The Department of Conservation (Doc) remains unconvinced, while the man who has led efforts to track the elusive mammal for decades is sure the sighting is legitimate.
Dr Norbert Nigon, a veterinarian from Minnesota, said he was hiking the Kepler Track in Fiordland National Park with his wife last week when he spotted an animal he was certain was a moose.
After crossing a suspension bridge as they headed towards Moturau Hut, he spied what he believed was a cow moose - which do not have antlers - standing near a riverbank between 30m and 50m away.
He watched it for about five seconds, before it fled as he reached for his phone to take a photo.
"I’m 100% sure it was a moose."
The animal had a long and narrow face, "big pointy ears", wide nostrils and was coloured a dark brown with shoulders that stood nearly 2m off the ground.
"I thought, ‘well, wow, there’s a moose’."
Moose were introduced to Fiordland from Canada in 1910.
When news of the potential moose sighting became public this week, Doc was sceptical.
Doc Te Anau operations manager John Lucas said it was "extremely unlikely" the animal was a moose, and Doc believed they were most likely extinct in Fiordland.
"I have no doubt Dr Nigon believes he saw a moose, unfortunately without photographic proof, we may never know."
"No photos were taken and due to the location on the Kepler Track, which is a significant distance from where moose were originally released, we are of the opinion the sighting was a red deer."
He added yesterday it could have been a red-wapiti cross.
He acknowledged the area where he saw it was a long way from where moose were released more than 110 years ago, but said they could have migrated that way.
Fiordland moose researcher Ken Tustin said the vet’s account was "absolutely credible".
"I’m 100% happy with it and I’ll be logging it as a record, and there are hardly any records of sightings.
"That’s how much I trust it and trust them."
For most people, the prospect of moose living in Fiordland was "so out of the square it sounds almost ridiculous", Mr Tustin said.
He believed there could be between 20 and 30 moose out there.
University of Otago geneticist and distinguished professor Neil Gemmell said it was "not impossible" there could be a small population of moose still in Fiordland.
In June 2019, Prof Gemmell travelled to Scotland to lead an international hunt for the Loch Ness Monster.
However, the mystery of the Fiordland moose was "not even in the same ballpark".
"Sightings of the Fiordland moose are probably more credible than sightings of the Loch Ness monster, to be fair."
Someone from North America who knew what moose looked like, but may not have any preconceived notions about its rarity in Fiordland, gave the sighting some credibility, Prof Gemmell said.
It would be interesting if moose still existed in Fiordland, but as an introduced species, in a country they were not native to, it would be fine if they no longer did.
"I think it’s neat there’s a few mysteries out there still.
"It gives people a reason to get off their couch and go out into the outdoors and explore it and see what they can find, because there are mysteries to be solved."
