The plains-wanderer is considered to be one of Australia's rarest bird species.

After a successful breeding program, a group of 15 birds was able to be re-released to Oolambeyan National Park in the NSW Riverina.

The birds have been fitted with tiny satellite backpacks that will provide tracking data to researchers for the next two years.

"The birds have gone out with a satellite transmitter on the back of them," said Dave Parker, chairperson for NSW Department of Planning and Environment's Plains-wanderers National Recovery program.

"And between the bird, the satellites, and the computer at home, I'll be able to track where the birds are in the paddock while I'm sitting at home.

"This is the first release where we've trialed satellite telemetry. Each of the birds [has] been fitted with a backpack.

"And during the course of a day, there'll be a number of position fixes that the satellites pick up from the bird."

Previous attempts to map the birds' behaviour have been impacted by a low 12-week backpack battery life. The new transmitters will now be solar-powered to combat that problem.

"Plains-wanderers are a small, ground-dwelling bird that is particularly vulnerable to threats such as foxes and feral cats, and native grassland habitat loss," said NSW Environment Minister James Griffin.

"They're a critical part of the ecosystem because their presence or absence is an indicator of the health of their native habitat.

"These solar-backpack wearing plains-wanderers are paving the way for us to gather important data, which will ultimately help us improve our conservation efforts for wild populations into the future."

The 15 birds in the re-release program have been carefully selected for their genetic suitability.

Taronga Conservation Society in NSW supplied 11 birds, three from Monarto Safari Park in South Australia and one from Werribee Open Range Zoo in Victoria.

"So our main goal was to breed numbers in zoos as an insurance population," said Taronga Zoo keeper Mark O'Riordan.

But now we've got to a stage where we can actually release viable genetic populations out into the wild. So this is what we've done."

It follows the release of 16 birds in Victoria last year and another 10 birds in Hay, NSW in March 2022.

The plains-wanderer is the only representative of the pedionomidae family of birds. If it becomes extinct, the world will lose the last remaining members of the unique genus.