A type of beaked whale species has washed ashore in Otago - and it is so scarcely seen, scientists say it could take weeks to confirm its DNA.
The Department of Conservation said its staff were told a whale about five metres long had washed ashore near Taieri Mouth on 4 July.
After inspection and consultation with marine mammal experts from DOC and Te Papa, it was believed the creature was a male spade-toothed whale.
Coastal Otago operations manager Gabe Davies said if confirmed, it was a very significant scientific find.
"Spade-toothed whales are one of the most poorly known large mammalian species of modern times.
"Since the 1800s, only six samples have ever been documented worldwide, and all but one of these was from New Zealand. From a scientific and conservation point of view, this is huge," he said.
The species was first described in 1874 from just a lower jaw and two teeth collected from Pitt Island, Rēkohu (Chatham Islands), Davies said.
That sample, along with skeletal remains of two other specimens found on Whakaari/White Island and Robinson Crusoe Island, west of Chile, had enabled scientists to confirm a new species.
Two more recent findings, in Bay of Plenty and north of Gisborne, helped describe the colour pattern of the species for the first time, he said.
A specimen this fresh offered the first-ever opportunity for a spade-toothed whale to be dissected, Davies said.
Genetic samples had been sent to the University of Auckland to curators at the New Zealand Cetacean Tissue Archive.
It may take several weeks or months for the DNA to be processed and a final species identity to be confirmed, Davies said.
"The rarity of the whale means conversations around what to do next will take more time because it is a conversation of international importance," he said.
The whale appeared to have died either on the day or a day or two before it was found, Davies said.
"It's bittersweet that it wasn't alive and we couldn't study it in its alive state but the next best is a fresh sample like this. At this stage, we don't know what was the cause of death," he said.
Spade-toothed whales were listed as data deficient in New Zealand, and it was hoped this whale would be able to help fill some gaps, such as what the species typically eats or where it lived, Davies said.
Since the finding had been announced, interest had come flooding in from around the world.
Davies said it underscored why it was important for members of the public to report wildlife they see to DOC as soon as possible.
"We're really appreciative of fast communication and great quality photos. That's always a really helpful part, as well as identifying on GPS where the location is so we don't have people scouring beaches for hours."
The whale was currently being kept in a commercial cold store in Otago.
"It can't stay in that cold store forever and [if it did] it would be a missed opportunity. There's many moving parts to this, such as things like funding of that science and research, location... we're just taking it bit by bit," Davies said.
Balancing science and research equally with te ao Māori was important for DOC, he said.
Te Rūnanga ō Ōtākou had been engaged since the whale sighting was reported, and the hapū wanted to help support further research, while seeing that matauranga Māori was upheld, Davies said.
"Something that is quite commonly requested because of the significance of whales within te ao Māori, specifically the jaw bone is quite a common request."
It was hoped a hui would be held with all the various interested parties to decide on the next steps in the coming weeks, he said.
DOC had been working in partnership with Te Rūnanga ō Ōtākou from the outset on making a plan for the whale's remains.
"It is important to ensure appropriate respect for this taoka is shown through the shared journey of learning, applying mātauraka Māori as we discover more about this rare species," Te Rūnanga ō Ōtakou chair Nadia Wesley-Smith said.
The whale had been carefully removed from the beach by local contractor Trevor King Earthmoving, local rūnaka members and Otago Museum.
It was now being preserved in cold storage until the next steps were decided.