Clutching an iPhone and dressed in a pressed tablecloth-checked shirt, shiny cufflinks and blue chinos, Ray Mears does not look like much of a survivalist. A leather knapsack at his feet is the only hint that the man folded into a plump leather armchair opposite is not an accountant, but even the contents of that disappoint.
Did he pack emergency supplies? A survival knife, or a flare perhaps? "No," he replies flatly, "You bring what's appropriate for the situation you're in. That wouldn't be appropriate." The 45-year-old bushcraftsman, whose earnest round face and softly spoken enthusiasm has captivated British television audiences for more than 16 years, doesn't do gimmickry. He also doesn't really seem to do humour.
Sitting in the upstairs lobby of Canada House off Trafalgar Square, he is almost deadpan as he describes his latest filming trip for the BBC series, Northern Wilderness. Rather than reeling off tales of sledging escapades, narrow escapes from bear attacks or camping in minus 30, he wants to discuss the ancient bushcraft skills of the Native Canadians, which he says are now at risk of being lost forever.
"In Canada we were looking for particular skills and there were some things we couldn't show because people just weren't there," he explains earnestly. "There were people with the knowledge who used to live on a trap-line, but they have followed their children into towns. Then their diet changes, they get overweight, they get back problems and their whole life changes."
The traditional skills of survival have been Mears's stock in trade ever since he founded the Woodlore School of Wilderness Bushcraft in 1983, so he feels keenly the loss of knowledge amongst communities such as the Native Canadians. "The loss of elders in first-nation communities across the world is happening at an exponential rate because of the detrimental effects of a changed diet, lifestyle and particularly diabetes and the health implications that that brings," he says, furrowing his brow. "So at a time when the world is crying out for traditional knowledge, the flame itself is fading fast."
Despite the sincerity of his passion for traditional skills, however, it is only when the conversation turns to the television shock tactics of his rival survivalists that he becomes truly animated. "I'm so anti all that stuff," he almost shouts. "I've spent my TV career trying to show people that wild places are not threatening if you have the right knowledge and the right attitudes, but there are people out there making programmes who want you to feel exactly the opposite when they have no experience of these places. That really winds me up."
Mears is a fairly old-fashioned phenomenon in television programming: an expert, rather than a good-looking stunt man; his understated explanation of bushcraft techniques presents an almost placid view of wild places. His belief in that style of programme-making got him into trouble last year when he dubbed rival TV survivor Bear Grylls a "boy scout", for his youth and excitable presenting style. But instead of backing away from the criticism, he extends it to all his television rivals. Does he admire any current presenters of survival or outdoor programming on television? "No," he replies.
"TV people are increasingly giving the wrong people the opportunity. When I started doing television, they were a lot more careful about who they put in front of the camera, but that's changed. There are people who try to copy what I do in terms of talking to the camera with expertise, and it is insulting to see someone stand up and think that they're experts after 10 minutes' knowledge. It's ridiculous. But that's the kind of world we live in where people think they're experts overnight. It doesn't work that way. You have to be an apprentice. I met an Inuit in Canada who had seen my programmes before and he said he liked them because I told it as it is. He lives it, so that's the highest praise I could get."
In many ways, Mears trod an unlikely path to outdoor guru. He grew up in the suburban streets of Kenley, Surrey – a place he cannily describes as the "North Downs" on his website. His parents were never that interested in the wilderness. His father, a printer for The Times, and mother were "supportive and encouraging" of their only child's desire to hang out in the woods, but he was never far from roads or people.
The first wild camping he remembers was very near civilisation, but far from enticing him back, that only seemed to enhance his sense that he was in the better place. "I remember sleeping out for the first time without a sleeping bag, in an orange survival bag. After about half an hour I realised that wouldn't work, so I lit a fire and stayed up all night, watching planes circle and cars in the distance. I was thinking about people inside watching the TV and all I could think was how much richer I was."
These experiences, he says, that have made him evangelical about the slices of British countryside left near towns. "We retain the wild areas of Britain very well in terms of national parks and countryside but what we're losing is the little wild spaces. There's increasing pressure on the oh-so-precious green belt and our greed is reflected in the amount of concrete we pour. Those little green spaces may not seem very wild, but they are wild: they contain species, animals, birds and plants that are immensely important to us as a nation. They also provide places for the spiritual well-being of our people. You only have to look at how popular parks are in London to see that there's a need for these spaces.
"The measure of a civilisation is how well we manage to live alongside the wild things around us. If we can succeed in finding a way to live in harmony with the wild things around us than we must be doing other things right in terms of pollution, environmental caretaking and so on."
While he is happy to express an opinion on everything from wild spaces to the Gurkhas (he's a big sympathiser) and global warming, the one subject Mears won't dwell on is his relationships. His wife Rachel died from breast cancer in 2006 and he is intensely sensitive about his private life. Even before the word "relationships" is out of my mouth, the shutters have come down. Does his solitary work ever make it difficult to sustain friendships? "No. I wouldn't let it. I would always put the friendship first," he says, in a tone that suggests that line of conversation is finished.
Fortunately, he claims loneliness is never a problem. "No, I don't get lonely. I am by nature quite solitary, and yet my work has brought me into contact with people almost continuously, so the thing I really enjoy is doing trips on my own. I love doing canoe trips alone particularly. I like my own company and I never feel alone because I'm surrounded by wildlife and there are lots of aspects of being alone that are healthy and to be encouraged."
Perhaps it was all the talk of being alone, or maybe it was discussing the outdoors from a darkened room on a sunny day, but at this point in the conversation his eyes have begun to glaze over. At the first suggestion of going outside, he is up and out of his seat.
Walking to St James's Park, people stop to gawp. "I don't believe in all this celebrity stuff," he says, turning his cufflinks and eyeing the crowd of people who have gathered to watch. "Is that an MP?" an elderly lady whispers to a friend, thrown by his City clobber. But as Mears climbs into a tree and leans back for a picture, the penny drops. "Oh, it's that bloke of the telly, you know, the one who lives in the woods," she squeaks. And it's easy to see how she worked it out: for the first time all day he looks at home.
A woodsman's tracks
Born 1964, Kenley, Surrey.
1969-75 Downside Lodge and Downside Prep School, Purley, Surrey. Begins sleeping outside and tracking foxes in the North Downs.
1975-82 Reigate Grammar School.
1982 Gets job in the City after failing to get into Royal Marines because of poor eyesight.
1983 Founds the Woodlore School in East Sussex.
1992 Meets future wife, Rachel, and publishes first book, The Outdoor Survival Handbook.
1994 First television presenting job for the BBC series Wild Tracks.
1997 Gets his own television show, Ray Mears' World of Survival.
1999 First series of Ray Mears' Extreme Survival on the BBC.
2002 Fourth book, Bushcraft, published, prompting two television series of the same name.
2003 Ray Mears' Real Heroes of Telemark, the story of a secret mission to stop Hitler's atomic bomb goes out on the BBC.
2005 Narrowly avoids death in a helicopter crash in the Rockies.
2006 Rachel dies from breast cancer.
2007 Ray Mears' Wild Food, demonstrating traditional cooking techniques, broadcast worldwide.
2008 Ray Mears Goes Walkabout, Australian survival series, broadcast.
2009 Northern Wilderness, a series on Canadian bushcraft techniques broadcast, and accompanying book published.
'Northern Wilderness' by Ray Mears is published by Hodder & Stoughton, (price £20). His BBC2 series starts next Sunday