Most children get a thrill out of finding a fossil, but some never lose that sense of excitement. Nick Morrison meets a childhood collector who has grown up into a dinosaur hunter.

ABOUT five years ago, Will Watts was out for a walk on the North York Moors when something in a stream caught his eye. To most people, it would have been a fairly ordinary looking, yellowish rock, with a bumpy ridge running through the middle, but what Will saw was enough to send a shiver of anticipation down his spine.

For he recognised that bumpy ridge as the footprint of a small therapod, a carnivorous dinosaur from the middle Jurassic period, around 160 million years ago, and, with a footprint about nine inches long, measuring around four feet tall.

"I knew straight away because I knew what I was looking at, but if you had shown me ten years ago I would have thought it was a lump of rock," he says.

"There is something special about dinosaur footprints. I think it is more impressive than a bone, to think that bit of rock was actually stood on by a dinosaur. A bone is quite a sedentary object, but a dinosaur footprint is quite dynamic - the dinosaur stood there and then moved off again - and it is a fleeting glimpse into its life."

Like many of us, Will started looking for fossils on childhood expeditions with his parents, along the beach at his home town of Scarborough, and along the North Yorkshire coast, as well as on the moors. One birthday treat involved fossil collecting at Runswick Bay. And for Will it is a passion which has not gone away. After a degree in geology, and spells working at both the Yorkshire Museum, in York, and PC World, he finds himself, at 24, the Dinosaur Coast project officer.

Based in Scarborough, his remit covers the Yorkshire coast from Staithes in the north to Filey in the south, and inland to take in the entire North York Moors National Park. And a combination of circumstance and luck makes it one of the best places in the world to find evidence of the days when dinosaurs ruled the world.

"The area of the national park and the coastline is incredibly rich in Jurassic rocks, and Jurassic rocks are full of fossils. They can tell us a great deal about the past environments, but the really great thing about this area is that a lot of them are in quite accessible locations. You can go down on the beach and see footprints, you can walk down the slipway at Robin Hood's Bay and you are in the middle of a 180 million year old environment.

"There are certain spots - Robin Hood's Bay, Runswick Bay and Scarborough - where you can just get out of your car and walk down to the beach and it is all around you."

The northern section of the coast, around Whitby and Runswick Bay, is rich in lower Jurassic rocks, laid around 180 million years ago, and containing spiral ammonites, and fossils of sea creatures including ichthyosaurs and plesiosaurs.

Middle Jurassic rocks are widespread across the moors, where footprints of dinosaurs wandering across river deltas and swamps provide evidence of everything from the massive diplodocus, to stegosaur-type creatures, to therapods similar to allosaurus. And on the coast, middle Jurassic plant fossils are particularly significant.

"The fossil plants of the Yorkshire coast are internationally important - they are some of the best examples of that age of plant material. Middle Jurassic rocks are quite rare across the world, there are not that many places where they were well exposed, and we have probably one of the best sections of them in the world," Will says.

Further down the coast, around Scarborough, the limestone rocks are teeming with upper Jurassic fossils, from around 140 million years ago, containing ammonites and evidence of other sea creatures.

But rich though the dinosaur heritage is, it is largely luck which has made it of international significance, quite apart from the odds against a fossil being formed in the first place. Unless the creature's body has been buried in the right kind of rock, it will be crushed or otherwise destroyed, leaving no trace of its existence.

IF it has been fossilized, it has got to come to the surface and be exposed before it can be found. And it is here that the North Yorkshire coast and moors come into their own.

A strip of Jurassic rock runs from North Yorkshire to Dorset on the south coast, but it is only at its two extremities that it is exposed. Along the coast, the cause is erosion, which has seen the sea strip away layer after layer, bringing the Jurassic rock to the surface. On the moors, it is the movement of the hills themselves, as they are thrust upwards by geological forces, which has sent the surface layers sliding away to reveal the Jurassic rocks underneath.

The abundance of fossils meant the Yorkshire coast was one of the most prominent areas in the development of the science of geology in the 18th century, and is still a popular destination for students and experts in the field.

"Jurassic rocks are underneath all of us, it is just that they have got other rocks on top of them in other parts of the country," Will says. "Erosion has left us with a fantastic window. If the coast were not eroding, we would not be finding fossils on the beach."

As Dinosaur Coast project officer, a post set up by Scarborough Borough Council, Whitby Museum, the national park authority, English Nature and the Yorkshire Museums Council, and supported by the Heritage Lottery Fund, it is Will's job to promote awareness of the area's heritage, as well as encourage people to get actively involved.

From fossil hunts to boat trips, geological tours to a fossil version of the Antiques Roadshow, the project aims to nurture the same sort of enthusiasm which saw Will spend his childhood looking for evidence of the terrible lizards.

"My idea of an enjoyable Saturday is out on the beach seeing what I can find, and quite often a walk on the moors will just happen to go past a site where I might find something. It is my hobby, but I'm one of the lucky people who happens to be paid to do what I enjoy doing," he says.

"Show me a five or six-year-old who doesn't enjoy finding a fossil - I was just one of those people who carried on doing that. When you see something like a footprint, the chances are you are the first living creature to see that for more than 100 million years. That initial excitement of finding something lives with you. It still gives you a buzz - it doesn't matter how old you are."

*Information on Dinosaur Coast events is available from Will on (01723) 232572 or www.dinocoast.org.uk