Police say they hold "grave concerns" for missing tramper Alistair Levy after a third and fruitless day of searching ended.
The 54-year-old Palmerston North High School teacher went missing after reaching the summit of the peak in Kahurangi National Park on Sunday.
Seven ground teams searched the park at the top of the South Island for a third consecutive day today, but found no trace of Levy.
The ground search will now be stepped down although police have asked a group of cavers heading into the area tomorrow to keep an eye out.
Search coordinator Sergeant Mike Fitzsimons said police held grave concerns for Levy's welfare given how long he had been missing and the rough terrain in the park.
A further aerial search is planned for tomorrow, after which options will be reassessed.
Levy sent a text message after reaching the 1875-metre summit, but has not been seen or heard from since.
He had planned to join wife Tracy and other family members in Christchurch for Christmas.
Yesterday, his bicycle was located at the cafe at Kohatu, where Mr Levy had arranged to leave it with the cafe owners.
Cafe co-owner Graeme Crook said today he could not remember when Mr Levy dropped off the bike, only that he had been in one morning recently.
Crook contacted the police yesterday to tell them that the bike was at the cafe.
"We were really busy when he came in. A lot of people leave bikes and cars here. Sometimes I have eight, nine or 10 cars."
Levy was believed to have been carrying a purple and black backpack, but did not have an emergency locator beacon with him.
Search and Rescue coordinator Sergeant Mike Fitzsimons said seven teams were searching today after four teams spent last night in the field. By that time, the area would effectively be covered, he said.
Searchers would be dealing with intermittent rain and rugged country.
"It's a big mountain, and it goes from being awesome to scary, depending on where you are."
Searchers still thought Levy walked over the top of the mountain and had planned to come back via the cafe, Fitzsimons said.
The discovery of his bicycle had confirmed this view.
Brother Graham Levy said this morning that his brother had been tramping for 30 years, but it was not unusual for him not to take an emergency beacon.
He had been progressively tramping through the entire South Island, from north to south, and the Mt Owen trip was to fill in a gap in that process.
Nelson Speleological Group president Andrew Smith said people travelling on the south side of Mt Owen "absolutely" needed their wits about them.
Smith said the group had been asked to help with the search, and a caver was on the mountain advising the police.
"It's not too bad a country to find your way through if you know where you're going, but if you don't, it's tough."
He said the area was one of only two places in the world with glaciated marble, and this made it very attractive to trampers.
"The Lord of the Rings [producers] knew what they were doing when they took their movies up there."
"It's not like another area in New Zealand. It's not just a normal tramping area."
The terrain included marbled slats and lots of holes, from one metre in diameter to much larger.
"Some go down only a few metres, but some go down quite a bit more." There were also sharp edges in some areas, which was quite concerning, he said.
"Even just a simple fall could injure him quite easily."
Route finding was also extremely difficult, and it was quite easy to get lost, even in such a small area, Mr Smith said. Maps of the area showed only 20m contours.
"There's a lot that happens within 20 metres that can't possibly be shown on a map."
The weather was also as variable as in any other alpine area, but Mr Levy would at least have warm temperatures and a variety of possible shelters on his side, he said.
The difficulties with the south side of the mountain were not widely known, as the north side was an easier route, Mr Smith said. But experienced trampers would take an emergency beacon if they were in an area they did not know well.
"In this situation, he should have a beacon with him.
"All it takes is for you to fall over and break a leg."
Often, trampers decided not to make the trip after doing research, he said.
Anyone with information about Levy is asked to phone the Nelson police, 03 546 3840.
- © Fairfax NZ News
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