Rakiura/Stewart Island may have had its own moa population

New research suggests Rakiura/Stewart Island once had a local population of Aotearoa's long-lost giant bird, the moa. Image / Paul Martinson

Rakiura/Stewart Island may have had its own population of moa, a new study finds.

The paper, published in the New Zealand Journal of Ecology outlines the results of an analysis of a moa skeleton discovered on Rakiura's West Ruggedy Beach, by Department of Conservation (DoC) Rakiura ranger Phred Dobbins.

"The excavation revealed a partial skeleton with no cut marks from stone tools, and we also discovered gizzard stones and a dark organic-rich layer of sand beneath the skeleton that was likely stained by the rotting moa and the plant contents of its gizzard," said the study's lead author Dr Alex Verry, of Otago University's Department of Zoology.

Ancient DNA analysis revealed that the skeleton belonged to a South Island giant moa, while radiocarbon dating showed the moa died around 700 years ago, just after the arrival of Polynesians on the island.

Co-author Dr Nic Rawlence, director of the Otago Palaeogenetics Laboratory, explains ancient DNA analysis revealed that the skeleton belonged to a South Island giant moa (Dinornis robustus), while radiocarbon dating showed the moa died around 700 years ago, just after the arrival of Polynesians on the island.

"The findings suggested the South Island giant moa had died near to where it was found and represented a moa that naturally occurred on Rakiura and died a natural death," said study co-author Dr Nic Rawlence, of the Otago Palaeogenetics Laboratory

"We believe it is likely to be of natural origin, despite its post-human date."

The research team excavated the skeleton with the assistance of DoC senior heritage advisor Dr Matt Schmidt, in close consultation with Murihiku Ngāi Tahu, kaitiaki and mana whenua of Rakiura.

Schmidt said the discovery that this species of moa was alive when Māori first occupied Rakiura has significantly added to the cultural narrative of the island.

"The find emphasises the important link between the natural and cultural heritage values on Rakiura and that continued research like this is invaluable for understanding the island's past and informing on its future management."

Verry said the research highlights the scientific significance of such remains and their ability to provide unique insights into the past.

"A large amount of important contextual information is lost when individuals take it upon themselves to remove moa remains from protected areas like national parks and archaeological sites, in order to sell them.

"Without this appropriate contextual data, these remains become near scientifically useless."

The research also highlights the importance of scientists working with iwi, particularly given moves to stop the removal of moa bones from archaeological and fossil sites to sell online.

The Government is now considering banning the sale of subfossil bird bones, including moa, in New Zealand.

Rawlence said that, if the sale of moa bones is stopped, then discoveries like this South Island giant moa on Rakiura may help answer important questions about the evolution of the long-lost bird.