BBC (London, UK) 12 May 08 Slippery treasure of the undergrowth (Sarah Mukherjee)
The Herpetological Conservation Trust is urging members of the public to take part in a project that will identify and enumerate one of Britain's most exotic native wildlife species - the adder.
The "Add an Adder" interactive map will allow people to record their sightings online - which will be used to help conservationists decide on their strategy to protect these increasingly rare creatures.
I have been out spotting the adders with one of the trust's members, Nick Milton.
"Look over there! Yes, just there! Can you see it?"
I was beginning to wonder whether anybody is likely to see an adder at all to record on the interactive map
"Oh, yes" I say, uncertainly. I point my binoculars to a piece of scrubby ground. I see - a piece of scrubby ground.
"See, it's moving!"
No, I don't see, actually. I don't see anything other than the bits of old log and brambles that are carefully managed to ensure the tiny community of adders - one of only two left in London - stay viable.
I was beginning to wonder whether anybody is likely to see an adder at all to record on the interactive map.
They certainly don't go out of their way to be noticed.
I thought that those zigzag stripes would make them stick out like a Christmas tree. But it seems that it really is the best way to stay hidden.
It takes a good half hour of stopping and looking before I finally begin to see what Nick has seen from the start - snakes.
Basking, curling up, slithering through the undergrowth.
And then, after a few grass snake false starts - the real thing.
A beautiful, female adder, basking on a log, flattened out so she could get the greatest benefit from the sun.
And yes, those zigzag stripes do allow her to blend seamlessly into the grass that is, by now, dappled with sunlight.
For nature lovers, it's one of the best sights Britain has to offer.
For everyone else, it's an unwelcome encounter with one of our country's few poisonous animals.
"There are only 10 adults here, and only recently I found that one had been killed by someone.
"They are not aggressive animals," says Nick. "Of course if they're molested, or poked, or sat on, they'll react. But wouldn't you?"
But surely it's understandable - it is, after all, a poisonous animal.
"Snakes are, statistically speaking, far less dangerous than stinging insects like wasps or bees. And while they are still widespread, their habitat is beginning to disappear. We need as many sightings as possible on the map so we can work out how to conserve the habitats we have."
Nick has been very lucky. He has seen, this year, male adders wrestling with each other for supremacy - known traditionally as "the dance of the adders" - a very rare sight.
"Around here, the adders could move up to a mile as they move from their hibernation sites."
Says Nick: "So the males have been encountering one another - and I have been lucky enough to see it."
It's not yet 9am, and already the sun is high and hot.
The female adder shows herself one more time, and silently slips away.
Conservationists hope that the species will not end up doing the same.
Slippery treasure of the undergrowth