and trying to get water through air-conditioners”.