Moa find on Manawatu Tararua Highway project could be thousands of years old

Palaeobiologist Dr Richard Holdaway discussing the moa bone sampling process with Te Ahu a Turanga kaitiaki Terry Hapi at Te Manawa in Palmerston North. Photo / Supplied

Evidence of moa found during excavation work on the Te Ahu a Turanga- Manawatū Tararua Highway last year could potentially be more than 180,000 years old.

However, that was still dependent on the completion of analysis, which was still months away.

It was a find that, in the words of palaeobiologist Dr Richard Holdaway, was "serendipitous".

The adjunct professor at the University of Canterbury said he had seen an instance at a major site in the South Island - a farm pond - that had been mostly destroyed by a digger.

"Usually, it's serendipity on the end of a very large digger bucket. And someone with sharp eyes. And a feeling that it's important."

One of the bones found last year on Te Ahu a Turanga: Manawatu Tararua Highway project. Photo / Supplied

What Holdaway found remarkable about last year's find was that it was unique.

"It's a fauna," he said. "There are two species of moa there, two separate genera."

There was also an extinct predator as well as bones of the North Island extinct goose.

One of the pieces found was a thigh bone about 3cm long, indicating it was a hatchling, so there were hatchlings as well as adult moa.

The professor, who has more than 30 years' experience in the field, said that showed how amazing the deposit was.

"I've had several finds in my time, but this is well up there toward the top."

Waka Kotahi owner interface manager for Te Ahu a Turanga, Grant Kauri, said the find was significant for all the stakeholders involved in the project to build the new highway.

He said for those on the project it was an "extraordinary find and a real credit to our people on site and the processes that we have in place".

When the discovery was made, they had a kaitiaki on site immediately who could facilitate the process of not only the find, but in helping to bring in an archaeologist and experts like Dr Holdaway.

Grant Kauri is grateful to iwi who were able to help facilitate the process of preserving the extraordinary find. Photo / Supplied

"Our iwi – they were the voice to facilitate this discovery, hold up mana and the wairua around this process as well," Kauri said.

Those working on preserving the fauna were careful to observe all the protocols around tapu as well, with the kaitiaki able to help them navigate their way through that, he said.

"Having our kaitiaki and our iwi support through this process has been huge."

The deposit was taken to Te Manawa Museum in Palmerston North for safekeeping until an agreement was made with iwi to take samples that could be studied so the age of the fauna could be determined.

Holdaway said the bones found were even more important because of the potential age of the deposit.

"In my 35 years, the oldest bones I've been looking at in a fauna is 40,000-50,000 years old."

However, he stressed it was early days in the analysis and he would not be able to confirm all the findings for several months.

He said the minimum date from analysis of the sediment at the Luminescence Dating Facility at Victoria University of Wellington was potentially 180,000 years old.

"However, the bones themselves may be much older."

A PhD student, who was a volcanologist, thought the bones might be sitting under volcanic ash.

They were now working to identify whether it was an ash layer, but if that were the case, it would have probably been from a major eruption, or rather a super-eruption.

Holdaway said the only eruption of that magnitude was about 345,000 years ago, when "there were no homo sapiens on this planet. We hadn't evolved yet".

While there were moa bones dating back to 1 million or 2 million years ago elsewhere, they were individual bones.

"This is clearly a fauna – more than one species. And the bones are exquisitely preserved. That in itself is extraordinarily unusual."

It was also hoped a researcher at the University of Copenhagen could extract DNA from each of the adult moa.

Holdaway said if that were possible and it was sequenceable - and they were indeed as old as he was thinking - researchers might be able to see in real time the genetics of those moa.

"Where now we're only able to conjecture back. So this, potentially, is a whole lot of windows into the past, but a lot of them might be broken and the shutters might be up."

He said he was learning all the time from this find.

"No one else in New Zealand has ever worked on a deposit like this before, so I'm taking it carefully."