The discovery of a human skull on a crumbling riverbank in Western Australia has led to one of the largest recoveries of human remains from unmarked grave sites in Australia.

Now scientists are using the latest DNA technology to try to return more than 70 sets of these long-lost bones to their living relatives.

WARNING: This story may contain images of the remains of deceased Aboriginal people.

Last year, children playing on the banks of the Kimberley's Fitzroy River thought they had found an old football in the eroded bank — but had instead uncovered a human remnant from one of the town's earliest inhabitants.

Bunuba Elder Mary Aiken grew up by the river which snakes through the town of Fitzroy Crossing.

She said the community began to panic when they realised that years of flooding and erosion had started to sweep the bones away from the old Pioneer Cemetery.

"There was a sense of urgency," she said.

"No-one ever thought that some of those remains would be exposed to elements and flood waters each year."

Several of her relatives were buried there in unmarked plots.

"I didn't see any sense in leaving these people, our people down there," Mrs Aiken said.

"I've got several members of the family down there too and several members of the family washed away, the whole lot."

The Fitzroy Crossing community gather to put the remains of their relatives to rest. ( Matt Bamford )

Culture centre steps in

The Kimberley Aboriginal Law and Culture Centre (KALACC) stepped in to try to save as many remains as possible before the floods arrived.

KALACC Repatriation Officer Neil Carter has been coordinating the project over the past 18 months under the supervision of elders.

The eclectic team also features archaeologists collaborating with Gooniyandi and Bunuba Rangers from the Fitzroy Valley.

"The general belief is that if people are not put back into country then their spirits cannot rest," he said.

"When you die you should be placed back in your own country so that are reconnected with Mother Earth.

Neil Carter from the Kimberley Aboriginal Law and Culture Centre inspects the site where dozens of remains were found by the Fitzroy River ( ABC Kimberley: Matt Bamford )

"Aboriginal people believe that you come from the land and you should be placed back to the land where you were born, where you came from."

He said that so far 78 sets of remains have been recovered.

"They were buried mostly in body bags, some with some were buried in cloth, canvas, in sheets or blankets and there were no remains buried in coffins, they were just all in body bags," he said.

While this is regarded as a significant achievement, it is thought that between 10 and 20 sets of bones have been lost.

"It awakened a lot of emotions," Mr Carter said.

"How people were buried here without really consulting their family, people didn't have a choice, they were just buried here.

"All those things came back and the awakening of emotions about their uncle or their grandfather, their aunty, their sister, and at that time they didn't have the opportunity to take their family back to country."

DNA to link remains with relatives

Researchers specialising in genetics are now trying to link these bones to their living relatives.

DNA expert Bastien Llamas from the University of Adelaide has been working on the project as a consultant for the National Centre for Indigenous Genomics.

He has been taking samples from the remains and living residents, including some of the rangers, to try to connect families with their missing relatives.

Scientists are taking samples from the remains to identify family. ( Matt Bamford )

"Tooth roots and part of the bone around the inner ear tend to preserve DNA really well compared to other skeletal parts, so that's what I sample," he said.

"The remains are still connected to the living people those rangers have family members who were buried in that cemetery, so there is this emotional load that is new to me, and it was very fantastic to hear the stories.

"Each ranger had something to say."

"I don't know of another place in Australia where there has been so many remains unidentified and that have been sampled, so it's really a first."

Flooding, funding obstacles

It is not a given that scientists will be able to find a match.

Decades of exposure to annual flooding and the elements will make the retrieval of usable DNA a challenge.

"This is something that could be a limiting factor, I'm confident that we can retrieve information but it's going to be a challenge," Mr Llamas said.

It is also an expensive process with a further $1 million required to complete the DNA analysis.

Until the money can be raised the bones are being buried again, this time on higher ground, far from the reach of the Fitzroy River.

"They'll be buried with crosses and code numbers on the crosses and on the boxes," Mr Carter said.

For now, many in Fitzroy Crossing are relieved that the remains of their relatives are safe.