Last year, a grand plan to reintroduce platypuses into Sydney’s Royal National Park began with the release of six females followed, a week later, by four males.

It was a long and complex project – identifying and relocating the small native animals from their homes in the Snowy Mountains.

Royal National is one of the oldest national parks in the world, established in 1879 by the colonial government of New South Wales.

Platypuses were a common sight back then and continued to be spotted occasionally in the park’s rivers until the beginning of the 1970s.

But in the past 50 years, confirmed sightings dwindled to nothing, and researchers concluded the species was extinct within the park.

After being captured in the Snowy Mountains, the 10 platypuses spent some time at Taronga Park Zoo, transitioning to their new circumstances and feted as celebrities.

On a cool, mid-autumnal afternoon, just an hour or so before dusk, the big moment arrived to release the first of the platypuses into Royal National Park from the banks of the Hacking River.

VIPs, government ministers and scientists mingled and the platypuses received their own welcome (back) to country from Indigenous leader and Park Ranger, Uncle Dean Kelly, who told the Dreamtime story about how Djumalung, or the platypus, came to be.

First to be released were the six females, named Delphi, Pandora, Kombucha, Kryptonite, Daiki, and Gerzgerzitsky.

The following week it was the males’ turn. The handlers had to take extra care letting them out of the bags due to their venomous spurs – which by all accounts can cause an injury that is incredibly painful and takes months to heal.

The males were Draco, Norris, Prometheus, and a particularly mischievous platypus called Chaos. Instead of heading for the river, Chaos darted left and ran straight under the legs of onlookers.

All 10 platypuses were tagged with small tracking devices that allows the scientists and National Park rangers to monitor their activity and movements.

All that happened six months ago.

It’s early days yet, but researchers say the platypuses appear to be thriving in their new habitat.

The latest data show nine of the 10 reintroduced platypuses are within the tracked area of the Hastings River.

The 10th platypus has ventured beyond the team’s tracking capabilities, but the researchers believe it is exploring one of the smaller creeks in the habitat.

Attention has now shifted to the continuous improvement of the park’s water quality and that of the catchment area that feeds into the park.

Platypus researcher, Dr Tahneal Hawke, said the water quality was generally good, offering suitable resources for the platypuses.

“As they enter their breeding season, we are optimistic they will breed,” she said.