The theft of an emergency locator beacon from an Albert Town camping ground led to two wasted helicopter flights by search and rescue personnel late on Tuesday night.
The beacon's signal was picked up by satellite at 11pm, indicating it was either off the Fiordland coast or somewhere near Wanaka.
A second satellite pass narrowed it down to a location near Luggate.
Rescue Co ordination Centre New Zealand (RCC) spokesman Steve Rendle told the Otago Daily Times yesterday a Queenstown rescue helicopter equipped with night vision equipment was dispatched with a pilot, police officer and medic on board.
Lake District Air Rescue Trust contractor Richard Mills, of Heliworks, said the helicopter picked up a weak signal but was unable to establish the beacon's exact location, and returned to base about 1.30am.
About an hour later, RCC called with updated information and the helicopter flew back to a point about three kilometres southeast of Luggate, and determined the signal was coming from the Clutha River.
Mr Mills said the crew could not see anything from the air so shut down and walked down to the river, where they found the beacon floating in a backwater.
''It was a good find, because we got tasked to find it, and we did.''
Because of the beacon's location, ''bobbing around'' in the water and beneath steep river banks, its signal had been ''fickle'', he said.
He estimated the search required two hours of helicopter flying time.
Mr Rendle said the beacon was among items that had been stolen from the Albert Town camping ground, but he was unsure how it came to be activated.
