Rare footage thought to be of the Westcountry's legendary sea monster Morgawr has rekindled one woman's memories of a sighting 20 years ago.

Carrie Ham, 92, has kept a scrapbook of newspaper cuttings about the Cornish sea serpent since 1976, when she first noticed sightings reported near her home on the Helford River at Falmouth.

She said yesterday that she doubted the creature really existed - until one day in the early 1980s when she spotted something strange in the river.

"I went down one morning and saw a black thing in the water and thought it was a yacht turned upside down," she said.

"Then it sunk and came up again and I thought, 'that's queer', so I got my binoculars and I looked again.

"Up came something like a big arm, shaking something at the end of it which I took to be a fish. It was a bit too far up the river to look closely and then it sank, and I didn't see it again."

Mrs Ham said she was extremely interested in footage captured by John Holmes at Gerrans Bay on the Roseland Peninsula which was featured in the Western Morning News yesterday.

Mr Holmes, a former Natural History Museum worker, filmed the creature three years ago and believes it could be a marine dinosaur called a plesiosaur, thought to have died out 64 million years ago.

But Mike Thomas, managing director of Newquay Zoo, said he had put overlays on to Mr Holmes' video footage and he believed it was probably a sunfish - not the Morgawr.

"There are lots of things in the water that have not been discovered, so I wouldn't discount the fact that there is something strange in the sea - in fact I support that," he said.

"But in this case the odds are that it was probably a sunfish. They are quite big - up to two or three metres - and they have got a dorsal fin that sticks out of the water quite a way. Many people have mistaken sunfish for something else."

Westcountry writer Sheila Bird saw what she believed to be the Morgawr on a clear, bright evening in July 1985, during a walk at Porthcurno, near Truro, with her brother.

She said she had seen Mr Holmes' video footage, but it was not similar to the creature they saw that day.

"All I can say is that it's very interesting but I can't identify it as the same thing we saw," she said.

She described a mottled grey creature, about 20ft long, with a tail about the same length.

"My first reaction was shock and the first thought that went into my head was that it had escaped from the pages of a story book," she said.

"We were on cliffs looking towards Gerrans Bay. The sun was shining directly on to it and it was only about 100 yards away away. It was a most beautiful, magnificent creature, holding its head up like a camel.

"It didn't have the appearance of an aggressive monster.

"I consulted various experts, including palaeontologists, who knew instantly what I was talking about. They said that what I had seen was a descendant of plesiosaurs thought to be extinct for over 64 million years."

The last reported sighting of the Morgawr was in May, when the cox for the St Piran patrol boat and a fisherman, both from Falmouth, spotted the creature on the same day.

Cox Dan Matthew, an experienced sailor, could not believe what he had seen until a week later when he heard that fisherman George Vinnicombe had also seen the creature that day. Mr Vinnicombe also reported seeing the Morgawr in the 1970s.