All it took was a wrong turn. Madeleine Nowak was the straggler on a day hike with her partner and friends when she came to a huge fallen tree blocking her track. She tried to scramble over it but couldn’t. She tried to go around it – just a quick detour – but when she got to the other side, the track was hidden under leaves. Where had it gone? The path must be nearby. She trudged a bit. A bit further. Suddenly, she was deep in the forest.

“Coo-ee!”

Silence.

“Coo-ee!”

Nothing.

Madeleine, then 73, had always had a lousy sense of direction. An amateur photographer, she’d amble behind her companions on hikes, snapping birds and plants. Her friends and her partner, Clive, knew she was a dawdler; Clive was used to backtracking to find her on walks. On this afternoon on the Queensland island of K’gari, formerly Fraser Island, she was convinced he’d hear her. When nobody did, she kept walking, doing that fateful thing anyone with a poor sense of direction does: “I guess I followed my nose.”

The afternoon turned to night, the night turned to day. Still nothing. By now, emergency services were combing tracts of dense ferns and towering satinay trees for Madeleine. But she was on the move, bashing through the bush in search of the coast.

Around 38,000 people go missing in Australia every year. There are many reasons: domestic violence, health conditions, simply failing to tell anyone where they are. In about 3000 cases a year, coordinated search and rescue operations are required. About two-thirds of these are at sea; those on land might involve people injured, bogged out of reach of help, or lost. Often they’re found swiftly, but occasionally, they’re not – and every passing hour can lessen their chances of survival.

How do people get lost? What should you do if it happens? And how do search parties find you?

Who gets lost?

When following her nose failed, Madeleine tried to correct her course. She walked uphill to try for phone reception or to spot a landmark, but at the top, there was no signal, and the rainforest was thick in all directions.

Oh dammit, now what have I done? She recalls thinking. How am I going to sort this?

“Once you leave a track,” says Jim Whitehead, who was involved in the search for Madeleine in September 2020. “Unless it’s really well-worn, they’re very hard to see from a few metres away.”

Whitehead is no stranger to the bush. “I used to bushwalk in the younger days,” he says. “I’d never tell anybody where I was. I did all the things I tell people not to do now.” He wrote the manual on search and rescue protocols used in Australia and estimates as co-ordinator for Queensland Police he was involved in about 24,000 search and rescues, known as SARs.

When he started in the force in the ’80s, “people said there would [one day] be no ‘S’ in SAR,” he says. “It would just be a rescue because we’ll know exactly where they are. Forty years on, yes, we do have GPS as we have locating beacons; we have a tonne of electronics. But, basically, it still comes down to someone searching for a missing person. We haven’t actually got to the stage yet where we can just find somebody by hitting a button ... it’s still very manual.”

“No one knows about you unless someone comes across your car.”

It’s novices who typically get lost in the bush, he says. “They’ve got no map, they’ve left at midday in a pair of thongs and shorts, and [they don’t realise they] are never going to make the return journey before the sun sets.”

Another search veteran, Rod Costigan, agrees. “It will not be the walk leader or the guy who said, ‘Come camping with me’,” says Costigan, who leads the volunteer Bush and Search Rescue Victoria, which helps police. “The person who is lost alone, overnight, will usually be someone who came along but got separated.”

Dependents are especially likely to stray. “For the adventuring types, there are plenty of sources of advice as to how to be prepared,” he says. “But if you are taking kids for a picnic in a country picnic ground or taking your elderly parent for a short walk near your bush block, you won’t be thinking in these terms.”

People who rely on unofficial maps and trails are also prone to losing their way. In NSW’s Blue Mountains, for example, these tracks are not maintained and can be difficult to follow. Most are marked with signs to discourage people from taking them. “Unfortunately, those signs don’t always stop people,” says Sergeant Dallas Atkinson, who leads the Blue Mountains Police Rescue unit. A 2023 study of lost people and search and rescue cases found men were more likely to leave a path when lost while older females were more likely to be found closer to one. (Madeleine was an exception: “I kept going,” she says, “I’m not afraid of being on my own.” )

It’s not just trekking on foot that can spell danger, but being bogged in a car beyond mobile range. “No one knows about you unless someone comes across your car,” says Whitehead. In May 2023, Melbourne woman Lillian Ip’s car became bogged in Victoria’s High Country without phone reception, and she was unable to walk for help.

Police searched for five days until they saw her from the air. Lillian, a teetotaller, had no water but survived on lollies and taking sips from a bottle of wine she’d planned to give to her mother. (An expert we spoke with said alcohol was not the preferred drink to prevent dehydration, but it could extend survival time.)

Then, there are the cases where satellite navigation (GPS) sends drivers down unmaintained roads. In February, a bum steer from Google Maps got two German tourists driving in Queensland’s far north stuck on a muddy track. They walked 60 kilometres with heavy packs before emerging a week later in Coen, population 320.

The ocean brings its own complications. An angler in a lifejacket might be swept off rocks, a jetski broken down without navigation equipment, or a boat overturned in dwindling light. From the air, a person is a fleck on the surface as currents and wind carry them from their last known location. “The ocean is often very featureless, so it’s an intensive activity to try and look for targets,” says Rick Allen of the Australian Maritime Safety Authority.

In about a quarter of search and rescue cases on land, the lost person has dementia, Whitehead says. “They might walk out of a house or walk away from a shopping centre … [It’s] very hard because they often don’t know they’re lost.“ One woman with dementia hid in cane fields north of Mackay for three days in 2020. “We couldn’t find her by thermal imaging because she was covered in mud, we couldn’t find her by searching because she would deliberately hide.” Luckily, a truck driver spotted her on the side of the road and alerted the police, who shifted the search. “It was only because we saw the cane bend down from the air that we found her.”

How do we know if we’re lost?

As a teenager, Madeleine would lose her way on shopping trips: “Where on Earth am I? Which door have I come out of?” On holiday in Athens in her 20s, she misread a map and ended up an hour from where she wanted to be. “I stopped and asked someone, and they pointed me in the right direction.”

Humans’ internal GPS systems recruit several brain regions, particularly those involved in spatial memory, such as the hippocampus and entorhinal cortex, to build mental maps. “It’s the ability to have a sense of the surrounding environment as a two-dimensional representation,” says Don Montello, a researcher of lost person behaviour at the University of California. “That’s what allows creative navigation, shortcutting and is tied to maintaining orientation.” The snapshot will include landmarks. When travelling, for instance, “I want to know which direction the front of my hotel is facing. Even large macro features like, where’s the Seine in Paris?“

As with any skill, how well people navigate depends on innate ability – but practice helps. Before London taxi drivers can drive a black cab, they sit a test called “the knowledge”, proving they’ve memorised hundreds of routes as well as streets and landmarks. One study of 16 drivers found they had larger hippocampuses than people who did not drive taxis. The effect increased for those who had been in the job longer.

Being lost involves being in a state of uncertainty, says Montello. “There’s degrees: I can have no idea, or I can think I know [where I am], but not really be sure. Those are on a spectrum. But they’re all examples of being lost.” Whitehead offers a simple test. “When you can’t actually point on a map to see where you are going, you’re lost.” Still, he says, most people don’t want to admit it. “We all want to appear to people that we know what we’re doing.”

Madeleine’s partner, Clive, has a good sense of direction, she says. “Because I’ve basically relied on him for 45 years, I’m worse.” She can’t point out which way north is, for example, although she’s not at a complete loss. “If I can see the sun come up, then I know that’s east.”

What should (and shouldn’t) you do if you’re lost in the bush?

Clive took what he describes as a “cold” approach after he realised Madeleine was missing from the K’gari track. As a scientist, his way of dealing with things, he says, is not to get caught up in emotions. He couldn’t call triple zero without reception, so he backtracked, yelling Madeleine’s name. Two friends also on the hike raced to find a driver who earlier that day had dropped the group at the track. They picked up Clive, and he called the police. “There was anxiety,” he says, “but it was more, what are the best things we can do to get this sorted out?”

Before sunset, Madeleine found a hollowed-out tree to spend the night in – with no torch, she needed daylight to see. She rummaged through what she had: walking poles, a raincoat, a pear, boiled eggs, rice crackers and cashews. She had water to last 2½ days. “I started rationing,” she says. The island is home to about 200 dingoes that roam in packs – she wrapped her backpack tight and left it 20 metres away so any scent from it wouldn’t draw animals to her.

Unlike many people who get lost, she had several essentials to survive a short time. Being prepared for the worst can be lifesaving. One item she didn’t have was a personal locator beacon. When activated, the device, about the size of a matchbox, sends a signal to satellites that alert stations across Australia and surrounds. The beacon is registered before you set off: it lists contacts both for the owner and for someone who knows their plans and can share trip notes with searchers. “The best thing about them is they are not reliant on a telephone or internet connection,” Whitehead says. “It’s probably the best tool you’ll ever buy.”

Phones can feel like a GPS in your pocket, but they offer a false sense of security. Keith Muller, a deputy controller in Victoria’s SES, works on searches in the Werribee and Lerderderg Gorge areas, where he says most walkers assume they’ll have phone (and internet) reception. “Both the Werribee and the Lerdy, believe it or not, there’s hardly any emergency radio reception, let alone phone reception.” What’s more, “when your phone can’t get reception it chews up the battery really quick.”

Lost people in the Blue Mountains are often able to call the police. Sergeant Dallas Atkinson says his team will coach them through using their phone to find their longitude and latitude. “They might not know where they are, but we can determine exactly where they are and send a team in to get them.”

Madeleine’s phone momentarily worked on the first night. She texted Clive:

Then her phone went flat.

Being lost didn’t send her into a panic, but she was irritated with herself for worrying Clive and her friends. I’ve stuffed everybody’s holiday, she thought. Determined to fix things, she lined up trees with the sunrise to go east and off she went, into waist-deep scrub where her walking poles were all that stopped her from falling over. I just need to keep myself safe, she kept thinking.

“Do nothing until you actually hear searchers come. If you’re lost, you’re lost. Don’t make it harder by trying to un-lose yourself.”

Trying to find her own way out was the wrong decision, she says now. Every step took her further from searchers. Whitehead says people who are lost should find shelter and “do nothing until you actually hear searchers come”. In other words, stay where you are. “If you’re lost, you’re lost. Don’t make it harder by trying to un-lose yourself.”

Madeleine could hear helicopters scanning for her. She found a clearing and waved her poles in the air. “They weren’t close enough to me. In fact, they didn’t go over me,” she says. It’s a common enough scene in TV dramas – the person madly waving to no avail because the pilot can’t see the trees, let alone the person under them, for the forest. If she’d known, Madeleine might have used her phone screen to reflect the sun to signal to the helicopter. (The lenses of spectacles, reflective blankets or surfaces on vehicles can also work, while police night vision picks up torches or phone lights.) Today, she also carries a battery pack to keep her phone charged and would switch off her phone if there was no reception to conserve power.

Sometimes, lost people clear an area and write a signal with rocks or branches. In 2020, three men were found marooned on a Micronesian island after writing SOS in the sand. “To do something like that, it needs to be in letters about 10 metres long because little letters don’t show up from the sky,” Whitehead says.

One of the biggest factors in a lost person’s survival is access to water. People can generally survive weeks without food, says Dr Paul Luckin, a medical adviser to search and rescue teams across Australia. “But to survive on no fluid at all, you are generally looking at about three to four days,” he says. “If you’re in an arid environment in the west Australian desert, on the worst of the hot days, you might need to be drinking towards a litre an hour.”

Despite some TV shows fuelling the myth that people can drink their own urine, Luckin says the body’s waste will make dehydration worse. “Drinking urine is a negative gain.” Seawater has a similar effect, and the salt also affects brain function. “It’s characteristic of people in the lifeboat who eventually drink seawater that they’re described as going mad.”

Madeleine, a dietitian, knew how important water was. “I had frequent, very small drinks; just a mouthful to keep going.” She even licked leaves from branches on the third day to get extra fluid. “I thought, now, there’s a risk of infection here; however, I reckon I’ll be out before it manifests.”

How do searchers find a lost person?

By Madeleine’s third night in the bush, Clive was increasingly worried. He thought she should already have reached the coast. “I was quite depressed, quite sad, quite tearful,” he says. “Friends were plying me with gin and tonics and trying to keep me happy, but then you’re on your own. You’re sleeping in a bed, and the bed is nice and warm. And your mate, your partner, is somewhere out in the bush.” He offered to help search. “Their reaction was, ‘We’ve lost one person, [we] don’t need any more.’”

There were about 60 people looking for Madeleine. Whitehead didn’t expect her to be walking for so long. “The 70-year-olds that I know don’t do that.”

Searchers generally start from the lost person’s last known location: a car parked at the entrance of a national park or a sighting along a trail. This is why telling someone where you are going is crucial. If you haven’t, says Caro Ryan, a search commander from NSW SES, then “[we] are starting with such a massive landscape area”. Police circle the point on a map with a radius indicating how far someone could have walked. “If everything is perfect, you have to be inside that circle,” Whitehead says. Generally, people walk downhill. “Most people will get fatigued and won’t try to fight the environment.” Police also note valleys they could be stuck in, where there’s water, fences or roads they might follow.

Searchers call out the lost person’s name. “We’ve done tests in our unit of the female voice versus the male voice. Usually, we would use the female voice.”

It’s similar at sea: rescue crews will “box up” an area where they believe a lost person might be. “Sometimes we’ll have a last known position, sometimes we’ll only have a route,” says Allen from the Australian Maritime Safety Authority. Using ocean modelling and sometimes buoys tracked at sea, Allen’s team will predict how far a lost vessel or person in a lifejacket could have drifted. Sometimes, as many as 12 aircraft search at once.

On land, it can be as simple as following the path the person was meant to be on or using a helicopter or drone to scout for them. “We’ve had a number of operations resolved very quickly by launching a drone and being able to spot the person from the air, get an exact position of where they are and saying, ‘We know where you are, we’ll come and get you’,” says Atkinson of NSW Police.

If police find no trace, they call for backup – volunteer groups help scour off-track, and detectives explore possible scenarios, checking traffic cameras, dashcam footage and security cameras and looking for shoe prints. Sometimes, dogs will help, particularly when people with dementia can wander in any direction. “[The dog’s] sense of smell is significantly more sensitive than ours,” Atkinson says. “A dog and a handler are partners, they get to know the dog for years, and those subtle cues that the dog is giving them.”

In dense bush, searchers work in teams spaced out in a row, periodically stopping to listen and calling out the lost person’s name. “We’ve done tests in our unit of the female voice versus the male voice,” Ryan says. “Usually, we would use the female voice. The high voice seems to carry further.”

How do searchers know when to stop?

Paul Luckin first helped to rescue people – often tourists stuck down cliffs on the Derwent River – when he was a paramedic in Hobart. Later, he was training as a specialist in anaesthesia in South Africa, treating victims of knife crime and bombings, when his superiors tapped him on the shoulder.

“The boss received a phone call from the convener of the mountain rescue team, who said we need a doctor with experience in trauma and some knowledge of rescue, and they said, ‘Well, I’ve got a boy from the Antipodes here who is just what you need.’”

Near the hospital where Luckin worked, police would sometimes clear the highway for a helicopter to land so he and his team could fly to remote peaks, as high as 10,000 feet in the Drakensberg Ranges, to retrieve lost or stuck mountaineers or victims of plane crashes. He’s also been an anesthetist in the Australian Navy, treating war casualties in Afghanistan.

Today, his job is to estimate the survival time police have to work with in any given search and rescue case. “When they phone me and say, ‘We’re up to our backsides in the snow’ I understand because I have been in exactly that circumstance. When they phone me and say they are in an arid environment, I understand because I’ve been in exactly that circumstance in Afghanistan [and] training in Kuwait where it’s 54 degrees.”

“There was no surface water in the area. I thought the probable end of her timeframe for survival was the end of the day on Sunday.”

Someone’s chances of survival are largely based on the conditions, the person’s physical and mental state, and their access to water and shelter. In Madeleine’s case, Luckin estimated water was the factor that could limit her chances of survival. “There was no surface water in the area; a sandy base, so there was no possibility of water collecting.” He was told she only had half a litre of water, so he estimated she would be severely dehydrated 76½ hours after she was last seen. “I thought the probable end of her timeframe for survival was the end of the day on Sunday.”

When Luckin estimates someone’s chances are slim, he says to police: “I look forward to the phone call telling me I’m absolutely wrong, that you’ve found them alive and well.”

“I love being proved wrong in those circumstances. The more you tell me I’m wrong, the happier I am.”

Police will search past the deadline and renew a search if new information comes to light, Whitehead says. “It’s never determined by cost.” In his time, about 2 per cent of people were found dead and around 1 per cent were never found at all. “We have an obligation to find people. We generally go on for another two or three days to allow for us to find something, a deceased person, a bone, or actually find them if they survived.”

It can be difficult work for volunteers called in after the obvious places have been searched. “We don’t have a lot of happy endings,” says Ryan of searches she’s been on. Some moments she still treasures: the search for toddler Anthony Elfalak was on its fourth day in the Hunter Region of NSW in 2021 when the child was found by a helicopter, sitting in a creek bed less than half a kilometre from the family home. Ryan heard his mother’s voice as the police shared the news that he was safe. “It wasn’t a call, it wasn’t a yell, but something in between. That’s the sound I will never forget. That’s the one we rarely get.”

Luckin will never forget the 72-year-old prospector lost in the WA outback in 2023. He estimated the man could survive only a short time in the blistering heat. Then police found tracks with an even gait that told them the prospector was in better condition than assumed. “I extended the timeframe for survival by 24 hours,” Luckin says. The man was found severely dehydrated within half an hour of when Luckin thought he would die. “He survived to the absolute limit. He said afterwards, when he lay down where they found him, he knew he wouldn’t be getting up.”

“I realised why they couldn’t find me. It was just total cover. There’s nothing you could see down there.”

Madeleine had two sips of water left on Sunday morning when she emerged from the forest near some holidaymakers at a campsite on the coast at K’gari. “I thought, oh my god, I must look like some bedraggled dangerous creature – so I started by just saying, ‘Hello, I’m…’ And they looked at me and said, ‘We know who you are, thank goodness you’re here, what can we do?’” She asked for water, and they called triple zero.

Clive had just wished a group of SES volunteers good luck for the day when he got word Madeleine had been found. But it wasn’t until she got out of the police car that he felt a wave of relief and then joy.

“I was the first one to grab her,” he says. “I was checking her out; she looked a bit gaunt in the face and had a big, embarrassed smile. But she looked fine.“ Madeleine felt relief because Clive and her friends knew she was OK. “He didn’t let me out of his sight for the rest of the day.”

“The police said to me, ‘You know, it’s very rare that at this stage it’s a good ending. Three nights is a bit long.’”

As a helicopter whisked her to a hospital for tests, she looked down at the island. “I realised why they couldn’t find me. It was just total cover. There’s nothing you could see down there.”

She’s wiser now about what a wrong step can do. “That’s the whole of life, isn’t it,” she says. “If you make a mistake, it has lots of consequences. And you then have to deal with them.”

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