Seven ancient moa footprints have been discovered at the bottom of a river in Maniototo.
The 30cm-wide imprints, found by a tractor driver taking his boss' dogs for a walk along the Kyeburn River, are the first-ever found in the South Island and believed to be possibly millions of years old.
"It's pretty cool to find something different," Michael Johnston told Newshub. "To later on find out they're the only ones to be found in the South Island is pretty cool, in a wee place like this."
Otago Museum assistant curator Kane Fleury said it was the kind of discovery that would be the highlight of a scientist's career.
"I'm only young, so hopefully there's some other things in the pipeline, but this is amazing," he told The AM Show.
The prints will undergo conservation treatment and will eventually be displayed at Otago Museum.
"The job to extract those is pretty huge - it involves the diversion of a pretty major river," said Fleury. "They're currently located still this morning under about a metre-and-a-half of water, until we pump out the swimming hole."
He said the bird that made them would have been large.
"Moa range up to about 250kg... they were big, big animals. Big, big fleshy thighs on them."
Fleury said this one wouldn't have been quite that big, and was likely an ancestor to the huge birds that came later.
On finding the prints, his first job was to establish whether they were real.
"I wouldn't expect that someone would be able to fake these, especially with the erosion that's occurred to quite a few of them. There's no chance."
Then he had to rule out the possibility they were made by an everyday emu or ostrich.
"Initially I was thinking of the other large birds in New Zealand - there's a few ostriches and emus around. I was thinking, does it match those? The toe length is different, so it doesn't' work out with those. So once you go through all of the things it could be, it kind of leaves what it is."
Like a dinosaur?
"It definitely wasn't a dinosaur because the formation's way too recent for that," said Fleury. "We're kind of left with a big bird - and if you're familiar with New Zealand birds, you know that the moa was a prime contender."
Most moa bones recovered so far date from after the last ice age - so less than 12,000 years. The prints in Kyeburn date back millions.
"This is a pretty important find for New Zealand."
Sadly, the find won't help MP Trevor Mallard's dream of bringing back the moa, with recent research suggesting even reconstructing the bird's DNA won't be enough.