Craigieburn Range moa sighting and photograph (Freaney, Rafferty and Waby), 1993

Moa were New Zealand's giant flightless birds. Te Ara states that "there is no convincing evidence that moa have existed since about 1550." Yet reports kept surfacing, from the 1860s gold rush up to 1963.

Paddy Freaney knew rough country. A former British Army SAS sergeant-instructor and well-known mountaineer, he came to New Zealand in 1969 and later built the Bealey Hotel at Arthur's Pass.

20 January 1993. A Wednesday. Freaney set out early with Rochelle Rafferty, who worked for him at the hotel, and Sam Waby, a Christchurch schoolteacher and deer stalker of 30 years. They hiked into the Craigieburn Range, in the upper Harper valley, about fifty miles west of Christchurch.

Then they saw it. The witnesses put it at about six feet tall, roughly three feet from the ground to its back, with a neck about three feet long ending in a small head and beak. Reddish brown and grey feathers covered the body except the legs below the knees. Freaney said it was larger than any emu he had seen in Australia. Waby carried a rifle. "I didn't even raise the rifle, because we were that bloody dumbfounded. It looked straight at us, and then it was off."

The animal fled across the river. Freaney dashed after it and photographed it at 35 to 40 metres. On a riverbank rock he found an apparently wet three-toed footprint, and photographed that too. "We were sober as bloody judges," he said. "We'd have been quite lucky if we'd had two bloody pints."

The photograph ran in newspapers across New Zealand. It showed a shape amid the brush. Out of focus. Partly lost in shadow. Image-processing staff at the University of Canterbury spent three days on the negative. Supporters say they found no tampering and a large brownish-grey bird. Others called the enhancement inconclusive.

The Department of Conservation announced a search for tracks, feathers and droppings. Then it cancelled it. It said the full sequence of negatives was never supplied. The Canterbury Skeptics met all three witnesses. Denis Dutton noted their "coherence, consistency and sense of sincerity". The options, he wrote, were "a hoax, a moa, or something else". Finding the first two unlikely, he was driven to the third.

Richard Holdaway, then a University of Canterbury zoology postgraduate, said it was a red deer. The neck, he argued, was too thick to belong to a bird. Waby and Rafferty insisted it was unmistakably not a deer. Earl Swift of the Virginian-Pilot hiked to the site and found nothing. He listed the doubts: blurry photos, a "suspiciously perfect" footprint, publicity for the Bealey Hotel, and no later sightings in a valley full of hikers. Freaney strongly denied any hoax. He held to his story until he died of cancer on 29 March 2012.

The sighting set off the moa mania of 1993. Radio hosts flew in by helicopter with plastic rifles as moa hunters. Freaney did not find it funny. Bruce Spittle gave the case the largest single section of his three-volume Moa Sightings and found no evidence the witnesses were other than genuine. In 2013 Rochelle Rafferty, who had married Freaney, carried his ashes to the summit of Everest.