Nessie mania returned to Scotland yesterday after new pictures were printed of Scotland’s most reclusive resident.

The new photos appeared to show a slimmer Loch Ness monster, prompting fervent speculation that the living dinosaur could have been pregnant.

Instead of the usual fleeting glimpse afforded her followers, Nessie stayed above the surface long enough for retired printer Roy Johnston to take at least four photographs showing the suspiciously snake-like Nessie arching out of the water and returning to it with a splash. The new photographs, printed in yesterday’s Daily Mail, prompted an immediate debate as to whether they are genuine.

Johnston, 63, said he and his wife, Janet, had been nearing the end of a Highlands driving holiday two weeks ago when he decided to stop in a lay-by near the loch.

He made his way to the loch’s edge at around 9am and had been standing there only a few minutes before the "creature" emerged.

"I thought I was going mad," he said. "The first thought that sprang into my mind was, ‘That’s an elephant.’ I know it sounds silly but it looked like a trunk. It was the same length and width.

"I wondered if the creature was a conger eel, but it was way too big for that. It was about seven or eight feet out of the water and it was obvious that there was more of it underneath the surface."

The sighting has delighted tourism businesses in the area. Malaina Krott-Thiarry, a worker at a tourist information centre close to the loch, said: "I have no idea what to make of these pictures, but I think they’re good news for the area. This might lead to a boost for business later this year or next year."

Lawrence Sear, the managing editor of the Daily Mail, said there was absolutely no sign the photographs had been doctored.

"We collected the negatives from Mr Johnston and they were absolutely genuine. They have not been manipulated at any stage," he said.

"Who knows whether the images are of the Loch Ness monster or not? All we can say is that those pictures are genuine and have not been doctored."

But Scotland on Sunday’s picture editor, Kayt Turner, said there was room for doubt.

The Daily Mail published a sequence of pictures to represent the object emerging from the water and then submerging.

But the third picture in the sequence, representing the splash of water, was appreciably lighter in colour than the previous two images.

Turner said: "Those pictures were not taken in sequence."

A picture editor for 15 years, she added: "Anyone with a spare £500 can get the equipment needed to digitally manipulate this kind of image, using a simple software package such as Photoshop. All you need is a scanner and a computer.

"Looking at this image it is impossible to tell if there has been any manipulation. It would be very simple to take a picture of an object and place it in the loch.

"The only way you could be sure they are genuine would be to see the original negatives."

The pictures have started a squabble between the Daily Mail and the News of the World. The latter is expected to pour cold water over the sighting, as it has signed up a Nessie expert to analyse the pictures.

The expert, Adrian Shine, who has spent 20 years in a scientific quest for Nessie, was barred from talking to Scotland on Sunday but a friend said: "We’re all very sceptical."