A snow-blind 27-year-old Canadian man was rescued from Mt Aspiring yesterday after his father in Australia alerted Wanaka police that he seemed to be in trouble.
The man's father was watching his son's progress on the mountain on Friday night via an internet global positioning system service called Spot Tracker.
Wanaka Senior Constable Emma Fleming said the man had reached the summit of Mt Aspiring alone on Friday. But about 10pm his father alerted Wanaka police that his son had not moved for five hours.
Ms Fleming said bad weather prevented any attempt to rescue the man that night.
At noon on Saturday the man hit the "help" button on his GPS device.
Using the Spot Tracker data, police could see he was moving backwards and forwards in a small area near Mt French at the end of the Bonar Glacier but he had missed the "exit point" on the descent and was clearly lost.
"He had become stranded in bad weather and couldn't negotiate his way down initially because he was lost but then subsequently, having dug himself a snow cave, he became snow-blind," Ms Fleming said.
"So there was no way he was going to be able to get himself out."
Ms Fleming said the man knew the police were searching for him because he heard the helicopter.
Then early yesterday as weather improved the helicopter and Land Search and Rescue team carried out a "snatch and grab" to lift the man to safety.