The ostrich is native to Africa, where it lives in groups across the continent, but a very small number of them also call outback South Australia home.

It's estimated that very few of the large birds, which can grow to be almost three metres tall, still roam the red centre.

The birds were introduced into South Australia in the 1890s, and then again in the 1970s, when attempts were made to farm them for feathers and meat.

There have been ostrich sightings along the Birdsville Track between Marree and Mungeranie Station. ( ABC Rural )

However, most farms failed, and the flightless birds were released into the wild, where they have survived.

"One of the problems ostriches had in Australia was actually breeding well — they had a lot of infertility problems with the eggs," said SA Arid Lands' manager of scientific services Rob Brandle.

"Because they're quite a long-lived bird, they do survive in areas for a fair while and they're quite mobile as well."

Mr Brandle said the remaining ostriches that roam the outback are likely the same ostriches that were released from farms in the 1970s and 1980s.

He said the ostrich was able to survive in the Australian outback because the climate is similar to Africa's.

"Maybe we're a bit drier here overall, which is maybe why they don't do as well as something like emus," Mr Brandle said.

Australia's loneliest bird?

Mr Brandle said, because of their sporadic and limited population, ostriches were unlikely to survive in the long-term.

He said it would be a lonely life for an ostrich in the Australian outback.

"[There's] not a viable population, so I don't think they're going to breed up and go feral," he said.

"There could be occasional successful breeding of them — the adult birds lay a lot of eggs."

With the ostriches' low fertility rate and extremely small population, Mr Brandle said the birds were unlikely to see out the century in the outback.

'Easy to have around'

A video of an ostrich was recently recorded by a tourist 80 kilometres north of Marree along the unsealed Birdsville Track.

That video was likely filmed on Dulkaninna Station and its pastoral lease holder, David Bell, said he saw a very similar ostrich quite frequently.

"My son calls him Pete," Mr Bell said.

This ostrich was spotted wandering near the Birdsville Track, north of Marree. ( Supplied: Lisa Herbert )

"He rocked up six or seven years ago.

"Sometimes you might see him every couple of days and then you might not see him for a couple of months."

Mr Bell said, while there were never other ostriches with Pete, the bird got along well with other animals, including his cattle.

"He doesn't really cause any dramas at all, he does his own thing.

"You drive up to him and he runs away.

"He's fairly easy to have around."

Another pastoralist told the ABC there used to be an ostrich farm on his property.

He said up to 60 ostriches used to live there, but those numbers have since plummeted.

He said he still finds infertile ostrich eggs.

Business potential

South Australia's Minister for Primary Industries and Regional Development Tim Whetstone said ostrich farming could still be viable, despite its poor performance in the past.

"But if we're looking at ostriches running wild in pastoral country, I think we need to just gain an understanding of how many of the birds are roaming wild," he said.

Ostriches, like this one outside Oudtshoorn, east of Cape Town, are native to Africa. ( Alex Grimm: Reuters, file photo )

Goats and rabbits are among the most invasive introduced species that live in regional and remote South Australia and Mr Whetstone said they were a much bigger issue.

"With 50 or 60 ostriches roaming the outback, I think we need to have a watch and brief on just what their movement is, what the impact on the landscape is," he said.

"I would like to think that if they could be farmed or harvested, they could be turned into a business."

A prized find

BirdsSA President John Gitsham says ostriches are on many twitchers' bucket lists. ( Facebook )

Because of their scarcity, ostriches are a sought after species for 'twitchers' to tick off their bucket list.

A twitcher is a bird enthusiast who travels long distances to spot rare and exotic birds.

"The ostrich is certainly one that, even though it's not a native, it's on the Australian bird list," said BirdsSA president John Gitsham.

"There'd probably be a few birders wandering around the outback trying to find ostriches, so they can tick it off their list.

"If you happen to find one, enjoy it for what it is, appreciate that they're magnificent, [and] probably the largest bird species in the world."