The release of 10 critically endangered turtles back into the only place they are found on Earth has helped to secure the species' future.

Key points: Ten critically endangered Bellinger River snapping turtles have been returned to their natural habitat in the Bellinger catchment, which is the only place they are found on Earth

Ten critically endangered Bellinger River snapping turtles have been returned to their natural habitat in the Bellinger catchment, which is the only place they are found on Earth Over 90 per cent of the turtle's population of approximately 4,500 was wiped out in 2015 due to a virus outbreak

Over 90 per cent of the turtle's population of approximately 4,500 was wiped out in 2015 due to a virus outbreak The program to help the Bellinger River Snapping Turtle is part of the NSW Government's $100 million Saving our Species Fund

New South Wales Environment Minister Matt Kean said it has provided a lifeline for the Bellinger River snapping turtle — one of the world's rarest turtle species, after a freak virus wiped out about 90 per cent of the population in three months.

"Before the disease outbreak, we estimate there were up to 4,500 of these freshwater turtles living in the Bellinger Catchment — the only place they're found on Earth," Mr Kean said.

"Sadly 90 per cent of the animals were wiped out in 2015 because of the virus.

"About 20 virus-free turtles were able to be collected from the river for a captive breeding program at Taronga Zoo in an effort to try to secure a future for this species and improve the environment for our future generations."

Bellinger River Snapping Turtle hatchlings. ( Supplied: Paul Fahy )

The program to help the Bellinger River Snapping Turtle is part of the NSW Government's $100 million Saving our Species Fund.

In the first year of the captive breeding program, 22 healthy turtles hatched, with another 31 healthy turtles hatching last year.

One of the turtles that was affected by the disease. ( Supplied: The Office of Environment and Heritage )

No cure for the virus, but 'this is hope'

Environmental group Ozgreen confirmed that the return of nine of the ten turtles had been successful — a figure that has boosted the community's confidence in the future for the species.

"This is hope for our pathway forward," Ozgreen co-founder Sue Lennox said.

Ozgreen manages Riverwatch, a program that has been monitoring the health of various rivers, including the Bellingen, on a monthly basis, for two years.

While a cure has not yet been found for the virus that initially wiped out most of the turtles, Ms Lennox said the next challenge is to rehabilitate the vegetation along the river's edge.

"That's the key to the success of restoring the river health and the return of the turtles," she said.

"Once we get that done I think we've secured the future of this river.

"Which is prob the healthiest river on the east coast as it is, but we need to keep it that way."

Conservationists say that the return of the turtles to their Bellinger river habitat gives them hope. ( Supplied: Paul Fahy )

The region's State MP, Melinda Pavey, said the local community has been helping with a citizen science project at the river.

She said the Bellingen Riverwatch volunteers have been regularly monitoring water quality to help the NSW Government with its work.

"This project in the Bellinger River shows that, with strong community support and partnerships, we can make real positive change to our threatened species," Ms Pavey said.

"The team will be closely monitoring the 10 turtles we've released back into the Bellinger River, with the hope of releasing many more in the future."