(CNN) – Seven Tasmanian Devils They were born in the wild on mainland Australia, more than 3,000 years after they disappeared from the country.

The baby Tasmanian devils, known as hatchlings, were born in the 400-hectare Barrington Wildlife Sanctuary in New South Wales, Australian NGO Aussie Ark said in an Instagram post on Monday.

Tasmanian devils became extinct on the mainland after the arrival of the dingoes, a species of wild dog, and were confined to the island of Tasmania. However, its issue numbers took another hit from a contagious form of cancer known as Demon Facial Tumor Disease (DFTD), which has killed around 90% of the population since it was discovered in 1996.

Last September, the Aussie Ark put 11 of the creatures back into the wild on mainland Australia, following an earlier trial involving 15 of the marsupials, bringing the total of Tasmanian devils on the mainland to 26.

And now, just a few months after their release, the creatures have successfully reproduced, and conservationists have identified the tiny marsupials, which they say are the size of shelled peanuts, inside the mothers’ bags.

Tasmanian devils are the largest carnivorous marsupials in the world and are native predators.

Female Tasmanian devils give birth to between 20 and 40 young at a time, according to Tourism Australia. The pups run into the mother’s pouch, which only has four teats. Those who go public continue to live there for about three months.

“We have worked tirelessly for the better part of 10 years to return demons to the wilderness of mainland Australia in the hope that they will establish a sustainable population. Once they returned, it was all up to them, “Aussie Ark said in a statement Monday. “We had been watching them from afar until it was time to step in and confirm the birth of our first wild calves. And what a moment!

Tasmanian devils are the largest carnivorous marsupials in the world and are native predators. This means that their reintroduction will help control the populations of wild cats and foxes that hunt other endangered species. Demons are scavengers too, helping to keep their environment disease free.

11 Tasmanian devils were introduced into the wild on the Australian mainland last year.

In Tasmania itself, only 25,000 demons remain at large, according to Aussie Ark.

“Historically, though in their infancy, we’ve been able to bring demons back to the continent, and today is another milestone altogether,” said Tim Faulkner, president of Aussie Ark, in a video posted on Instagram.

– CNN’s Jack Guy contributed to this report.