TO LIVE up to his public image of a rugged, ex-SAS adventurer, it must have seemed essential for Bear Grylls to appear at ease sleeping rough and catching his own food in his television survival series.

But it has emerged that Grylls, 33, was enjoying a far more conventional form of comfort, retreating some nights from filming in mountains and on desert islands to nearby lodges and hotels.

Now Channel 4 has launched an investigation into whether Grylls, who has conquered Everest and the Arctic, deceived the public in his series Born Survivor.

The series, screened in March and April and watched by 1.4m viewers, built up Grylls’s credentials as a tough outdoorsman. In a question and answer session on Channel 4’s website, he recalls how station bosses pitched the venture to him stating: “We just drop you into a lot of different hellholes equipped with nothing, and you do what you have to do to survive.”

But an adviser to Born Survivor has disclosed that at one location where the adventurer claimed to be a “real life Robin-son Crusoe” trapped on “a desert island”, he was actually on an outlying part of the Hawaiian archipelago and spent nights at a motel.

On another occasion in California’s Sierra Nevada mountains where he was filmed biting off the head of a snake for breakfast and struggling for survival “with just a water bottle, a cup and a flint for making fire”, he actually slept some nights with the crew in a lodge fitted with television and internet access. The Pines Resort at Bass Lake is advertised as “a cosy getaway for families” with blueberry pancakes for breakfast.

In one episode Grylls, son of the late Tory MP Sir Michael Grylls, was shown apparently building a Polynesian-style raft using only materials around him, including bamboo, hibiscus twine and palm leaves for a sail.

But according to Mark Weinert, an Oregon-based survival consultant brought in for the job, it was he who led the team that built the raft. It was then dismantled so that Grylls could be shown building it on camera.

In another episode viewers watched as Grylls tried to coax an apparently wild mustang into a lasso in the Sierra Nevada. “I’m in luck,” he told viewers, apparently coming across four wild horses grazing in a meadow. “A chance to use an old native American mode of transport comes my way. This is one of the few places in the whole of the US where horses still roam wild.”

In fact, Weinert said, the horses were not wild but were brought in by trailer from a nearby trekking station for the “choreographed” feature.

“If you really believe everything happens the way it is shown on TV, you are being a little bit naive,” he said.

Channel 4 confirmed that Grylls had used hotels during expeditions and has now asked Diverse, the Bristol-based production company that made the programme, to look into the other claims.

“We take any allegations of misleading our audiences seriously,” said a spokeswoman for the channel.

The latest suggestion that Channel 4 may have breached viewer trust comes as the broad-caster’s supervisory board prepares to issue new editorial guidelines to suppliers in order to stamp out alleged sharp practices that mislead viewers.

“Born Survivor is not an observational documentary series but a ‘how to’ guide to basic survival techniques in extreme environments,” the spokeswoman said.

“The programme explicitly does not claim that presenter Bear Grylls’s experience is one of unaided solo survival.”

Nevertheless, the disclosure is likely to disappoint fans of the Eton-educated adventurer, who at the age of 23 became the youngest Briton to scale Everest. Just two years before that he had broken his back in three places after his parachute ripped during a military exercise.

On screen he has emerged as a natural performer, with stunts such as squeezing water from animal dung and sucking the fluid from fish eyeballs.

Grylls could not be contacted for comment this weekend as he was trekking in the Brecon Beacons with his four-year-old son.

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