A decision is yet to be made on whether to return rescuers to the remote Raoul Island to search for the Department of Conservation worker missing since yesterday's volcanic eruption.
Five DOC workers were rescued from the island, 1000km northeast of Auckland, when the volcano began erupting from a crater lake but one worker, who had gone to the lake to check temperatures was still missing.
A long-range helicopter flew to Raoul Island yesterday and rescued the three men and two women but DOC said today no decision had yet been made about mounting a rescue mission for the missing man.
DOC spokeswoman Liz Maire said today the fate of the man was not known.
The helicopter made a brief search of the crater lake area for the man but found no sign of him.
Ms Maire could not say when a decision would be made.
"There will be further discussions today between the police and the Department of Conservation then hopefully a decision will be made."
She was asked why there appeared to be a lack of urgency about making a decision on a rescue mission.
"With this being such a remote site and potentially a site which is unsafe, we need to be very cautious about sending anyone into the area. That is why we evacuated those five people as soon as we could.
"That is why no rushed decision is being made."
She said the possibility the missing worker lying injured and in need of help was taking priority in discussions.
Conservation Minister Chris Carter said this morning he believed the missing worker almost certainly dead.
Mr Carter said the chances of finding him alive were virtually nil - possibly one to two per cent.
Mr Carter met the rescue helicopter when it landed at Ardmore Airport in Auckland late last night with the survivors.
"There is always hope he might be alive but the police officer briefing me last night informed me that his professional view as a search and rescue officer as well as a police officer, was that there was a very, very limited chance of any surviving.
"In his view there was a one to two per cent chance, that was all."
Mr Carter said the missing worker was at the lake when it erupted.
"He was at the exact epi-centre of the massive destruction, including where five metres of ash fell."
He said as minister of conservation it was a very sad day to have lost a staff member which is why he flew to Ardmore yesterday to meet the survivors when they returned.
"They were very traumatised as one would expect. There has been only the six of them on the island since last October.
"There is a very close friendship in this small group. They are like family members."
Ms Maire said the long flight to the island was one of the factors being considered in plaaning a rescue mission.
"We have to balance out that it is a remote site and people going into that area need to be sure they are going to be safe first," she said.
The missing man, in his 30s and had gone to check water temperatures in a crater lake, on the volcanic island when the crater erupted.
Two DOC workers search for him but turned back because the track was impassable and there was further volcanic activity.
The worker did not answer calls on his radio.
The aerial search lasted about 45 minutes.