YouTube survival show contestant goes missing in forest sparking huge manhunt

A contestant taking part in a YouTube survival show has been rescued 18 hours after she got lost in a forest.

The 36-year-old woman, whose identity has not yet been released, left base camp at around 5pm on Friday in search of water - but she never returned, prompting the contest's hosts to launch a desperate search.

After their efforts failed, police were called in at 5am on Saturday and they launched a coordinated sniffer dog and helicopter search in the densely wooded area.

Around 10:40 am, troopers located the missing woman deep within a swampy region. Photos released by authorities showed the survivalist waving frantically to helicopters overhead.

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The woman, from California, went missing in the Pigeon River Forest in northern Michigan. An ice storm earlier in the year had left many fallen tree trunks and branches in the already-dense woods, which hampered search efforts.

Police confirmed that law enforcement officers and firefighters were able to walk her out of the cold, damp woods safely. She was evaluated by emergency medical services and released with no serious injuries, according to UpNorthLive.

It comes after a man was forced to "slurp unclean pond water" to stay alive for nine days after his car broke down in a vast wilderness.

Andrew Barber had written the word 'help' into a massive rock and spelled out 'SOS' in mud in a desperate bid to be rescued in the Cariboo region of British Columbia, Canada.

The 39-year-old, who went missing on July 31, survived by drinking pond water and he built a shelter made from wood and mud. He was eventually found on August 8 by the Royal Canadian Mounted Police after a helicopter saw his broken down vehicle which allowed them to hone in on the area.

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Rescuers said that he had used survival tactics to stay alive but was severely dehydrated and he had an injury to his leg.

"I don't know that he would have made it another 24 hours without us recovering him," said Bob Zimmerman, from Quesnel Search and Rescue. "He was in poor health, he was having a hard time standing."

An image from the rescue team shows a type of bivouac that Andrew had built from wood and mud, which was next to a rock that had the word 'help' written on it.

Mr Barber went missing near McLeese Lake which is around 365 miles north of Vancouver after his vehicle broke down.

"He was literally slurping unclean pond water to stay hydrated," Staff Sgt. Brad McKinnon of the Williams Lake Royal Canadian Mounted Police McKinnon, told Canadian Press News. "The human body can go a long time without food, but water is a different situation.

"I'll put it this way — had we not found him when we did, I would have had graver concerns than I currently do. We had been at this for nine days, and it was essentially like looking for a needle in a haystack. The Cariboo region of British Columbia is beautiful, but it is immense, and there are tons of rural and wilderness areas."

After being found, Andrew was flown to Cariboo Memorial Hospital in Williams Lake for treatment. He has now been discharged and is doing "quite well" considering his ordeal.