A report into the tragic death of a tramper has highlighted the consequences of critical decisions made in mountain terrain, a Coroner has found.

The report released into the death of Takaka woman Tracey Smith found she died from hypothermia while tramping with her son in Nelson Lakes National Park, on Queens Birthday weekend in 2019.

The 55 year-old and her teenage son, who were experienced trampers, had intended going to Angelus Hut, but encountered difficulties in adverse winter weather conditions.

The Lake Angelus basin was a popular backcountry site in Nelson Lakes
National Park. Angelus Hut sat at 1650m above Lakes Rotoiti and Rotoroa in the Travers Range.

Smith suffered from hypothermia and did not reach the hut. Her body was found at Speargrass Valley on June 2.

The New Zealand Mountain Safety Council said the recommendations adopted by Coroner Meenal Duggal highlighted many common factors trampers faced.

The council submitted material to support the coronial investigation, and provided recommendations to prevent future similar tragedies.

The Coroner's report highlighted critical decisions including the choice to proceed to Angelus Hut, rather than back once conditions became impassable. Open Justice has approached the family for comment, but they declined.

Low temperatures, deep snow and poor visibility made things more difficult. Compounding factors were the lack of quality food and rest, and the cotton clothing Smith was wearing directly on her legs.

Mountain Safety Council chief executive Mike Daisley said the tragedy highlighted how small seemingly independent decisions could often compound into a series of errors, each making the situation worse until they become fatal.

"If any one of those critical decisions had been different, Tracey may have survived.

"It's often easy to underestimate the importance of seemingly small decisions. There are lots of little things that can be easily overlooked, and when combined, each of these compound the seriousness of the situation."

The Coroner noted "traps" trampers sometimes made which influenced Smith's decision-making.

Daisley said they were serious yet common traps for trampers, including the tendency to think a situation was safe because others were doing it, and risk-taking which happened when trampers were under time pressures.

The Coroner said Smith had spoken with the manager of the lodge where they were staying before heading off. She was advised that Angelus was not a safe option in the deteriorating weather conditions which included strong winds and temperatures of minus 16C.

Smith decided to hike Paddy's Track up Mt Robert, and stay at the lower Bushline Hut instead.

Smith and her son went to the Department of Conservation Visitor Centre at St Arnaud where they talked about the weather with staff, and told them of the changed plan to hike to Bushline Hut.

Smith had rented personal locator beacons for previous tramps but did not on this occasion, for reasons that were unclear, the Coroner said.

The pair then drove to the Mt Robert car park, where they saw a large group of people hiking to Angelus Hut and made an "on-the-spot decision" to hike to Angelus Hut via the Speargrass Track - a more sheltered route than along Robert Ridge.

After a stop at Speargrass Hut, Smith contemplated staying, but decided to press on in overcast, but not windy conditions, on a track only lightly sprinkled with snow.

An hour into the tramp to Angelus Hut, the snow got deeper, and the
hill was getting steeper. It was cold, snowing lightly, but there was no wind and visibility
was good.

Three quarters of the way into the ascent, by then in deeper snow, Smith's son noticed that his mother had fallen behind. As he waited for her to catch up, the other group carried on and they eventually became separated.

By then his mother was taking small steps and told him that she was experiencing
a lot of leg cramping. She began falling over repeatedly. They were making little progress and Smith's son tried to pull her along with a tramping pole and making the track
easier by moving snow out of the way, but the depth of the snow made this very difficult.

By 5pm the visibility was limited to about 200m, the temperature dropped further,
and the wind increased. The other group reported seeing ice blowing and water bottles hitched to backpacks had frozen.

Given the reduced visibility they were unsure if Smith and her son were still following or had turned back.

By nightfall the wind was strong enough to blow off their head torches. Smith was tired, hungry and thirsty. Their water bottles had frozen. She kept eating snow to quench her thirst, despite her son telling her it would make her colder. Smith was crawling, and her hands started to freeze from being in the snow.

Near the top of the ridge Smith's son realised that she had hypothermia. He tried to warm her and help her in various ways including trying to lift her and removing her pack. He realised that her vision had deteriorated significantly as she could not see the track poles. He wanted to feed her scroggin but his hands were too cold and stiff to open the pack.

Realising that he too was in danger of getting hypothermia, he made the decision
to carry on to the hut, but In the dark, cold and wind, his progress was
painstakingly slow.

He made it to the ridge but could not find the path to the hut, became lost and circled back to his mother, who by then was not moving at all.

He resumed his track to the hut, and despite the challenges he slid over the snow and headed straight for lights he could see. By this point, his legs were cramping, so resorted to crawling to the hut which he reached at 11.15pm.

Confusion in the hut about emergency procedure, among the warden and the party there resulted in emergency locator beacons not being activated as had been discussed. It wasn't until just before 9am the next morning the warden radioed the basecamp at Rotoiti, where staff informed police and a rescue helicopter was despatched to find Smith.

She was found after a brief search and an onboard medic pronounced her dead at the scene.

DoC completed a full investigation following Smith's death, and while it did not identify any issues with its management practices that contributed to her death, it did make several recommendations for system improvements.

The Coroner noted Smith and her then 15-year-old son had tramped together often. In New Zealand, they had hiked the Heaphy Track, Old Ghost Road and the Abel Tasman track several times.

Overseas, they hiked a crater in Hawaii. They were used to high altitudes, but Smith
was not accustomed to hiking in deep snow.