A second batch of western quolls will be released in South Australia's Flinders Ranges National Park after a successful trial reintroduction.

Forty-one of the native marsupials were released around Wilpena Pound last April, in the first phase of an ambitious five-year plan to bring the vulnerable species back to the region after an absence of more than a century.

Until the relocation program, western quolls were only found in the wild in the south-west corner of Western Australia, where numbers have risen under a state government-run recovery program.

The Foundation for Australia's Most Endangered Species is raising the $1.7 million needed to fund the reintroduction project in South Australia.

Cheryl Hill from the foundation said the trial had gone better than expected.

"Even though we based the work on really good planning and really good expertise from the folks in Western Australia, we could have lost the lot," Ms Hill said.

"As it turns out we learnt more than we thought we would, we've done better than we thought we would and this is terribly exciting because it may be the future for wildlife ... bringing back something is pretty rare."

As expected feral cats have been the biggest problem, killing around a third of the original quolls that were released.

Environment Department spokesman Robert Brandle said while a long-term baiting program funded by the State Government had kept foxes away from the marsupials, cats were trickier to control because they preferred live prey.

"Cats are absolutely everywhere through the environment and that's a problem with managing them at a local level like we are here," Mr Brandle said.

"You pull them out and very quickly they come back in from the sides."

Up to 60 babies born since project's beginning

Despite the losses, project co-ordinator and reintroduction specialist Katherine Moseby said all but one of the surviving females had reproduced.

It is estimated up to 60 baby quolls have been born since they were reintroduced in South Australia. ( Supplied: Katherine Moseby )

"Pretty well they were breeding at full capacity, which is quite exciting for the first year of a release," she said.

"What it does tell you is that there's plenty of food around and they've adapted well to the local conditions."

It is estimated about 60 quolls were born.

One of the quolls later killed by a feral cat had given birth to seven babies, which were brought back to Adelaide Zoo where they were hand reared.

The seven orphans have now been returned to the national park.

Ms Moseby and her team are now trying to work out how many of the juveniles are still alive after being weaned and left to fend for themselves in the wild.

So far they are very encouraged by how many they are catching in traps.

Another round of trapping in March will provide a clearer picture of the population, but the results have already been good enough to approve the release of a second lot of quolls later this year.

The newcomers will be brought in just before mating season and by then it is expected the juveniles will also be ready to do their bit to swell the ranks.

"They actually have their highest fecundity in their first year so we're hoping that as soon as they're big enough they'll be straight into it," Ms Moseby said.

"So as long as they can keep evading these cats we can double, triple our population very quickly."

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