‘We must cherish Planet Earth’

He joins Sir David Attenborough to launch the series on Sunday evening. Programmes to follow will feature a line-up of stars including Graham Norton, Will Young, Edith Bowman, Jack Osbourne and Carol Thatcher.

Over the next few weeks they will explore the work of global conservation charities before appealing to the public to make a donation to help save endangered wildlife.

Crocodiles, tigers, turtles, orang-utans and albatrosses are among the animals featured while, closer to home, special regional programmes focus on our own endangered wildlife including, in Yorkshire, the red kite, marsh harrier and great-crested newt.

Alan joins Sir David to present the celebrity expeditions, featuring nine UK-based charities raising cash for global issues. And during the fundraising finale, he makes an appeal for donations to help save the planet's wildlife.

The TV gardening guru, who was born and raised on the edge of Ilkley Moor, is thrilled to be co-hosting the series, highlighting an issue close to his heart.

"It is hugely important," he says. "We tend to concentrate so hard on the political issues and forget that the over-riding, most important thing, we should do is to cherish the landscape worldwide, and the creatures that live in it."

He believes the many celebrities taking part will do much to highlight the plight of the creatures under threat. "I think the involvement of them will get people watching who might not otherwise watch. People, for instance, who like Will Young may be interested to find out what he is doing."

In one programme, Will Young finds out about the problems faced by lowland gorillas who are hunted for bushmeat and whose habitat in Gabon, in west-central Africa, is being destroyed by logging.

Another episode sees Jack Osbourne finding out how Namibian elephants are in competition with man.

Edith Bowman highlights how Cambodian crocodiles are threatened by the leather trade and Graham Norton reveals why Ethiopian wolves are under threat from domestic dogs.

Locally, actor, author, adventurer and ecological campaigner Brian Blessed, who was born in South Yorkshire, visits Harewood House near Leeds to try to spot the magnificent red kite - a protected species. His other destinations include Filey Downs Nature Reserve, home to rare great-crested newts.

Alan stresses how important it is that we look after our own wild creatures. "Our main films are global, but we are also looking at local projects. It is as vital to care for local wildlife," he says.

He has had a lifelong interest in wildlife. "I joined Wharfedale Naturalists' Society when I was eight and have been a member for 50 years. I've always been interested in anything that crawled, swam or flew. Plants became my thing as they were right outside the back door."

The garden is often the place where a child first encounters wildlife too, he adds. "Gardens are a great interactive environment for naturalists." With his wife, Alan runs Gardens for Schools, which makes grants to primary schools for gardens and nature areas. "It is a small charity, and we now have 285 gardens," he says. "When children become interested in nature and see it for themselves, it blows them away, they are fascinated."

Alan, who lives in Hampshire, remembers how much he enjoyed wildlife and nature programmes on TV, while he was growing up. "I go back to the days of Peter Scott and Johnny Morris, whose programmes were always fascinating."

And, in the same way that people can do their bit to help stem global warming, the public can help save endangered wildlife. "It seems such an enormous subject but people can help and they will be given details showing them how.

"Making changes is a gradual thing - chipping away, a steady drip, drip, drip, in the same way as the move to reduce emissions."

Of age-old practices such as hunting rhino for their horn, Alan stresses that we have to appreciate the traditions of other cultures, which stretch back many centuries. "That is the way they always have been. These issues have to be approached sensitively. It is about finding the most effective way to conserve.

"I think we need not lose sight of the reason we are doing this, and that is for the beauty, the importance, the huge profound depth of nature which is so joyful."

He said efforts to care for the world around us can sometimes be seen as "finger-wagging," but, he adds, we need to think about where we live.

"We need to step back and see how beautiful, how wonderful Earth is, and remember that we have been given custody of it to hand on to future generations."

• Saving Planet Earth begins on Sunday at 7pm and is then screened every evening until Friday, July 6, with the celebrities looking at the plight of different species. It also features on CBBC, BBC2 and at bbc.co.uk/savingplanetearth where visitors can find out how they can join in the effort to help endangered animals from fundraising events to ways of donating.