Mr Gale sent one of his helicopters yesterday morning to check if what Australian glaciologist Dr Neal Young saw on a satellite image west of Stewart Island on Tuesday was an iceberg.
His pilot did not see any icebergs in that area, but there was a reef, Mr Gale said.
"It's all information gathering."
National Institute of Water and Atmospheric Research oceanographer Mike Williams said Nasa satellite images on Tuesday showed two icebergs, one about 300km from Dunedin and another 280km away.
Mr Gale said when the icebergs came close to New Zealand in 2006 some never came any closer than 200km.
For safe and economical iceberg flights, they needed to come within about 100km of Otago's coastline.
Companies continued to prepare to take sightseers to the icebergs.
Brooker Travel Group was also planning to offer aeroplane trips to the icebergs.
As it did in 2006, the company would put seats into an Auckland-based mail aeroplane which visited Dunedin daily, for the 50-minute trips.
Not to be outdone, a group of Australians is planning to helicopter out to one of the icebergs, camp on it while they carve out an ice bar, and then stage a party - complete with a DJ who will produce a music track.
Reynold Bierman (38), a Sydney builder, said yesterday his team was still consolidating details of the project.
Glaciologists would make a safety assessment of the potential for their chosen iceberg to suddenly split or turn turtle, he said.
After carving out an "ice bar" inside the iceberg, the men want to fly in party guests for several hours of music and drinks.
One member of the group, Phil Meadows, hopes to create a new entry for the Guinness Book of Records by producing a music track on the iceberg.
The group is negotiating to provide a live feed from the iceberg to an Australian television channel (Channel 9) and is planning internet promotions on YouTube, MySpace and FaceBook, using a satellite telephone.
The group has claimed one part of the project will be to boost awareness of climate change.
But Australian glaciologist Neal Young has cautioned against linking the appearance of the icebergs in New Zealand waters to global warming.
He said the phenomenon depended as much on weather patterns and ocean currents as on the rate at which icebergs broke away from Antarctic ice shelves.
Three years ago, a flotilla of icebergs - including one 1km long - drifted towards the Otago coast, with some coming as close as 25km to land.
This had not happened since 1931.
