When the world of nature first exploded on to our TV screens David Bellamy became our navigator, pushing back the layers of lush greenery in far-flung places and inviting us into his world.

The distinctive and endearing accent was the trademark that provided aspiring mimics with a wealth of routines. In documentaries and on children's television he gesticulated wildly, all facial hair and hands. But that was more than a decade ago, and David Bellamy is not stand-up material any more.

Little else has changed. As he sits across a table for lunch in Dublin this week, the hands and mouth are working overtime as he talks about his work and travels. For a man in his mid-60s he gets about a lot. "I was at home for only 19 days last year," he says between spoonfuls of seafood chowder. "I went around the world seven times. I lead a privileged life."

He is dressed just as you would expect for a world-famous botanist, eco-warrior, author and authority on all subjects green. Suede desert boots peep out from khaki slacks topped off by a T-shirt which bears the slogan of today's environmental cause, the Bord Gais Millennium Urban Forest Campaign. He is here to plant a tree for the project although "I should really hate trees, I'm a bog-man," he says.

His love of Irish boglands and the writings of the Irish botanist and naturalist Robert Lloyd Praeger have made him a hibernophile. The proposed Clifden Airport on rare bogland near Roundstone is of huge concern to him.

Bellamy first started campaigning 40 years ago in Sierra Leone. Much of his work now centres on the running of family planning clinics in 27 countries around the world. He also makes films, writes books and plants an awful lot of trees.

We spend more time destroying the Earth than saving it, he says. "People are more avaricious, expecting a higher standard of living."

It is tourism he believes that will ultimately save the world. "I'm working with Disney at the moment. While you don't often hear about it, his theme park is the best example of green tourism in the world: he has what amounts to a nature reserve there. Look at tourism in Ireland. You import money and you export goodwill," he says. "It is the best industry."

He once mentioned his belief to Margaret Thatcher, who swiftly retorted: "Tourism is not an industry. You don't make anything". He liked Thatcher. When he was released, along with hundreds of others, from a Tasmanian prison for successfully stopping a dam being built he was summoned to No 10.

"I thought I was in for a blasting," he remembers. "But she said "There are votes in this green business, aren't there?"

He has met Tony Blair and thinks he is "an idiot" who reacts according to whatever his spin-doctors say. Democracy doesn't work in Britain any more, he believes. "You have an arch-conservative party in at the moment that calls itself Labour. I think most young people have lost faith in government," he says.

"We have grown out of democracy," says the man who ran for the late James Goldsmith's Referendum Party in the last general election in Britain and polled just under 4,000 votes.

His life revolves around the environment and his company Botanic Enterprises Publications Ltd. He lives, when he is home, with his wife and grandson in the Pennines. He earns, he says, around £30,000 a year ("You don't need more than that") and has never owned a watch. Talk to him about life beyond the environment and he is suddenly quiet.

He has always loved ballet, but even the two ballets he wrote had environmental themes. "I like digging in the garden," he says, searching vainly for a hobby not connected with his life's work. "It's what I do," he says, giving up.

What he doesn't do any more is children's television. "They say I don't speak streetwise language. Maybe the broadcasting companies don't like what I say. I mean, who owns the media? Rupert Murdoch hates my guts because I closed his concrete factory down in Tasmania," he says.

Media conspiracies aside, he is content. He believes it is crucial to work alongside the traditional enemies of the green movement such as large oil and gas companies, to educate them on the need for green initiatives in industry.

Genetically modified products worry him, and visiting countries which oppress women, as he does quite often, is depressing. "Actually men are irrelevant in the scheme of things," he says. David Bellamy, bog-lover, tree-hugger and feminist, mops up the last of his garlic spaghetti and smiles: "The more you travel the more you realise how bloody ignorant you are."