Tom Hardy from the Cornwall Wildlife Trust explains how to spot a basking shark
Fancy coming face to face with a shark larger than the great white and whose mouth could swallow you whole?
That's exactly what conservationists in Cornwall are hoping - they're appealing for volunteers to spot basking sharks, which gather in their hundreds off the British coast.
But don't worry, you can spend from dawn to dusk from the safety of a cliff-top vantage point and, besides, the sharks they are after are completely harmless.
Basking sharks might be the biggest creature to be found anywhere in the UK, but they use their giant mouths to filter seawater for plankton, nothing larger.
When forced to the surface to feed, they have been mistaken for simply basking in the sunshine.
And when they do, each sighting will be logged by a band of volunteers at two sites in Cornwall as part of the first survey of its kind.
For Mike Langshaw, a member of the Cornwall Wildlife Trust and now a shark spotter, you shouldn't underestimate the nature of the job.
We're trying to find out what time of day they feed, how long they spend feeding and looking at other behaviour, like mating behaviour
Joana Doyle, Cornwall Wildlife Trust
"It's hard work to concentrate for this length of time. We're here for nearly 15 hours a day - but yes, it is very interesting."
Samantha Fraser agrees. A marine biology student, she too has given up weeks of her time to join Mr Langshaw at Carn Gloose, near St Just, in what is a beautiful location.
Hundreds of feet up on a cliff-top, they enjoy a breath-taking panoramic view of the Atlantic. But be warned - conditions are not always so pleasant.
"It depends on the weather. It's a beautiful location, and if you get to see some wildlife it's an added bonus, but it can get quite cold and windy".
They both know their efforts could prove an invaluable scientific resource. Precious little is known about the basking shark.
Basking sharks often gather off the south coast of the UK
Joana Doyle from the Cornwall Wildlife Trust is behind the project and hopes to build up a better picture of these enigmatic creatures.
"We know that basking sharks come here every summer to feed on plankton in the water," she said.
"We're trying to find out what time of day they feed, how long they spend feeding and looking at other behaviour, like mating behaviour."
She hopes to use the research to put pressure on government to protect the areas she's identified as being popular with these filter feeders.
It would be a move resisted by fisherman, who are already prohibited from fishing this threatened species.
Either way Ms Doyle knows there could be other benefits. "We get a lot of reports each year of other types of sharks like great whites.
"We're hoping as well that this might dispel the myths. Most of the time I've seen an image of an apparent great white - it's been a basking shark."
They may be cousins but the basking shark couldn't be more different from the feared great white.
Harmless and docile, the basking shark does nonetheless often get confused with the apex predator it is related to. Another benefit of this new research could be to highlight those differences.
Al Reeve from the Shark Trust hopes so.
He said: "From this survey we think more people will appreciate that we've got sharks on our coastline, that they are not dangerous killing machines and also enjoy the fact that we can share the waters with such great sized animals."
And at 10 metres long basking sharks are certainly large - but tell that to this team of volunteers.
Even on a fine day, when you're hundreds of feet from the water, looking out to sea, it's a difficult task to spot a dorsal fin or tail poke out of the waves.
The Cornwall Wildlife Trust hopes to publish its findings by Christmas - but first they have to find a few basking sharks.
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