Last Chance to See hits our screens this week starting in the Amazon. I was a little apprehensive about this first shoot to be honest. Travelling with Stephen was going to be like travelling with Wikipedia. I remember sending a video blog about this at the time. He's far too unassuming and generous to make anyone feel in any way deficient on purpose, but there's no escaping the fact that he's the kind of person who makes you continually question your own intellect.
It didn't even cross my mind at the time, but he was a little apprehensive too. We did have at least one thing in common. Our Amazon adventure had been occupying our thoughts a great deal over the previous year or so, and we were both thrilled and eager to get started.
We went to the Amazon to look for the Amazonian manatee.
Despite weeks of trying, Douglas and I had failed to see one on our original expedition twenty years ago. Actually, that's not strictly true. Our jungle guide saw a manatee disappear beneath the surface of a remote tributary of the Rio Negro. I saw the ripples after it had disappeared and Douglas nearly saw the ripples. (You can listen to the 1989 radio programme for more on this!) Stephen and I were determined to do better. But we failed too. We were all outfoxed by one of the slowest creatures on Earth.
Perhaps it wasn't surprising. No one knows how many Amazonian manatees are left, but here's a hint at their current status: in the 1980s, there were reports of as many as 1,000 manatees huddled together in a single river or lake; nowadays, a gathering of half a dozen is considered a lot.
But we did see a lot of other wildlife along the way, of course, and one of the highlights for me was a day we spent swimming with pink river dolphins. These are the kind of animals young children paint at school. A particularly naïve teacher might relegate the exuberant splashes of dazzling pink, the chubby cheeks, the long beak crammed with crushing teeth and the gargantuan designer flippers to a wild and fertile young imagination. But pink river dolphins are real - and they really are as pink as an embarrassed teenager's blush.
I also discovered the science of dendronautics - the navigation and study of the jungle canopy. If you fancy a career change, with more day-to-day risks than coal mining, deep-sea diving or flying with the Red Arrows, this is the job for you. And it's perfect for dinner party conversation because, joy of joys, you would be allowed to call yourself a dendronaut!
But I think what stands out most in my mind from this trip is the Amazon rainforest itself. It's hard to grasp the sheer scale and splendour of the largest non-stop expanse of pure, unremitting nature on earth. Larger than the whole of western Europe and heaving with wildlife, it is utterly mind-boggling.
It's also disappearing fast. You couldn't dream up a bigger list of more damaging activities if you tried: cattle ranching, land clearance for soya-bean plantations, small-scale subsistence agriculture, logging, and a mixed bag of commercial agriculture, mining, urbanisation and dam construction... just for starters.
What's really frightening is that nothing much seems to have changed since deforestation first hit the headlines several decades ago. Have all those years of campaigning, fund-raising, pleading, cajoling and cautioning by so many individuals and conservation groups made the slightest difference? I suppose the positive response would be to say that it must, surely, have slowed things down. But clearly it hasn't slowed things down anywhere near enough.
I hope you enjoy the first programme in the series. It starts on Sunday 6 September, 8pm on BBC Two.